+----------+-----------------------------------------------------------+
| ### N    |                                                           |
| ISN Acro |                                                           |
| nym List |                                                           |
+----------+-----------------------------------------------------------+
|          |                                                           |
+----------+-----------------------------------------------------------+
| A&WS     | Application and Web Services                              |
+----------+-----------------------------------------------------------+
| A/D      | Analog to Digital                                         |
+----------+-----------------------------------------------------------+
| A/G      | Air-to-Ground                                             |
+----------+-----------------------------------------------------------+
| A/V      | Audio/Video                                               |
+----------+-----------------------------------------------------------+
| AA       | Associate Administrator                                   |
+----------+-----------------------------------------------------------+
| AAA      | Authentication, Authorization and Accounting              |
+----------+-----------------------------------------------------------+
| AADS     | Ameritech Advanced Data Services                          |
|          |                                                           |
|          | Ascent Air Data System                                    |
+----------+-----------------------------------------------------------+
| AAP      | Affirmative Action Plan                                   |
+----------+-----------------------------------------------------------+
| AARNET   | Australian Academic & Research Network                    |
+----------+-----------------------------------------------------------+
| AAS      | Agencywide Administrative Systems                         |
|          |                                                           |
|          | Adapters for Application Servers                          |
+----------+-----------------------------------------------------------+
| AASE     | Airborne Arctic Stratospheric Expedition                  |
+----------+-----------------------------------------------------------+
| AASO     | Agency Accounting Systems Office                          |
+----------+-----------------------------------------------------------+
| AATT     | Advanced Aircraft Transportations Technologies            |
+----------+-----------------------------------------------------------+
| ABC      | Advanced Business Communications Corporation              |
+----------+-----------------------------------------------------------+
| Abend    | Abnormal end                                              |
+----------+-----------------------------------------------------------+
| ABR      | Available Bit Rate                                        |
+----------+-----------------------------------------------------------+
| ABS      | Automated Billing System                                  |
+----------+-----------------------------------------------------------+
| AC       | Alternating Current                                       |
+----------+-----------------------------------------------------------+
| ACA      | Associate Contractor Agreement                            |
+----------+-----------------------------------------------------------+
| ACB      | Access Control Block                                      |
+----------+-----------------------------------------------------------+
| ACC      | Analog Conversion Card                                    |
+----------+-----------------------------------------------------------+
| ACD      | Architectural Control Document                            |
|          |                                                           |
|          | Active Circuits Directory                                 |
+----------+-----------------------------------------------------------+
| ACE      | Advanced Composition Explorer                             |
|          |                                                           |
|          | Application Characterization Environment                  |
+----------+-----------------------------------------------------------+
| ACF      | Access Control Facility                                   |
+----------+-----------------------------------------------------------+
| ACI      | Administratively Controlled Information                   |
+----------+-----------------------------------------------------------+
| Ack      | Acknowledgement                                           |
+----------+-----------------------------------------------------------+
| ACL      | # Access Control List                                     |
+----------+-----------------------------------------------------------+
| ACP      | Activity Contention Period                                |
+----------+-----------------------------------------------------------+
| ACR      | Administrator's Conference Room                           |
+----------+-----------------------------------------------------------+
| ACRIMSAT | Active Cavity Radiometer Irradiance Satellite             |
+----------+-----------------------------------------------------------+
| ACRV     | Assured Crew Return Vehicle                               |
+----------+-----------------------------------------------------------+
| ACS      | Advanced Communications Services                          |
+----------+-----------------------------------------------------------+
| ACTS     | Advanced Communications Technology Satellite              |
+----------+-----------------------------------------------------------+
| ACWP     | Actual Cost of Work Performed                             |
+----------+-----------------------------------------------------------+
| AD       | Active Directory                                          |
+----------+-----------------------------------------------------------+
| AD&I     | Avionics Design and Integration                           |
+----------+-----------------------------------------------------------+
| ADEOS    | Advanced Earth Observing System                           |
+----------+-----------------------------------------------------------+
| ADP      | Automated Data Processing                                 |
+----------+-----------------------------------------------------------+
| ADPE     | Automatic Data Processing Equipment                       |
+----------+-----------------------------------------------------------+
| ADSR     | Agencywide Information Management (AIM) Document          |
|          | Specifications Requirements                               |
+----------+-----------------------------------------------------------+
| ADU      | Asynchronous Data Unit                                    |
+----------+-----------------------------------------------------------+
| AEE      | Advanced Engineering Environment                          |
+----------+-----------------------------------------------------------+
| AES      | Advanced Encryption Standard                              |
|          |                                                           |
|          | Advanced Encryption System                                |
+----------+-----------------------------------------------------------+
| AFB      | Air Force Base                                            |
+----------+-----------------------------------------------------------+
| AFRTS    | Armed Forces Radio and Television Service                 |
+----------+-----------------------------------------------------------+
| AFSCN    | Air Force Satellite Control Network                       |
+----------+-----------------------------------------------------------+
| AGC      | Automatic Gain Control                                    |
+----------+-----------------------------------------------------------+
| AGMEMS   | AT&T Government Markets Enterprise Management System      |
+----------+-----------------------------------------------------------+
| AGO      | Santiago, Chile, Tracking Station                         |
+----------+-----------------------------------------------------------+
| AGS      | Alaska Ground Station                                     |
|          |                                                           |
|          | Americom Government Services                              |
|          |                                                           |
|          | Poker Flat Research Range                                 |
+----------+-----------------------------------------------------------+
| AIP      | Automated Interface Processors                            |
+----------+-----------------------------------------------------------+
| AIS      | Automated information Security                            |
+----------+-----------------------------------------------------------+
| AIU      | Antenna Interface Unit                                    |
+----------+-----------------------------------------------------------+
| AIX      | Advanced Interactive Executive                            |
+----------+-----------------------------------------------------------+
| ALC      | Agency Location Code                                      |
+----------+-----------------------------------------------------------+
| AMMOS    | Advanced Multi-mission Operations Systems                 |
+----------+-----------------------------------------------------------+
| AMOS     | Automated Mission Operations System                       |
+----------+-----------------------------------------------------------+
| AMX      | AMX is the name of a company now known as Panja           |
+----------+-----------------------------------------------------------+
| ANC      | Active Nutation Control                                   |
+----------+-----------------------------------------------------------+
| ANCC     | Auxiliary Network Control Center                          |
+----------+-----------------------------------------------------------+
| ANI      | Automated Numbering System                                |
+----------+-----------------------------------------------------------+
| ANIWG    | Aqua Network Implementation Working Group                 |
+----------+-----------------------------------------------------------+
| ANSER    | Analytical Services                                       |
+----------+-----------------------------------------------------------+
| ANTL     | NREN Laboratory at ARC                                    |
+----------+-----------------------------------------------------------+
| ANVIL    | Army-NASA Virtual Innovations Laboratory                  |
+----------+-----------------------------------------------------------+
| AoE      | Area of Emphasis                                          |
+----------+-----------------------------------------------------------+
| AOPNS    | Activity and Outage Posting and Notification System       |
+----------+-----------------------------------------------------------+
| AP       | Array Processor                                           |
|          |                                                           |
|          | Audio Perfect                                             |
+----------+-----------------------------------------------------------+
| APAN     | Asian Pacific Area Network                                |
+----------+-----------------------------------------------------------+
| APC      | Vendor - American Power Conversion                        |
|          |                                                           |
|          | Hardware - Advanced processed control                     |
+----------+-----------------------------------------------------------+
| APGN     | Alaska Polar Ground Network                               |
+----------+-----------------------------------------------------------+
| API      | Applications Programming Interface                        |
+----------+-----------------------------------------------------------+
| APL      | Applied Physics Laboratory                                |
+----------+-----------------------------------------------------------+
| APM      | Associate Program Manager                                 |
+----------+-----------------------------------------------------------+
| AQF      | Astronaut Quarantine Facility                             |
+----------+-----------------------------------------------------------+
| Aqua     | Name of Project                                           |
+----------+-----------------------------------------------------------+
| AR       | Anomaly Report                                            |
|          |                                                           |
|          | Annual Review                                             |
+----------+-----------------------------------------------------------+
| ARC      | Ames Research Center                                      |
+----------+-----------------------------------------------------------+
| ARIN     | American Registry for Internet Numbers                    |
+----------+-----------------------------------------------------------+
| ARSW     | Action Request System Web                                 |
+----------+-----------------------------------------------------------+
| ARTCC    | Air Route Traffic Control Center                          |
+----------+-----------------------------------------------------------+
| AS&T     | Atlantic Science and Technology                           |
+----------+-----------------------------------------------------------+
| ASAP     | As Soon As Possible                                       |
+----------+-----------------------------------------------------------+
| ASCC     | Academia Sinica Computing Centre                          |
+----------+-----------------------------------------------------------+
| ASCII    | American Standard Code Information Interchange            |
+----------+-----------------------------------------------------------+
| ASF      | Alaska Satellite Facility                                 |
+----------+-----------------------------------------------------------+
| ASI      | Italian Space Agency/Agency Space Italiana                |
|          |                                                           |
|          | Arion Systems, Inc.                                       |
|          |                                                           |
|          | Asynchronous Serial Interface                             |
+----------+-----------------------------------------------------------+
| ASMS     | Antenna Simulator and Modeling System                     |
+----------+-----------------------------------------------------------+
| ASN      | Access Stack Node                                         |
|          |                                                           |
|          | Autonomous System Number                                  |
+----------+-----------------------------------------------------------+
| ASP      | Attached Satellite Payload                                |
+----------+-----------------------------------------------------------+
| ASR      | Agency Service Request                                    |
+----------+-----------------------------------------------------------+
| ASRI     | Allied Signal Research, Inc. (Company name)               |
+----------+-----------------------------------------------------------+
| ASRS     | Automated Support Requirement System                      |
+----------+-----------------------------------------------------------+
| ASTER    | Advance Spaceborne Thermal Emission and Reflection        |
+----------+-----------------------------------------------------------+
| ASU      | Arizona State University                                  |
+----------+-----------------------------------------------------------+
| AT       | Acceptance Test                                           |
|          |                                                           |
|          | Architecture Team                                         |
+----------+-----------------------------------------------------------+
| AT&T     | American Telephone and Telegraph                          |
+----------+-----------------------------------------------------------+
| ATC      | Lockheed-Martin Advanced Technology Center                |
+----------+-----------------------------------------------------------+
| ATK      | Alliant Techsystems                                       |
+----------+-----------------------------------------------------------+
| ATM      | Asynchronous Transmission Mode                            |
|          |                                                           |
|          | Asynchronous Transfer Mode                                |
+----------+-----------------------------------------------------------+
| ATP      | Authorization to Proceed                                  |
|          |                                                           |
|          | Authorization to Process                                  |
|          |                                                           |
|          | Acceptance Test Plan                                      |
+----------+-----------------------------------------------------------+
| ATV      | All-Terrain Vehicle                                       |
+----------+-----------------------------------------------------------+
| AUI      | Attachment Unit Interface                                 |
+----------+-----------------------------------------------------------+
| Aura     | Name of Mission                                           |
+----------+-----------------------------------------------------------+
| AV       | Anti-Virus                                                |
+----------+-----------------------------------------------------------+
| AWAS     | Airfield Wind Advisory System                             |
+----------+-----------------------------------------------------------+
| AWINS    | Agency Widows Internet Naming Services                    |
+----------+-----------------------------------------------------------+
| AXAF     | Advanced X-Ray Astrophysics Facility                      |
+----------+-----------------------------------------------------------+
| BAFM     | Business and Financial Management                         |
+----------+-----------------------------------------------------------+
| BAFO     | Best and Final Offer                                      |
+----------+-----------------------------------------------------------+
| BAH      | Booz, Allen and Hamilton                                  |
+----------+-----------------------------------------------------------+
| BASP     | Ball AeroSpace                                            |
+----------+-----------------------------------------------------------+
| BB       | Bit Block                                                 |
+----------+-----------------------------------------------------------+
| BBC      | British Broadcasting Corporation                          |
+----------+-----------------------------------------------------------+
| BCCP     | Business Continuity and Contingency Plan                  |
+----------+-----------------------------------------------------------+
| BCR      | Budget Cost Request                                       |
+----------+-----------------------------------------------------------+
| BCWP     | Budgeted Cost of Work Performed                           |
+----------+-----------------------------------------------------------+
| BCWS     | Budget Cost of Work Scheduled                             |
+----------+-----------------------------------------------------------+
| BDA      | Bermuda                                                   |
+----------+-----------------------------------------------------------+
| BERK     | University of California, Berkeley                        |
+----------+-----------------------------------------------------------+
| BERT     | Bit Error Rate Test                                       |
+----------+-----------------------------------------------------------+
| BET      | Best Estimate Trajectory                                  |
+----------+-----------------------------------------------------------+
| BGP      | Border Gateway Protocol                                   |
+----------+-----------------------------------------------------------+
| BIND     | Berkeley Internet Name Daemon                             |
+----------+-----------------------------------------------------------+
| BIOS     | Basic Input/Output System                                 |
+----------+-----------------------------------------------------------+
| BLDR     | University of Colorado at Boulder                         |
+----------+-----------------------------------------------------------+
| BLOS     | Bigelow Laboratory for Ocean Sciences                     |
+----------+-----------------------------------------------------------+
| BMC      | Name of company that provides Remedy Software             |
+----------+-----------------------------------------------------------+
| BMCC     | Boeing Mission Control Center, El Segundo, CA             |
+----------+-----------------------------------------------------------+
| BNC      | Bayonet Neill-Concelman (a connector)                     |
+----------+-----------------------------------------------------------+
| BOAC     | Billing Office Account Code                               |
+----------+-----------------------------------------------------------+
| BOE      | Basis of Estimate                                         |
+----------+-----------------------------------------------------------+
| BOM      | Bill of Materials                                         |
+----------+-----------------------------------------------------------+
| BOP      | Big Optical Pipe or preferably -- Mission Support         |
|          | Backbone Upgrade                                          |
+----------+-----------------------------------------------------------+
| bps      | Bits per second                                           |
+----------+-----------------------------------------------------------+
| BPX      | Broadband Packet Exchange                                 |
+----------+-----------------------------------------------------------+
| BRI      | Basic Rate Interface                                      |
+----------+-----------------------------------------------------------+
| BRT      | Business and Restricted Technology                        |
+----------+-----------------------------------------------------------+
| BSOD     | Blue Screen of Death                                      |
+----------+-----------------------------------------------------------+
| BSS      | Best Source Select                                        |
+----------+-----------------------------------------------------------+
| BWG      | Beam Wave Guide                                           |
+----------+-----------------------------------------------------------+
| BXM      | Broadband Switch Module                                   |
+----------+-----------------------------------------------------------+
| C&A      | Certification and Accreditation                           |
+----------+-----------------------------------------------------------+
| C/A      | Computer Associates                                       |
+----------+-----------------------------------------------------------+
| C/NOFS   | Communications/Navigation Outage Forecasting System       |
+----------+-----------------------------------------------------------+
| C/O      | Checkout                                                  |
+----------+-----------------------------------------------------------+
| CACS     | Computer Access Control System                            |
+----------+-----------------------------------------------------------+
| CADU     | Channel Access Data Units                                 |
+----------+-----------------------------------------------------------+
| CAE      | CSOC-Houston Architecture Engineering                     |
+----------+-----------------------------------------------------------+
| CAIB     | Columbia Accident Investigation Board                     |
+----------+-----------------------------------------------------------+
| CAITS    | Centerwide Action Item Tracking System                    |
+----------+-----------------------------------------------------------+
| CALIPSO  | Cloud-Aerosol Lidar and Infrared Pathfinder Satellite     |
|          | Observation                                               |
+----------+-----------------------------------------------------------+
| CAM      | Cost Account Manager                                      |
+----------+-----------------------------------------------------------+
| CAMB     | Cambridge, MA                                             |
+----------+-----------------------------------------------------------+
| CANDOS   | Communications and Navigation Demonstration On Shuttle    |
+----------+-----------------------------------------------------------+
| CANET\*4 | Canadian Research Network - Autonomous System Number      |
|          | (ASN) 4                                                   |
+----------+-----------------------------------------------------------+
| CAP      | Command and Attitude Processor                            |
|          |                                                           |
|          | Cost Action Plan                                          |
|          |                                                           |
|          | Corrective Action Plan                                    |
|          |                                                           |
|          | Cost Account Plan                                         |
+----------+-----------------------------------------------------------+
| CAR      | Corrective Action Request                                 |
|          |                                                           |
|          | Corrective Action Report                                  |
|          |                                                           |
|          | Corrective Action Response                                |
+----------+-----------------------------------------------------------+
| CARR     | Center for Applied Radiation Research                     |
+----------+-----------------------------------------------------------+
| CASI     | Center for Aerospace Information                          |
+----------+-----------------------------------------------------------+
| CAT      | Category                                                  |
+----------+-----------------------------------------------------------+
| CB       | Channel Bank                                              |
+----------+-----------------------------------------------------------+
| CBACS    | Common Badging Access Control System                      |
+----------+-----------------------------------------------------------+
| CBR      | Constant Bit Rate                                         |
+----------+-----------------------------------------------------------+
| CCAFS    | Cape Canaveral Air Force Station (old name)               |
+----------+-----------------------------------------------------------+
| CCAIMS   | Computing and Communications Assets Information           |
|          | Management System                                         |
+----------+-----------------------------------------------------------+
| CCAS     | Cape Canaveral Air Station (new name)                     |
+----------+-----------------------------------------------------------+
| CCB      | Configuration Control Board                               |
+----------+-----------------------------------------------------------+
| CCCMs    | Center Customer Commitment Managers                       |
+----------+-----------------------------------------------------------+
| CCNA     | Cisco Certified Network Associate                         |
+----------+-----------------------------------------------------------+
| CCO      | Contract Change Order                                     |
+----------+-----------------------------------------------------------+
| CCP      | Change Control Panel                                      |
+----------+-----------------------------------------------------------+
| CCS      | Communications and Control Segment                        |
+----------+-----------------------------------------------------------+
| CCSDS    | Consultative Committee for Space Data Systems             |
+----------+-----------------------------------------------------------+
| CCSR     | Communication and Control Segment Replacement             |
+----------+-----------------------------------------------------------+
| CCT      | Computer Compatible Tape                                  |
+----------+-----------------------------------------------------------+
| CD       | Compact Disk                                              |
|          |                                                           |
|          | Conversion Devise                                         |
+----------+-----------------------------------------------------------+
| CD&SC    | Communications Distribution and Switching Center          |
+----------+-----------------------------------------------------------+
| CDA      | Command and Data Acquisition                              |
+----------+-----------------------------------------------------------+
| CDC      | Command Data Center                                       |
+----------+-----------------------------------------------------------+
| CDD      | Custom Design Document                                    |
+----------+-----------------------------------------------------------+
| CDD      | Customer Design Document                                  |
+----------+-----------------------------------------------------------+
| CDE      | Consolidated Development Environment                      |
+----------+-----------------------------------------------------------+
| CDHF     | Central Data Handling Facility                            |
+----------+-----------------------------------------------------------+
| CDM      | Common Data Model                                         |
+----------+-----------------------------------------------------------+
| CDMGR    | Conversion Device Manager                                 |
+----------+-----------------------------------------------------------+
| CDMGT    | Conversion Device Management                              |
+----------+-----------------------------------------------------------+
| CDR      | Critical Design Review                                    |
+----------+-----------------------------------------------------------+
| CD-ROM   | Compact Disk-Read Only Memory                             |
+----------+-----------------------------------------------------------+
| CDSCC    | Canberra Deep Space Communication Complex                 |
+----------+-----------------------------------------------------------+
| CDT      | Central Daylight Time                                     |
+----------+-----------------------------------------------------------+
| CDTI     | Comsat Digital Teleport Incorporated                      |
+----------+-----------------------------------------------------------+
| CEC      | Collaborative Engineering Center                          |
+----------+-----------------------------------------------------------+
| CEDE     | Communications Engineering Development Environment        |
+----------+-----------------------------------------------------------+
| CEE      | Collaboration Engineering Environment                     |
+----------+-----------------------------------------------------------+
| CEF      | Cisco Express Forwarding                                  |
+----------+-----------------------------------------------------------+
| CERN     | Conseil Européen pour la Recherche Nucléaire\" (CERN)-    |
|          | European Organization for Nuclear Research                |
+----------+-----------------------------------------------------------+
| CERS     | Contractor Equipment Relocation System                    |
+----------+-----------------------------------------------------------+
| CERT     | Computer Emergency Response Team                          |
+----------+-----------------------------------------------------------+
| CES      | Circuit Emulation Service                                 |
+----------+-----------------------------------------------------------+
| CEWP     | Cost Estimate Work Package                                |
+----------+-----------------------------------------------------------+
| CFO      | Chief Financial Officer                                   |
+----------+-----------------------------------------------------------+
| CGRO     | Compton Gamma Ray Observatory                             |
+----------+-----------------------------------------------------------+
| CHIPSAT  | Cosmic Hot Interstellar Plasma Spectrometer               |
+----------+-----------------------------------------------------------+
| CIC      | CSOC Integration Center                                   |
|          |                                                           |
|          | Cisco Information Center                                  |
+----------+-----------------------------------------------------------+
| CICS     | Customer Information Control System                       |
+----------+-----------------------------------------------------------+
| CIDR     | Classless Inter-Domain Routing                            |
+----------+-----------------------------------------------------------+
| CIEF     | Carrier Independent Exchange Facility                     |
+----------+-----------------------------------------------------------+
| CIG      | Customer Interface Group                                  |
+----------+-----------------------------------------------------------+
| CIMS     | Cyber Identity Management System (DCNSS)                  |
+----------+-----------------------------------------------------------+
| CIO      | Chief Information Officer                                 |
+----------+-----------------------------------------------------------+
| CIOC     | CSOC Integrated Operations Center                         |
+----------+-----------------------------------------------------------+
| CISCO    | (Company name -- does not stand for anything)             |
+----------+-----------------------------------------------------------+
| CITE     | Cargo Integration Test Equipment                          |
+----------+-----------------------------------------------------------+
| CLCS     | Consolidated Launch Control System                        |
+----------+-----------------------------------------------------------+
| CLF      | Consolidated Logistic Facility                            |
|          |                                                           |
|          | Customer Logistics Facility                               |
+----------+-----------------------------------------------------------+
| CLI      | Calling Location Identifier                               |
+----------+-----------------------------------------------------------+
| CM       | Configuration Management                                  |
+----------+-----------------------------------------------------------+
| CMD/TLM  | Command Telemetry                                         |
+----------+-----------------------------------------------------------+
| CMM      | Contract Mission Manager                                  |
+----------+-----------------------------------------------------------+
| CMSM     | Center Mission Service Manager                            |
+----------+-----------------------------------------------------------+
| CNE      | Center Network Environment                                |
+----------+-----------------------------------------------------------+
| CNES     | Centre National d'Etudes Spartiales/French National       |
|          | Center for Space Studies                                  |
+----------+-----------------------------------------------------------+
| CNMOS    | Consolidated Network and Mission Operations Support       |
+----------+-----------------------------------------------------------+
| # CNOFS  | Communication/Navigation and Outage Forecasting System    |
+----------+-----------------------------------------------------------+
| # CNT    | Computer Network Technology                               |
|          |                                                           |
|          | Channel Extension                                         |
+----------+-----------------------------------------------------------+
| # COB    | Close of Business                                         |
+----------+-----------------------------------------------------------+
| # COD    | Center Operations Directorate                             |
+----------+-----------------------------------------------------------+
| CODEC    | Coder - Decoder                                           |
+----------+-----------------------------------------------------------+
| Code 290 | Information Services Division                             |
+----------+-----------------------------------------------------------+
| Code 291 | NASA Communications Branch                                |
+----------+-----------------------------------------------------------+
| Code 297 | Enterprise Information Technology Security Branch (EITSB) |
+----------+-----------------------------------------------------------+
| Code 450 | Space Communications Program                              |
+----------+-----------------------------------------------------------+
| Code M   | Office of Space Flight                                    |
+----------+-----------------------------------------------------------+
| Code S   | Office of Space Science                                   |
+----------+-----------------------------------------------------------+
| Code T   | Office of Exploration Systems                             |
+----------+-----------------------------------------------------------+
| Code Y   | Office of Earth Science                                   |
+----------+-----------------------------------------------------------+
| Codec    | Coder/Decoder                                             |
+----------+-----------------------------------------------------------+
| COFR     | Certification of Flight Readiness                         |
+----------+-----------------------------------------------------------+
| COG      | Chandra Operational Gateway                               |
+----------+-----------------------------------------------------------+
| COL      | Contracting Officer Letter                                |
+----------+-----------------------------------------------------------+
| COLA     | Center for Ocean-Land-Atmosphere Studies                  |
+----------+-----------------------------------------------------------+
| COM      | Continuous Operations Messaging                           |
+----------+-----------------------------------------------------------+
| COMMGR   | Communications Manager                                    |
+----------+-----------------------------------------------------------+
| COMNET   | Communications Network                                    |
+----------+-----------------------------------------------------------+
| COMSEC   | Communications Security                                   |
+----------+-----------------------------------------------------------+
| CONUS    | Continental United States                                 |
+----------+-----------------------------------------------------------+
| COOP     | Continuity Of Operations Plan                             |
+----------+-----------------------------------------------------------+
| COPS     | Computer Operations                                       |
+----------+-----------------------------------------------------------+
| COR      | Central Office of Records                                 |
+----------+-----------------------------------------------------------+
| CoS      | Class of Service                                          |
+----------+-----------------------------------------------------------+
| COTR     | Contracting Officers Technical Representative             |
+----------+-----------------------------------------------------------+
| COTS     | Commercial-Off-The-Shelf                                  |
+----------+-----------------------------------------------------------+
| CPE      | Customer Provided Equipment                               |
|          |                                                           |
|          | Change Package Engineer                                   |
|          |                                                           |
|          | Chief Program Engineer                                    |
+----------+-----------------------------------------------------------+
| CPI      | Computational Physics Incorporated                        |
+----------+-----------------------------------------------------------+
| CPU      | Central Processing Unit                                   |
+----------+-----------------------------------------------------------+
| CR       | Change Request                                            |
+----------+-----------------------------------------------------------+
| CRC      | ## Cyclic Redundancy Check                                |
+----------+-----------------------------------------------------------+
| CRF      | ## Communications Resource Facility                       |
+----------+-----------------------------------------------------------+
| CRL      | Certificate Revocation List                               |
+----------+-----------------------------------------------------------+
| CS       | ## Cisco Secure                                           |
+----------+-----------------------------------------------------------+
| CSA      | Canadian Space Agency                                     |
+----------+-----------------------------------------------------------+
| C-SAFS   | Central Standard Autonomous File Server                   |
+----------+-----------------------------------------------------------+
| CSART    | CSOC Security Analysis and Response Team                  |
+----------+-----------------------------------------------------------+
| CSC      | Computer Sciences Corporation                             |
+----------+-----------------------------------------------------------+
| CSD      | Crew Systems Division                                     |
+----------+-----------------------------------------------------------+
| CSLA     | Contract Service Level Agreement                          |
+----------+-----------------------------------------------------------+
| CSM      | Customer Satisfaction Metrics                             |
+----------+-----------------------------------------------------------+
| CSO      | Computer Services Organization                            |
|          |                                                           |
|          | Computer Security Official                                |
+----------+-----------------------------------------------------------+
| CSOC     | Consolidated Space Operations Contract                    |
+----------+-----------------------------------------------------------+
| CSP      | Cost Savings Profile                                      |
+----------+-----------------------------------------------------------+
| CSR      | Customer Service Representative                           |
|          |                                                           |
|          | Customer Service Request                                  |
|          |                                                           |
|          | Communications Service Request                            |
+----------+-----------------------------------------------------------+
| CST      | Central Standard Time                                     |
+----------+-----------------------------------------------------------+
| CSU      | Channel Service Unit                                      |
|          |                                                           |
|          | Computer Software Unit                                    |
+----------+-----------------------------------------------------------+
| CSU/DSU  | Channel Service Unit/Digital Service Unit                 |
+----------+-----------------------------------------------------------+
| CTI      | Command Technology Inc.                                   |
+----------+-----------------------------------------------------------+
| CTO      | Chief Technical Officer                                   |
+----------+-----------------------------------------------------------+
| CTRM     | CSOC Technical Reporting and Metrics                      |
+----------+-----------------------------------------------------------+
| CTS      | Call to Station                                           |
+----------+-----------------------------------------------------------+
| CU       | Colorado University in Boulder, Colorado                  |
| -Boulder |                                                           |
+----------+-----------------------------------------------------------+
| CV       | Cost Variance                                             |
+----------+-----------------------------------------------------------+
| CVPN     | Corporate Virtual Private Network                         |
+----------+-----------------------------------------------------------+
| CVU      | Command Verification Unit                                 |
+----------+-----------------------------------------------------------+
| CWBS     | Contract Work Breakdown Structure                         |
+----------+-----------------------------------------------------------+
| CWDM     | Coarse Wavelength Division Multiplexer                    |
+----------+-----------------------------------------------------------+
| CWM      | Cisco WAN Manager                                         |
+----------+-----------------------------------------------------------+
| D/A      | Directory Assistance                                      |
+----------+-----------------------------------------------------------+
| DAAC     | Distributive Active Archive Center                        |
+----------+-----------------------------------------------------------+
| DACS     | Directory Access Control System                           |
+----------+-----------------------------------------------------------+
| DARPA    | Defense Advanced Research Projects Agency                 |
+----------+-----------------------------------------------------------+
| DART     | Disaster Assessment Recovery Team                         |
+----------+-----------------------------------------------------------+
| DAS      | Demand Access System                                      |
+----------+-----------------------------------------------------------+
| DAT      | Disaster Assessment Team                                  |
+----------+-----------------------------------------------------------+
| DAV      | Desktop Appliance Video Teleconferencing System (ViTS)    |
+----------+-----------------------------------------------------------+
| DB       | NASA/JSC Organization                                     |
|          |                                                           |
|          | Database                                                  |
+----------+-----------------------------------------------------------+
| dB       | decibel                                                   |
+----------+-----------------------------------------------------------+
| DBA      | Data Base Administrator                                   |
+----------+-----------------------------------------------------------+
| dBm      | Decibel (refers to 1 Milliwatt)                           |
+----------+-----------------------------------------------------------+
| DBR      | Data Base Record                                          |
+----------+-----------------------------------------------------------+
| DC       | Direct Current                                            |
|          |                                                           |
|          | District of Columbia                                      |
+----------+-----------------------------------------------------------+
| DCF      | Data Capture Facility                                     |
+----------+-----------------------------------------------------------+
| ## DCMA  | Defense Contract Management Agency                        |
+----------+-----------------------------------------------------------+
| DCN      | Document Change Notice                                    |
+----------+-----------------------------------------------------------+
| DCNSS    | Data Center Network and Security Services                 |
+----------+-----------------------------------------------------------+
| DCOM     | Distributed Component Object Model                        |
+----------+-----------------------------------------------------------+
| DCR      | Data Change Request                                       |
+----------+-----------------------------------------------------------+
| DCS      | Design Cost Schedule                                      |
+----------+-----------------------------------------------------------+
| DDCS     | Document and Data Control System                          |
+----------+-----------------------------------------------------------+
| DDDS     | Data Distribution Data Services                           |
+----------+-----------------------------------------------------------+
| DDOS     | Distributed Denial of Service                             |
+----------+-----------------------------------------------------------+
| DDS      | Data Distribution System                                  |
+----------+-----------------------------------------------------------+
| DECNET   | Digital Equipment Corporation Network                     |
+----------+-----------------------------------------------------------+
| DFI      | Developmental Flight Instrumentation                      |
+----------+-----------------------------------------------------------+
| DFRC     | Dryden Flight Research Center                             |
+----------+-----------------------------------------------------------+
| DHCP     | Dynamic Host Configuration Protocol                       |
+----------+-----------------------------------------------------------+
| DiD/DoD  | Direct In-Dial/Direct Out-Dial                            |
+----------+-----------------------------------------------------------+
| DIMM     | Dual In-line Memory Module                                |
+----------+-----------------------------------------------------------+
| DISA     | Defense Information Systems Agency                        |
+----------+-----------------------------------------------------------+
| DI       | ??-United National Relief and Rehabilitation              |
| SO-UNRRA | Administration                                            |
+----------+-----------------------------------------------------------+
| DITSM    | Deputy Information Technology Security Manager            |
+----------+-----------------------------------------------------------+
| DLL      | Data Link Libraries (DLLs)                                |
+----------+-----------------------------------------------------------+
| DLN      | Distance Learning Network                                 |
+----------+-----------------------------------------------------------+
| DLT      | Digital Linear Tape                                       |
+----------+-----------------------------------------------------------+
| DLT/DAT  | Tape Formats                                              |
+----------+-----------------------------------------------------------+
| DMI      | Desktop Management Interface                              |
+----------+-----------------------------------------------------------+
| DMR      | Detailed Mission Requirement                              |
|          |                                                           |
|          | Data Move Request                                         |
+----------+-----------------------------------------------------------+
| DMS      | Digital Matrix Switch                                     |
+----------+-----------------------------------------------------------+
| DMZ      | Demilitarized Zone                                        |
+----------+-----------------------------------------------------------+
| DNS      | Domain Name Server                                        |
+----------+-----------------------------------------------------------+
| DNV      | Det Norske Veritas                                        |
+----------+-----------------------------------------------------------+
| DoC      | Department of Commerce                                    |
+----------+-----------------------------------------------------------+
| DoD      | Department of Defense                                     |
+----------+-----------------------------------------------------------+
| DOM      | Date of Memorandum                                        |
+----------+-----------------------------------------------------------+
| DOMSAT   | Domestic Satellite                                        |
+----------+-----------------------------------------------------------+
| DOS      | Disk Operating Systems                                    |
+----------+-----------------------------------------------------------+
| DPI      | Data Processing Installation                              |
+----------+-----------------------------------------------------------+
| DR       | Discrepancy Report                                        |
|          |                                                           |
|          | Drafting Request                                          |
+----------+-----------------------------------------------------------+
| DRAM     | Dynamic Random Access Memory                              |
+----------+-----------------------------------------------------------+
| DRC      | Data Reduction Center                                     |
+----------+-----------------------------------------------------------+
| DRD      | Data Requirement Document                                 |
|          |                                                           |
|          | Data Requirement Description                              |
+----------+-----------------------------------------------------------+
| DREN     | Department of Research and Education Network              |
+----------+-----------------------------------------------------------+
| DRS      | Discrepancy Reporting System                              |
+----------+-----------------------------------------------------------+
| DRT      | Disaster Recovery Team                                    |
+----------+-----------------------------------------------------------+
| DRTC     | Disaster Recovery Team Coordinator                        |
+----------+-----------------------------------------------------------+
| DRTS     | Decommission Readiness Test Set                           |
+----------+-----------------------------------------------------------+
| DS       | Digital Signal                                            |
+----------+-----------------------------------------------------------+
| DSL      | Digital Subscriber Line                                   |
+----------+-----------------------------------------------------------+
| DSM      | Data Service Manager                                      |
+----------+-----------------------------------------------------------+
| ## DSMC  | Data Services Management Center                           |
+----------+-----------------------------------------------------------+
| DSN      | Deep Space Network                                        |
+----------+-----------------------------------------------------------+
| DSNet    | Distributed Simulation Network                            |
+----------+-----------------------------------------------------------+
| DSNCC    | Deep Space Network Communications Complex                 |
+----------+-----------------------------------------------------------+
| DSN-IP   | Deep Space Network International Partner                  |
+----------+-----------------------------------------------------------+
| DSOC     | Deep Space Operation Center                               |
+----------+-----------------------------------------------------------+
| DSS      | Deep Space System                                         |
|          |                                                           |
|          | Deep Space Station                                        |
|          |                                                           |
|          | Decision Support System                                   |
|          |                                                           |
|          | Documentation Support Services                            |
+----------+-----------------------------------------------------------+
| DSU      | Data Services Unit                                        |
+----------+-----------------------------------------------------------+
| DSX      | Digital Services Cross Connect                            |
+----------+-----------------------------------------------------------+
| DTIC     | Defense Technical Information Center                      |
+----------+-----------------------------------------------------------+
| DTS      | Distributed Teleconferencing System                       |
+----------+-----------------------------------------------------------+
| DTV      | Digital Television                                        |
+----------+-----------------------------------------------------------+
| DVA      | Desktop ViTS Appliance                                    |
+----------+-----------------------------------------------------------+
| DVCS     | Data/Voice Communications System                          |
+----------+-----------------------------------------------------------+
| DVD      | Digital Video Disk                                        |
+----------+-----------------------------------------------------------+
| DVIS     | Digital Voice Intercommunication System                   |
+----------+-----------------------------------------------------------+
| E&M      | Ear and Mouth Signaling                                   |
+----------+-----------------------------------------------------------+
| EA       | Enterprise Architecture                                   |
+----------+-----------------------------------------------------------+
| EAC      | Emergency Action Console                                  |
|          |                                                           |
|          | Estimate at Completion                                    |
+----------+-----------------------------------------------------------+
| EAFB     | Edwards Air Force Base                                    |
+----------+-----------------------------------------------------------+
| EBNet    | EOSDIS Backbone Network                                   |
+----------+-----------------------------------------------------------+
| EC       | Engineering Change                                        |
+----------+-----------------------------------------------------------+
| ECANS    | Exploration Communications and Navigation System          |
+----------+-----------------------------------------------------------+
| ECC      | Emergency Control Center                                  |
|          |                                                           |
|          | Error Correcting Code (has to do with memory)             |
+----------+-----------------------------------------------------------+
| ECD      | Estimated Completion Date                                 |
+----------+-----------------------------------------------------------+
| ECITS    | Executive Council Information Technology Security         |
+----------+-----------------------------------------------------------+
| ECL      | Emitter Coupled Logic                                     |
+----------+-----------------------------------------------------------+
| ECOMM    | Emergency Communications                                  |
+----------+-----------------------------------------------------------+
| ECP      | Engineering Change Proposal                               |
|          |                                                           |
|          | Emergency Command Post                                    |
+----------+-----------------------------------------------------------+
| ECR      | Engineering Change Request                                |
+----------+-----------------------------------------------------------+
| ECS      | Environmental Control System                              |
+----------+-----------------------------------------------------------+
| EDC      | EOS Data Center                                           |
|          |                                                           |
|          | Engineering Design Change                                 |
+----------+-----------------------------------------------------------+
| EDOS     | EOS Data and Operations System                            |
+----------+-----------------------------------------------------------+
| EGD      | Entropy Gathering Daemon                                  |
+----------+-----------------------------------------------------------+
| EGP      | Exterior Gateway Protocol                                 |
+----------+-----------------------------------------------------------+
| # EH     | Environmental Health                                      |
+----------+-----------------------------------------------------------+
| # EHRS   | Electronic Health Records System                          |
+----------+-----------------------------------------------------------+
| # EHS    | Enhanced Huntsville Operations Support Center (**HOSC**)  |
|          | System (**EHS**)                                          |
+----------+-----------------------------------------------------------+
| # EIA    | Electronic Industries Alliance                            |
+----------+-----------------------------------------------------------+
| # EIGRP  | Enhanced Interior Gateway Routing Protocol                |
+----------+-----------------------------------------------------------+
| EIP      | Engineering Implementation Package                        |
|          |                                                           |
|          | Ethernet Interface Processor                              |
+----------+-----------------------------------------------------------+
| EIRR     | External Independent Readiness Review                     |
+----------+-----------------------------------------------------------+
| EIS      | Enterprise Information System                             |
|          |                                                           |
|          | External Interface System                                 |
+----------+-----------------------------------------------------------+
| EISD     | Estimated In-Service Date                                 |
+----------+-----------------------------------------------------------+
| EITSB    | Enterprise Information Technology Security Branch         |
+----------+-----------------------------------------------------------+
| ELI      | Electric Lightwave Network                                |
+----------+-----------------------------------------------------------+
| ELV      | Expendable Launch Vehicles                                |
+----------+-----------------------------------------------------------+
| EMAN     | Ecological Monitoring and Assessment Network (Canadian)   |
+----------+-----------------------------------------------------------+
| EMC      | Emergency Management Center                               |
+----------+-----------------------------------------------------------+
| EMC^2^,  | Company name                                              |
| Inc.     |                                                           |
+----------+-----------------------------------------------------------+
| EMON     | Enterprise Monitoring                                     |
+----------+-----------------------------------------------------------+
| EMS      | Electronic Maintenance Section                            |
+----------+-----------------------------------------------------------+
| EMSnet   | Emergency Management System                               |
+----------+-----------------------------------------------------------+
| ENMC     | Enterprise Network Management Center                      |
+----------+-----------------------------------------------------------+
| ENMS     | Enterprise Network Management System                      |
+----------+-----------------------------------------------------------+
| ENPL     | Earth Observatory System (EOS) Laboratory                 |
+----------+-----------------------------------------------------------+
| ENVISAT  | Environmental satellite                                   |
+----------+-----------------------------------------------------------+
| EO       | Engineering Order                                         |
+----------+-----------------------------------------------------------+
| EOC      | Emergency Operations Center                               |
+----------+-----------------------------------------------------------+
| EOL      | End of Life                                               |
+----------+-----------------------------------------------------------+
| EOM      | End of Mission                                            |
+----------+-----------------------------------------------------------+
| EOS      | Earth Observing System                                    |
+----------+-----------------------------------------------------------+
| EOSDIS   | EOS Data Information System                               |
+----------+-----------------------------------------------------------+
| EP       | Estimated Personnel                                       |
+----------+-----------------------------------------------------------+
| EPA      | Environmental Protection Agency                           |
+----------+-----------------------------------------------------------+
| EPGN     | EOS Polar Ground Network                                  |
+----------+-----------------------------------------------------------+
| EPGS     | EOS Polar Ground Station                                  |
+----------+-----------------------------------------------------------+
| EPIC     | EHS PDSS Integrated Changeout                             |
+----------+-----------------------------------------------------------+
| EPO      | Emergency Power OFF                                       |
+----------+-----------------------------------------------------------+
| EPOCC    | Enhanced Photo Optic Control Center (for GCAI)            |
+----------+-----------------------------------------------------------+
| ePORT    | Electronic Project Online Reporting Tool                  |
+----------+-----------------------------------------------------------+
| ERB      | EIP Review Board                                          |
+----------+-----------------------------------------------------------+
| ERBE     | Earth Radiation Budget Experiment                         |
+----------+-----------------------------------------------------------+
| ERBS     | Earth Radiation Budget Satellite                          |
+----------+-----------------------------------------------------------+
| ERDT     |                                                           |
+----------+-----------------------------------------------------------+
| EROS     | Earth Resources Observation Systems                       |
+----------+-----------------------------------------------------------+
| EROSEDC  | Earth Resources Observation Systems (EROS) Data Center    |
+----------+-----------------------------------------------------------+
| ERPS     | EOS Real Time Processing System                           |
+----------+-----------------------------------------------------------+
| ERS      | European Space Agency Remote Satellite                    |
+----------+-----------------------------------------------------------+
| ERSDAC   | Earth Remote Sensing Data Analysis Center                 |
+----------+-----------------------------------------------------------+
| ESA      | European Space Agency                                     |
+----------+-----------------------------------------------------------+
| ESB      | Earth-Swing-By                                            |
+----------+-----------------------------------------------------------+
| ESDIS    | Earth Science Data and Information System                 |
+----------+-----------------------------------------------------------+
| ESMD     | Exploration Systems Missions Directorate                  |
+----------+-----------------------------------------------------------+
| ESNet    | Energy Sciences Network                                   |
+----------+-----------------------------------------------------------+
| ESOC     | European Space Operations Center                          |
+----------+-----------------------------------------------------------+
| ESSP     | Earth System Science Pathfinder                           |
+----------+-----------------------------------------------------------+
| ESTEC    | ESA Science and Technology Center                         |
+----------+-----------------------------------------------------------+
| ESTL     | Electronic System Test Laboratory                         |
+----------+-----------------------------------------------------------+
| ET       | External Tank                                             |
+----------+-----------------------------------------------------------+
| ET TV    | External Tank Television                                  |
+----------+-----------------------------------------------------------+
| ETC      | Estimate to Complete                                      |
+----------+-----------------------------------------------------------+
| ETE      | End-To-End                                                |
+----------+-----------------------------------------------------------+
| ETH      | Ethernet                                                  |
+----------+-----------------------------------------------------------+
| ETM      | Engineering Test Motor                                    |
+----------+-----------------------------------------------------------+
| ETO      | Earth-to-Orbit                                            |
+----------+-----------------------------------------------------------+
| ETS      | EOSDIS Test System                                        |
+----------+-----------------------------------------------------------+
| ETTV     | External Tank Television                                  |
+----------+-----------------------------------------------------------+
| EUVE     | Extreme Ultraviolet Explorer                              |
+----------+-----------------------------------------------------------+
| EV       | Earned Value                                              |
+----------+-----------------------------------------------------------+
| EVA      | Extra Vehicular Activity                                  |
+----------+-----------------------------------------------------------+
| EvoDS    | Enhanced Voice Distribution System                        |
+----------+-----------------------------------------------------------+
| F/S      | Full Service                                              |
+----------+-----------------------------------------------------------+
| FAA      | Federal Aviation Administration                           |
+----------+-----------------------------------------------------------+
| FAQ      | Frequently Asked Questions                                |
+----------+-----------------------------------------------------------+
| FAR      | Federal Acquisition Regulation                            |
+----------+-----------------------------------------------------------+
| FAST     | Fast Auroral Snapshot Explorer                            |
+----------+-----------------------------------------------------------+
| FAST IP  | Fast Internet Protocol                                    |
+----------+-----------------------------------------------------------+
| FastE    | Fast Ethernet                                             |
+----------+-----------------------------------------------------------+
| FAT      | File Allocation Tables                                    |
+----------+-----------------------------------------------------------+
| FAX      | facsimile                                                 |
+----------+-----------------------------------------------------------+
| FBI      | Federal Bureau of Investigation                           |
+----------+-----------------------------------------------------------+
| FCC      | Federal Communications Commission                         |
+----------+-----------------------------------------------------------+
| FCDAS    | Fairbanks Command and Data Acquisition Station            |
+----------+-----------------------------------------------------------+
| FD       | Flight Dynamics                                           |
|          |                                                           |
|          | Flight Demonstration                                      |
+----------+-----------------------------------------------------------+
| FDDI     | Fiber Distributed Data Interface                          |
+----------+-----------------------------------------------------------+
| FDF      | Flight Data File                                          |
|          |                                                           |
|          | Flight Dynamics Facility                                  |
+----------+-----------------------------------------------------------+
| FDO      | Flight Dynamics Officer                                   |
+----------+-----------------------------------------------------------+
| FDSDIC   | Flight Dynamics Systems Development and Integration       |
|          | Center                                                    |
+----------+-----------------------------------------------------------+
| FDX      | Full Duplex                                               |
+----------+-----------------------------------------------------------+
| FEA      | Federal Enterprise Architecture                           |
+----------+-----------------------------------------------------------+
| FECC     | Far End Camera Control                                    |
+----------+-----------------------------------------------------------+
| FEL      | First Element Load                                        |
+----------+-----------------------------------------------------------+
| FEMA     | Federal Emergency Management Agency                       |
+----------+-----------------------------------------------------------+
| FEP      | Front-End Processor                                       |
+----------+-----------------------------------------------------------+
| FIPS     | Federal Information Processing Standard                   |
+----------+-----------------------------------------------------------+
| FIRST    | For Inspiration and Recognition of Science and Technology |
+----------+-----------------------------------------------------------+
| FISMA    | Federal Information Security Management Act               |
+----------+-----------------------------------------------------------+
| FIT      | Florida Institute of Technology                           |
+----------+-----------------------------------------------------------+
| FIX      | Federal Internet Exchange                                 |
+----------+-----------------------------------------------------------+
| FM       | Frequency Modulation                                      |
+----------+-----------------------------------------------------------+
| FN       | First Name                                                |
+----------+-----------------------------------------------------------+
| FOC      | Firm Order Commitment                                     |
+----------+-----------------------------------------------------------+
| FOIG     | Flight Operations Integrity Group                         |
+----------+-----------------------------------------------------------+
| FOM      | Facility Operations Manager                               |
+----------+-----------------------------------------------------------+
| FOT      | Flight Operations Team                                    |
+----------+-----------------------------------------------------------+
| FPD      | Flight Projects Department                                |
+----------+-----------------------------------------------------------+
| FRD      | Flight Requirements Document                              |
+----------+-----------------------------------------------------------+
| Freestar | Fast Reaction Experiments Enabling Science Technology     |
|          | Applications and Research                                 |
+----------+-----------------------------------------------------------+
| FRR      | Flight Readiness Review                                   |
+----------+-----------------------------------------------------------+
| FRS      | Federal Relay Service                                     |
+----------+-----------------------------------------------------------+
| FRT      | Flight Readiness Test                                     |
+----------+-----------------------------------------------------------+
| FSA      | Factory Service Agreement                                 |
+----------+-----------------------------------------------------------+
| FSAM     | Final Service Advisory Message                            |
+----------+-----------------------------------------------------------+
| FSCK     | Unix command to repair damaged files                      |
+----------+-----------------------------------------------------------+
| FSM      | Facility Systems Manager                                  |
|          |                                                           |
|          | Full Scale Motor                                          |
|          |                                                           |
|          | Flight Support Motor                                      |
+----------+-----------------------------------------------------------+
| FSSU     | Fault Sensing and Switching Unit                          |
+----------+-----------------------------------------------------------+
| FTE      | Full Time Equivalent                                      |
+----------+-----------------------------------------------------------+
| FTP      | Front-end Telemetry Processor                             |
|          |                                                           |
|          | File Transfer Protocol                                    |
+----------+-----------------------------------------------------------+
| # FTS    | Federal Telecommunications Services                       |
|          |                                                           |
|          | Federal Technology Service                                |
+----------+-----------------------------------------------------------+
| FUSE     | Far Ultraviolet Spectroscopic Explorer                    |
+----------+-----------------------------------------------------------+
| # FUSF   | Federal Universal Service Fund                            |
+----------+-----------------------------------------------------------+
| FV       | First Virtual Corporation                                 |
+----------+-----------------------------------------------------------+
| FW       | Firewall                                                  |
+----------+-----------------------------------------------------------+
| FX       | Model Name (not an acronym)                               |
+----------+-----------------------------------------------------------+
| FY       | Fiscal Year                                               |
+----------+-----------------------------------------------------------+
| GAS      | Gateway Assignment Sheet                                  |
+----------+-----------------------------------------------------------+
| GB       | Gigabyte                                                  |
+----------+-----------------------------------------------------------+
| GBps     | Gigabytes per second                                      |
+----------+-----------------------------------------------------------+
| Gbps     | Gigabits per second                                       |
+----------+-----------------------------------------------------------+
| GCAI     | Ground Camera Ascent Imagery                              |
+----------+-----------------------------------------------------------+
| GCMR     | Ground Configuration Message Request                      |
+----------+-----------------------------------------------------------+
| GCP      | Goddard Corporate Park                                    |
+----------+-----------------------------------------------------------+
| GCTC     | Gargarin Cosmonaut Training Center                        |
+----------+-----------------------------------------------------------+
| GDC      | General DataCom GDC                                       |
+----------+-----------------------------------------------------------+
| GDP      | General Data Products                                     |
+----------+-----------------------------------------------------------+
| GDPRO    | Goldstone Project Requirements Office                     |
+----------+-----------------------------------------------------------+
| GDS      | Ground Data System                                        |
|          |                                                           |
|          | Goldstone                                                 |
+----------+-----------------------------------------------------------+
| GDSCC    | Goldstone Deep Space Communications Complex               |
+----------+-----------------------------------------------------------+
| GEAM     | GE Americom                                               |
+----------+-----------------------------------------------------------+
| GEIP     | Gigabit Ethernet Interface Processor                      |
+----------+-----------------------------------------------------------+
| Geotail  | Japanese-U.S. mission to study magnetospheric processes   |
|          | in distant geomagnetic tail                               |
+----------+-----------------------------------------------------------+
| GFAC     | Goldstone Frequency and Airspace Coordination             |
+----------+-----------------------------------------------------------+
| GFE      | Government-Furnished Equipment                            |
+----------+-----------------------------------------------------------+
| GFF      | Government Furnished Facility                             |
+----------+-----------------------------------------------------------+
| GFY      | Government Fiscal Year                                    |
+----------+-----------------------------------------------------------+
| GGS      | Getronics Government Solutions                            |
+----------+-----------------------------------------------------------+
| GGSG     | Geodynamics Geophysics and Space Geodessy                 |
+----------+-----------------------------------------------------------+
| GHz      | Gigahertz                                                 |
+----------+-----------------------------------------------------------+
| GIANT    | Globally Interconnected Advanced Networked Telepresence   |
+----------+-----------------------------------------------------------+
| GigE     | Gigabit Ethernet                                          |
+----------+-----------------------------------------------------------+
| GISS     | Goddard Institute for Space Studies                       |
+----------+-----------------------------------------------------------+
| GLAST    | Gamma-ray Large Area Space Telescope                      |
+----------+-----------------------------------------------------------+
| GLOBE    | Global Learning and Observations to Benefit the Earth     |
+----------+-----------------------------------------------------------+
| GMT      | Greenwich Mean Time                                       |
+----------+-----------------------------------------------------------+
| GN       | Ground Network                                            |
+----------+-----------------------------------------------------------+
| GOES     | Geosynchronous Operational Environmental Satellite        |
+----------+-----------------------------------------------------------+
| GOPS     | Gateway Operations                                        |
+----------+-----------------------------------------------------------+
| GOTS     | Government Off-The-Shelf                                  |
+----------+-----------------------------------------------------------+
| GP       | Gravity Probe                                             |
+----------+-----------------------------------------------------------+
| GPB      | Gravity Probe B                                           |
+----------+-----------------------------------------------------------+
| GPC      | General Purpose Computer                                  |
+----------+-----------------------------------------------------------+
| GPP      | General-Purpose Post-Processor                            |
+----------+-----------------------------------------------------------+
| GPS      | Global Positioning System                                 |
+----------+-----------------------------------------------------------+
| GRACE    | Gravity Recovery and Climate Experiment                   |
+----------+-----------------------------------------------------------+
| GRC      | Glenn Research Center                                     |
+----------+-----------------------------------------------------------+
| GRC-TL   | Glenn Research Center Technology Laboratory               |
+----------+-----------------------------------------------------------+
| GRE      | Generic Routing Encapsulation                             |
+----------+-----------------------------------------------------------+
| GRGT     | Guam Remote Ground Terminal                               |
+----------+-----------------------------------------------------------+
| GRO      | Gamma Ray Observatory                                     |
+----------+-----------------------------------------------------------+
| GSA      | General Services Administration                           |
+----------+-----------------------------------------------------------+
| GSCB     | Ground Segment Control Board                              |
+----------+-----------------------------------------------------------+
| GSDE     | Ground Software Development Environment                   |
+----------+-----------------------------------------------------------+
| GSFC     | Goddard Space Flight Center                               |
+----------+-----------------------------------------------------------+
| GSIF     | Ground System Interface Facility                          |
+----------+-----------------------------------------------------------+
| GSIP     | Ground System Interface Processor                         |
+----------+-----------------------------------------------------------+
| GSTAR    | General Satellite Earth Launch Vehicle                    |
+----------+-----------------------------------------------------------+
| GTSI     | Government Technology Services, Incorporated              |
+----------+-----------------------------------------------------------+
| GUI      | Graphical User Interface                                  |
+----------+-----------------------------------------------------------+
| GWAC     | Government-Wide Acquisition Contract                      |
+----------+-----------------------------------------------------------+
| HA       | High Availability                                         |
+----------+-----------------------------------------------------------+
| HALOE    | High Altitude Low Orbit Experiment                        |
+----------+-----------------------------------------------------------+
| Hanger   | Building Destination                                      |
| AE       |                                                           |
+----------+-----------------------------------------------------------+
| HBCU     | Historically Black Colleges and Universities              |
+----------+-----------------------------------------------------------+
| HBK      | Hartebeesthoek                                            |
|          |                                                           |
|          | Handbook                                                  |
+----------+-----------------------------------------------------------+
| HC's     | Hierarchy Codes                                           |
+----------+-----------------------------------------------------------+
| HCAT     | Headquarters Columbia Action Team                         |
+----------+-----------------------------------------------------------+
| HCS      | Header Checksum                                           |
+----------+-----------------------------------------------------------+
| HCSA     | Host Center Support Agreements                            |
+----------+-----------------------------------------------------------+
| HD       | High Definition                                           |
+----------+-----------------------------------------------------------+
| HDD      | Hard Disk Drive                                           |
+----------+-----------------------------------------------------------+
| HDRS     | High Data Rate System                                     |
+----------+-----------------------------------------------------------+
| HDTV     | High Definition Television                                |
+----------+-----------------------------------------------------------+
| HECC     | High End Computing Columbia                               |
+----------+-----------------------------------------------------------+
| HEDS     | Human Exploration and Development of Space                |
+----------+-----------------------------------------------------------+
| HEF      | High Efficiency                                           |
+----------+-----------------------------------------------------------+
| HEMI     | Headquarters Enterprise Messaging Initiative              |
+----------+-----------------------------------------------------------+
| HESSI    | High Energy Solar Spectroscopic Imager                    |
+----------+-----------------------------------------------------------+
| HIJ      | TDRSS H, I & J Satellites                                 |
+----------+-----------------------------------------------------------+
| HIRT     | Headquarters Information Technology (IT) Rapid Transition |
+----------+-----------------------------------------------------------+
| HOSC     | Huntsville Operations Support Center                      |
+----------+-----------------------------------------------------------+
| HPA      | High Power Amplifier                                      |
+----------+-----------------------------------------------------------+
| HPOTP    | High Pressure Oxygen Turbo-Pump                           |
+----------+-----------------------------------------------------------+
| HPOV     | HP Openview                                               |
+----------+-----------------------------------------------------------+
| HPOVNNM  | Hewlett Packard Open View Network Node Manager            |
+----------+-----------------------------------------------------------+
| HPR      | High Performance Router                                   |
+----------+-----------------------------------------------------------+
| HPRENS   | High Performance Research and Engineering Networks        |
+----------+-----------------------------------------------------------+
| HQ       | Headquarters                                              |
+----------+-----------------------------------------------------------+
| HSF      | Human Space Flight                                        |
+----------+-----------------------------------------------------------+
| HSM      | Hierarchical Storage Monitoring (HSM)                     |
+----------+-----------------------------------------------------------+
| HSR      | Houston Support Room                                      |
+----------+-----------------------------------------------------------+
| HSSI     | High Speed Serial Interface                               |
+----------+-----------------------------------------------------------+
| HST      | Hubble Space Telescope                                    |
+----------+-----------------------------------------------------------+
| HSTOCC   | HST Operations Control Center                             |
+----------+-----------------------------------------------------------+
| HTML     | Hypertext Markup Language                                 |
+----------+-----------------------------------------------------------+
| HTTP     | Hypertext Transfer Protocol                               |
+----------+-----------------------------------------------------------+
| HviDS    | HOSC Video Distribution System                            |
+----------+-----------------------------------------------------------+
| HvoDS    | HOSC Voice Distribution System                            |
+----------+-----------------------------------------------------------+
| HW or    | Hardware                                                  |
| H/W      |                                                           |
+----------+-----------------------------------------------------------+
| I/O      | Input/Output                                              |
+----------+-----------------------------------------------------------+
| I3TEL    | Integrated Intelligent Information for Telecommunications |
+----------+-----------------------------------------------------------+
| IAF      | International Aeronautical Federation                     |
+----------+-----------------------------------------------------------+
| IAN      | Institutional Area Network                                |
+----------+-----------------------------------------------------------+
| IBM      | International Business Machines                           |
+----------+-----------------------------------------------------------+
| IBMP     | Institute of Biomedical Problems                          |
+----------+-----------------------------------------------------------+
| ICAT     | Inter-company Accounting Transfer                         |
+----------+-----------------------------------------------------------+
| ICBM     | Intercontinental Ballistic Missile                        |
+----------+-----------------------------------------------------------+
| ICD      | Interface Control Document                                |
+----------+-----------------------------------------------------------+
| ICE      | Refers to the monitoring of actual ice on the orbital     |
|          | prior to launch                                           |
+----------+-----------------------------------------------------------+
| ICESat   | Ice, Cloud, and Land Elevation Satellite                  |
+----------+-----------------------------------------------------------+
| ICM      | Interim Control Module                                    |
+----------+-----------------------------------------------------------+
| ICMP     | Internet Control Message Protocol                         |
+----------+-----------------------------------------------------------+
| ID/IR    | Intrusion Detection/Incident Report                       |
+----------+-----------------------------------------------------------+
| IDAC     | Integrated Digital Analog Converter                       |
+----------+-----------------------------------------------------------+
| IDE      | Independent Development Environment                       |
+----------+-----------------------------------------------------------+
| IDEA     | ISS Downlink Enhancement Architecture                     |
+----------+-----------------------------------------------------------+
| IDIQ     | Indefinite Delivery/Indefinite Quantity                   |
+----------+-----------------------------------------------------------+
| IDMS     | Information and Data Management System                    |
+----------+-----------------------------------------------------------+
| IDNX     | Integrated Digital Network Exchange                       |
+----------+-----------------------------------------------------------+
| IDR      | Informal Design Review                                    |
+----------+-----------------------------------------------------------+
| IDS      | Intrusion Detection System                                |
+----------+-----------------------------------------------------------+
| IEEE     | Institute of Electrical and Electronic Engineers          |
+----------+-----------------------------------------------------------+
| IEM      | Integrated Enterprise Management                          |
+----------+-----------------------------------------------------------+
| IEMP     | Integrated Enterprise Management Program                  |
+----------+-----------------------------------------------------------+
| IETF     | Internet Engineering Task Force                           |
+----------+-----------------------------------------------------------+
| IFM      | Integrated Financial Management                           |
+----------+-----------------------------------------------------------+
| IFMP     | Integrated Financial Management Program (now Integrated   |
|          | Enterprise Management Program)                            |
+----------+-----------------------------------------------------------+
| IFS      | Internet File System                                      |
+----------+-----------------------------------------------------------+
| IG       | Inspector General                                         |
+----------+-----------------------------------------------------------+
| IG       | Instrumentation Group                                     |
+----------+-----------------------------------------------------------+
| IGW      | Integrated Graphics Workstation                           |
+----------+-----------------------------------------------------------+
| IIJ      | Internet Initiative Japan                                 |
+----------+-----------------------------------------------------------+
| IIS      | Internet Information Server                               |
+----------+-----------------------------------------------------------+
| IKI      | Institute Kosmicheskikh Issledoranii (the Space Research  |
|          | Institute/ Russian Academy of Sciences)                   |
+----------+-----------------------------------------------------------+
| IM       | Instant Meeting                                           |
+----------+-----------------------------------------------------------+
| IMCC     | Information Mission Control Center                        |
+----------+-----------------------------------------------------------+
| IMCCA    | Interactive Multimedia and Collaborative Communications   |
|          | Alliance                                                  |
+----------+-----------------------------------------------------------+
| IMCS     | Integrated Management Control System                      |
+----------+-----------------------------------------------------------+
| IMOC     | Integrated Mission Operations Center                      |
+----------+-----------------------------------------------------------+
| IMP      | Integrated Management Plan                                |
+----------+-----------------------------------------------------------+
| INL      | Integrated Network Laboratory                             |
+----------+-----------------------------------------------------------+
| InSAR    | Interferometric Synthetic Aperture Radar                  |
+----------+-----------------------------------------------------------+
| IOA      | Integrated Operations Architecture                        |
+----------+-----------------------------------------------------------+
| # IONet  | Integrated Operations Network                             |
+----------+-----------------------------------------------------------+
| # Ionet  | Internet Protocol Operational Network                     |
+----------+-----------------------------------------------------------+
| IOR      | Increment Operations Review                               |
+----------+-----------------------------------------------------------+
| IOS      | Internet Operating System                                 |
|          |                                                           |
|          | Integrated Operations systems                             |
|          |                                                           |
|          | Internetwork Operating System                             |
+----------+-----------------------------------------------------------+
| IP       | Internet Protocol                                         |
|          |                                                           |
|          | International Partners                                    |
+----------+-----------------------------------------------------------+
| IPAC     | Intra-governmental Payments and Collections               |
+----------+-----------------------------------------------------------+
| # IPAM   | Internet Protocol Address Management                      |
+----------+-----------------------------------------------------------+
| # Iperf  | Name of tool                                              |
+----------+-----------------------------------------------------------+
| IPL      | Interplanetary Physics Lab                                |
+----------+-----------------------------------------------------------+
| IPNOC    | Internet Protocol Network Operations Center               |
+----------+-----------------------------------------------------------+
| IPS      | Integrated Planning System                                |
+----------+-----------------------------------------------------------+
| IPSEC    | Internet Protocol Security                                |
+----------+-----------------------------------------------------------+
| IPTV     | Internet Protocol Television                              |
+----------+-----------------------------------------------------------+
| IPTX     | Internet Protocol Transmission                            |
+----------+-----------------------------------------------------------+
| IPV4     | Internet Protocol Version 4                               |
+----------+-----------------------------------------------------------+
| IPV6     | Internet Protocol Version 6                               |
+----------+-----------------------------------------------------------+
| IPX      | Internetwork Packet Exchange                              |
+----------+-----------------------------------------------------------+
| IR       | Infrared                                                  |
+----------+-----------------------------------------------------------+
| IRD      | Information Resources Directorate                         |
+----------+-----------------------------------------------------------+
| IRIG     | Inter-Range Instrumentation Group                         |
+----------+-----------------------------------------------------------+
| IRSR     | Internal Relocation Service Request System                |
+----------+-----------------------------------------------------------+
| ISA      | Industry Standard Architecture                            |
+----------+-----------------------------------------------------------+
| ISC      | Integrated Secure Circuit                                 |
+----------+-----------------------------------------------------------+
| ISD      | Information Systems Directorate                           |
+----------+-----------------------------------------------------------+
| ISDN     | Integrated Services Digital Network                       |
+----------+-----------------------------------------------------------+
| ISIL     | ISS Software Integration Laboratory                       |
+----------+-----------------------------------------------------------+
| ISM      | Integrated System Management                              |
+----------+-----------------------------------------------------------+
| ISO      | International Standards Organization                      |
+----------+-----------------------------------------------------------+
| IsoWAN   | Isolated Wide Area Network                                |
+----------+-----------------------------------------------------------+
| ISP      | Internet Service Provider                                 |
+----------+-----------------------------------------------------------+
| ISR      | Internal Service Request                                  |
|          |                                                           |
|          | Interim Systems Review                                    |
|          |                                                           |
|          | Initial Systems Review                                    |
+----------+-----------------------------------------------------------+
| ISRP     | Instrumentation Radar Support Program                     |
+----------+-----------------------------------------------------------+
| ISS      | International Space Station                               |
+----------+-----------------------------------------------------------+
| ISSO     | Information Systems Services Office                       |
+----------+-----------------------------------------------------------+
| ISSPO    | International Space Station Program Office                |
+----------+-----------------------------------------------------------+
| ISTP     | International Solar Terrestrial Physics                   |
+----------+-----------------------------------------------------------+
| ISU      | Integrated Service Unit                                   |
+----------+-----------------------------------------------------------+
| IT       | Information Technology                                    |
+----------+-----------------------------------------------------------+
| ITAP     | Information Technology Assessment Plan                    |
+----------+-----------------------------------------------------------+
| ITAPS    | Information Technology Acquisition Planning Summary       |
+----------+-----------------------------------------------------------+
| ITCOP    | Interagency, Tracking, Communications, and Operations     |
|          | Panel                                                     |
+----------+-----------------------------------------------------------+
| ITMC     | International Telecommunications Management Center        |
+----------+-----------------------------------------------------------+
| ITOS     | Integrated Test and Operations System                     |
+----------+-----------------------------------------------------------+
| ITP      | Information Technology Plan                               |
+----------+-----------------------------------------------------------+
| ITS      | Information Technology Security                           |
+----------+-----------------------------------------------------------+
| ITSC     | Information Technology Steering Council                   |
+----------+-----------------------------------------------------------+
| ITSM     | Information Technology Security Manager                   |
+----------+-----------------------------------------------------------+
| ITU      | International Teleconferencing Union                      |
+----------+-----------------------------------------------------------+
| ITU-T    | International Telecommunication Union Telecommunication   |
|          | Standardization Sector                                    |
+----------+-----------------------------------------------------------+
| IUS      | Interim Upper Stage or Inertial Upper Stage               |
+----------+-----------------------------------------------------------+
| IV & V   | Independent Verification and Validation                   |
+----------+-----------------------------------------------------------+
| IV &VF   | Independent Verification and Validation Facility          |
+----------+-----------------------------------------------------------+
| IvoDS    | Internet Voice Distribution System                        |
+----------+-----------------------------------------------------------+
| JANET    | Joint Academic Network                                    |
+----------+-----------------------------------------------------------+
| JASON    | Not an acronym                                            |
+----------+-----------------------------------------------------------+
| JASON-1  | The JASON Project is an organization engages students in  |
|          | scientific research and expeditions led by leading        |
|          | scientists. Named after the mythical character Jason of   |
|          | the Argonauts.                                            |
+----------+-----------------------------------------------------------+
| JAXA     | Japanese Aerospace eXploration Agency                     |
+----------+-----------------------------------------------------------+
| JDBC     | Java Database Connectivity                                |
+----------+-----------------------------------------------------------+
| JDMTA    | Jonathan-Dickinson Missile Tracking Annex                 |
+----------+-----------------------------------------------------------+
| JET      | Joint Engineering Team                                    |
+----------+-----------------------------------------------------------+
| JETS     | JSC Enabling Technology and Security                      |
+----------+-----------------------------------------------------------+
| JHU      | John Hopkins University                                   |
+----------+-----------------------------------------------------------+
| JIMMS    | JSC Information Management and Media Services             |
+----------+-----------------------------------------------------------+
| JLOP     | Joint Local Operating Procedure                           |
+----------+-----------------------------------------------------------+
| JPEG     | Joint Photographic Experts Group                          |
+----------+-----------------------------------------------------------+
| JPL      | Jet Propulsion Laboratory                                 |
+----------+-----------------------------------------------------------+
| JSC      | Johnson Space Center                                      |
+----------+-----------------------------------------------------------+
| JSCAT    | Spacecraft                                                |
+----------+-----------------------------------------------------------+
| K or KB  | Kilobyte                                                  |
+----------+-----------------------------------------------------------+
| KAFB     | Kirtland Air Force Base                                   |
+----------+-----------------------------------------------------------+
| Kbps     | Kilobits per second                                       |
+----------+-----------------------------------------------------------+
| KG       | Encryption equipment                                      |
+----------+-----------------------------------------------------------+
| KICS     | Kennedy Integrated Communications Services                |
+----------+-----------------------------------------------------------+
| KLMSDS   | Kongsberg Lockheed Martin Space Data Services             |
+----------+-----------------------------------------------------------+
| KSA      | Ku-Band Single Access                                     |
+----------+-----------------------------------------------------------+
| KSC      | Kennedy Space Center                                      |
+----------+-----------------------------------------------------------+
| KVM      | Keyboard, Video, Monitor                                  |
+----------+-----------------------------------------------------------+
| KW       | Kilowatt                                                  |
+----------+-----------------------------------------------------------+
| L2       | Layer 2                                                   |
+----------+-----------------------------------------------------------+
| L3       | Layer 3                                                   |
+----------+-----------------------------------------------------------+
| LAN      | Local Area Network                                        |
+----------+-----------------------------------------------------------+
| LANDSAT  | Land Remote-Sensing Satellite                             |
+----------+-----------------------------------------------------------+
| LANM     | LANDSAT, Lanham, MD                                       |
+----------+-----------------------------------------------------------+
| LaRC     | Langley Research Center                                   |
+----------+-----------------------------------------------------------+
| LASP     | Laboratory for Astronomy and Solar Physics                |
+----------+-----------------------------------------------------------+
| LATA     | Local Access Transport Area                               |
+----------+-----------------------------------------------------------+
| LBV      | Low Bandwidth Video                                       |
+----------+-----------------------------------------------------------+
| LCC      | Launch Commit Criteria                                    |
|          |                                                           |
|          | Life Cycle Cost                                           |
|          |                                                           |
|          | Launch Control Center                                     |
+----------+-----------------------------------------------------------+
| LCD      | Liquid Crystal Display                                    |
+----------+-----------------------------------------------------------+
| LCMT     | Lockheed Martin facility                                  |
+----------+-----------------------------------------------------------+
| LCRS     | Large Conference Room System                              |
+----------+-----------------------------------------------------------+
| LD       | Long Distance                                             |
+----------+-----------------------------------------------------------+
| LDAP     | Lightweight Directory Access Protocol                     |
+----------+-----------------------------------------------------------+
| LDAR     | Lightning Detection And Ranging                           |
+----------+-----------------------------------------------------------+
| LDB      | Long Duration Balloon                                     |
+----------+-----------------------------------------------------------+
| LDBP     | Long-Duration Balloon Program                             |
+----------+-----------------------------------------------------------+
| LEC      | Local Exchange Carrier                                    |
+----------+-----------------------------------------------------------+
| LEO-T    | Low Earth Orbital -- Terrestrial                          |
+----------+-----------------------------------------------------------+
| LeRC     | Lewis Research Center                                     |
+----------+-----------------------------------------------------------+
| LERG     | Local Exchange Routing Guide                              |
+----------+-----------------------------------------------------------+
| LIMS     | Logistics Management Inventory System                     |
+----------+-----------------------------------------------------------+
| LIPPS    | LANDSAT IP Processing System                              |
+----------+-----------------------------------------------------------+
| LITT     | Littleton, Colorado                                       |
+----------+-----------------------------------------------------------+
| LIU      | Line Interface Unit                                       |
+----------+-----------------------------------------------------------+
| LM       | Lockheed Martin                                           |
+----------+-----------------------------------------------------------+
| LMA      | Multiple Access                                           |
+----------+-----------------------------------------------------------+
| LMCO     | Lockheed Martin Corporation                               |
+----------+-----------------------------------------------------------+
| LMIT     | Lockheed Martin Information Technology                    |
+----------+-----------------------------------------------------------+
| LMMSI    | Lockheed Martin Missiles and Space Inc.                   |
+----------+-----------------------------------------------------------+
| LMSO     | Lockheed Martin Space Operations                          |
+----------+-----------------------------------------------------------+
| LMSOC    | Lockheed Martin Space Operations Company                  |
+----------+-----------------------------------------------------------+
| LMT      | Local Maintenance Terminal                                |
+----------+-----------------------------------------------------------+
| LN       | Last Name                                                 |
+----------+-----------------------------------------------------------+
| LOA      | Letter of Agreement                                       |
+----------+-----------------------------------------------------------+
| LOE      | Level of Effort                                           |
+----------+-----------------------------------------------------------+
| LOP      | Local Operating Procedure                                 |
+----------+-----------------------------------------------------------+
| LPA      | Logical Port Address                                      |
+----------+-----------------------------------------------------------+
| LPAR     | Logical Partitioning                                      |
+----------+-----------------------------------------------------------+
| LPT      | Low Power Transceiver                                     |
+----------+-----------------------------------------------------------+
| LRC      | Langley Research Center                                   |
+----------+-----------------------------------------------------------+
| LRCS     | Large Room Conferencing System                            |
+----------+-----------------------------------------------------------+
| LSAT     | Land Remote Sensing Satellite                             |
+----------+-----------------------------------------------------------+
| LSD      | Logistics Supply Depot                                    |
|          |                                                           |
|          | Low Speed Data                                            |
+----------+-----------------------------------------------------------+
| LSOS     | Limited Station Operations System                         |
+----------+-----------------------------------------------------------+
| LWCA     | Lost Workday Cases Away                                   |
+----------+-----------------------------------------------------------+
| LZ       | Level-Zero                                                |
+----------+-----------------------------------------------------------+
| LZP      | Level Zero Processing                                     |
+----------+-----------------------------------------------------------+
| LZPF     | Level-Zero Processing Facility                            |
+----------+-----------------------------------------------------------+
| M&O      | Maintenance and Operations                                |
+----------+-----------------------------------------------------------+
| MA       | Multiple Accesses                                         |
+----------+-----------------------------------------------------------+
| MAC      | Move-Add-Change                                           |
+----------+-----------------------------------------------------------+
| MAD      | Call sign for Madrid, Spain, Ground Network Tracking      |
|          | Station                                                   |
+----------+-----------------------------------------------------------+
| MAE      | Metropolitan Access Exchange                              |
+----------+-----------------------------------------------------------+
| MAE      | Metropolitan Area Exchange                                |
+----------+-----------------------------------------------------------+
| MAF      | Michoud Assembly Facility                                 |
+----------+-----------------------------------------------------------+
| MAN      | Metropolitan Area Network                                 |
+----------+-----------------------------------------------------------+
| MAO      | Management and Assessment Office                          |
+----------+-----------------------------------------------------------+
| MAP      | Microwave Anisotropy Probe                                |
+----------+-----------------------------------------------------------+
| MAX      | Mid Atlantic crossroads                                   |
+----------+-----------------------------------------------------------+
| MB       | Megabyte                                                  |
+----------+-----------------------------------------------------------+
| mBGP     | Multi-protocol Border Gateway Protocol                    |
+----------+-----------------------------------------------------------+
| Mbone    | Multicast Backbone                                        |
+----------+-----------------------------------------------------------+
| Mbps     | Megabits per second                                       |
+----------+-----------------------------------------------------------+
| MBR      | MIL/BDA Re-Engineering                                    |
+----------+-----------------------------------------------------------+
| MBX      | ? Narrow band ATM Concentrator                            |
+----------+-----------------------------------------------------------+
| Mcast    | Multicast                                                 |
+----------+-----------------------------------------------------------+
| MCC      | Mission Control Center                                    |
+----------+-----------------------------------------------------------+
| MCCB     | MSFC Change Control Board                                 |
+----------+-----------------------------------------------------------+
| MCC-H    | Mission Control Center - Houston                          |
+----------+-----------------------------------------------------------+
| MCC-M    | Mission Control Center - Moscow                           |
+----------+-----------------------------------------------------------+
| MCDTV    | Multi-Channel Digital Television                          |
+----------+-----------------------------------------------------------+
| MCG      | Mjave Coordinating Group                                  |
+----------+-----------------------------------------------------------+
| MCI      | MCI                                                       |
+----------+-----------------------------------------------------------+
| MCIP     | Mission Critical Internet Protocol                        |
+----------+-----------------------------------------------------------+
| MCM      | Mission Communications Manager                            |
+----------+-----------------------------------------------------------+
| MCO      | Mars Climate Orbiter                                      |
+----------+-----------------------------------------------------------+
| MCS      | Multi-Point Communication Service                         |
+----------+-----------------------------------------------------------+
| MCU      | Multipoint Control Unit                                   |
|          |                                                           |
|          | Multipoint Conferencing Unit                              |
+----------+-----------------------------------------------------------+
| MCWG     | Mission Communications Working Group                      |
+----------+-----------------------------------------------------------+
| MDM      | Multiplexer/Demultiplexer                                 |
+----------+-----------------------------------------------------------+
| MDP      | Multicast Discovery Protocol                              |
+----------+-----------------------------------------------------------+
| MDSCC    | Madrid Deep Space Communications Complex                  |
+----------+-----------------------------------------------------------+
| MECO     | Main Engine Cut Off                                       |
+----------+-----------------------------------------------------------+
| MEI      | Muniz Engineering Inc. - JETS prime contractor            |
+----------+-----------------------------------------------------------+
| MEI      | Minimum Essential Infrastructure                          |
+----------+-----------------------------------------------------------+
| MEMERGE  | Main Engine Merge Software                                |
+----------+-----------------------------------------------------------+
| MER      | Mars Exploration Rover                                    |
+----------+-----------------------------------------------------------+
| MERN     | Metropolitan Research and Education Network               |
+----------+-----------------------------------------------------------+
| METEOSAT | Metrological Satellite                                    |
+----------+-----------------------------------------------------------+
| MEWS     | Mission Evaluation Work Station                           |
+----------+-----------------------------------------------------------+
| MFR      | Multifunction Receiver                                    |
+----------+-----------------------------------------------------------+
| MGC      | Media Gateway Controller                                  |
+----------+-----------------------------------------------------------+
| MGE      | (3 letter company name -- does not stand for anything)    |
+----------+-----------------------------------------------------------+
| MGS      | Mars Global Surveyor                                      |
|          |                                                           |
|          | McMurdo Ground Station                                    |
+----------+-----------------------------------------------------------+
| MGX      | Multi-service Gateway Exchange                            |
+----------+-----------------------------------------------------------+
| MHz      | Megahertz                                                 |
+----------+-----------------------------------------------------------+
| MIB      | Management Information Base                               |
+----------+-----------------------------------------------------------+
| MIC      | Management Information Center                             |
|          |                                                           |
|          | Microphone                                                |
+----------+-----------------------------------------------------------+
| MICS     | Management Information and Control System                 |
+----------+-----------------------------------------------------------+
| MIDDS    | Meteorological Information Data Distribution System       |
+----------+-----------------------------------------------------------+
| # MIDEX  | Medium-Class Explorer                                     |
+----------+-----------------------------------------------------------+
| MIL      | Merritt Island Ground Station                             |
+----------+-----------------------------------------------------------+
| MILA     | Merritt Island Launch Area                                |
+----------+-----------------------------------------------------------+
| MIT      | Mishap Investigation Team                                 |
|          |                                                           |
|          | Massachusetts Institute of Technology                     |
+----------+-----------------------------------------------------------+
| MIX      | Marshall Image Exchange                                   |
+----------+-----------------------------------------------------------+
| MLP      | Mobile Launch Pad                                         |
+----------+-----------------------------------------------------------+
| MLV      | Multi-purpose Launch Vehicle                              |
+----------+-----------------------------------------------------------+
| MMAC     | Man-Months At Completion                                  |
+----------+-----------------------------------------------------------+
| MMF      | Multi-mode Fiber                                          |
+----------+-----------------------------------------------------------+
| MMS      | Magnetospheric Multiscale                                 |
+----------+-----------------------------------------------------------+
| MMT      | Mission Management Team                                   |
+----------+-----------------------------------------------------------+
| MN       | Middle Name                                               |
+----------+-----------------------------------------------------------+
| MNM      | Mission Network Modernization                             |
+----------+-----------------------------------------------------------+
| MOA      | Memorandum of Agreement                                   |
+----------+-----------------------------------------------------------+
| MOB      | Minority Owned Business                                   |
+----------+-----------------------------------------------------------+
| MOC      | Mission Operations Complex                                |
|          |                                                           |
|          | Mission Operations Center                                 |
+----------+-----------------------------------------------------------+
| MOCC     | Mission Operation Control Center                          |
+----------+-----------------------------------------------------------+
| MOD      | Mission Operations Directive                              |
+----------+-----------------------------------------------------------+
| MODIS    | Moderate Resolution Imaging Spectroradiometer             |
+----------+-----------------------------------------------------------+
| MOIP     | Mission Operations Integration and Planning               |
+----------+-----------------------------------------------------------+
| MOMS     | Mission Operations and Mission Services                   |
+----------+-----------------------------------------------------------+
| MONS     | # Mission Outage Notification System                      |
+----------+-----------------------------------------------------------+
| MOPS     | Mission Operations Planning System                        |
+----------+-----------------------------------------------------------+
| MORR     | Marshall Operational Readiness Review                     |
+----------+-----------------------------------------------------------+
| MORR     | Mission Operational Readiness Review                      |
+----------+-----------------------------------------------------------+
| MOSPF    | Multi-cast Open Shortest Path First                       |
+----------+-----------------------------------------------------------+
| MOU      | Memorandum of Understanding                               |
+----------+-----------------------------------------------------------+
| MOVE     | Mission Operations Voice Enhancement                      |
+----------+-----------------------------------------------------------+
| MPA      | Metric Pointing Assembly                                  |
+----------+-----------------------------------------------------------+
| MPEG     | Moving Picture Export Group                               |
+----------+-----------------------------------------------------------+
| MPL      | Mars Polar Lander                                         |
+----------+-----------------------------------------------------------+
| MPLS     | Multiprotocol Label Switching                             |
+----------+-----------------------------------------------------------+
| MPV      | Manual Procedure Viewer                                   |
+----------+-----------------------------------------------------------+
| MRC      | Monthly Recurring Cost                                    |
|          |                                                           |
|          | Madison Research Corporation                              |
+----------+-----------------------------------------------------------+
| MRDS     | Mission Routed Data Service                               |
+----------+-----------------------------------------------------------+
| MREN     | Metropolitan Research and Education Network               |
+----------+-----------------------------------------------------------+
| MRF      | Maintenance Repair Facility                               |
+----------+-----------------------------------------------------------+
| MRR      | Mission Readiness Review                                  |
+----------+-----------------------------------------------------------+
| MRWG     | Mission Requirements Working Group                        |
+----------+-----------------------------------------------------------+
| MS       | Microsoft                                                 |
+----------+-----------------------------------------------------------+
| ms       | Millisecond                                               |
+----------+-----------------------------------------------------------+
| MSAT     | Multisat                                                  |
+----------+-----------------------------------------------------------+
| MSC      | Mission Support Contract                                  |
+----------+-----------------------------------------------------------+
| MSFC     | George C. Marshall Space Flight Center                    |
+----------+-----------------------------------------------------------+
| MSFI     | Marshall Space Flight Center - Institutional              |
+----------+-----------------------------------------------------------+
| MSID     | Measurement Stimuli Identifiers                           |
+----------+-----------------------------------------------------------+
| MSM      | Mission System Manager                                    |
+----------+-----------------------------------------------------------+
| MSN      | Mission                                                   |
+----------+-----------------------------------------------------------+
| MSOC     | JSC Mission Support Operations Contract                   |
+----------+-----------------------------------------------------------+
| MSOP     | Mars Surveyor Operations Project                          |
+----------+-----------------------------------------------------------+
| MSPP     | Multi Service Provision Platform                          |
+----------+-----------------------------------------------------------+
| MSRD     | Mission Support Routed Data                               |
+----------+-----------------------------------------------------------+
| MSRDS    | Mission Support Routed Data Service                       |
+----------+-----------------------------------------------------------+
| MSS      | Mississippi Spaces Services                               |
+----------+-----------------------------------------------------------+
| MSSS     | Malin Space Science Systems                               |
+----------+-----------------------------------------------------------+
| MSTA     | Multi-mission Support Training Activity                   |
|          |                                                           |
|          | Mission Services Training Activities                      |
+----------+-----------------------------------------------------------+
| MTA      | Metric Tracking Assembly                                  |
+----------+-----------------------------------------------------------+
| MTCC     | Moffett Training Conference Center                        |
+----------+-----------------------------------------------------------+
| MTRS     | McMurdo TDRSS Relay System                                |
+----------+-----------------------------------------------------------+
| MTTR     | Mean Time to Repair/Replace                               |
+----------+-----------------------------------------------------------+
| MUG      | Multicast Unicast Gateway                                 |
+----------+-----------------------------------------------------------+
| Mux      | Multiplexer                                               |
+----------+-----------------------------------------------------------+
| MVCS     | Mission Voice Conferencing System                         |
+----------+-----------------------------------------------------------+
| MWO      | Maximo Work Order                                         |
+----------+-----------------------------------------------------------+
| NACAIT   | Network and Communications Analysis and Integration Team  |
+----------+-----------------------------------------------------------+
| NACB     | Network Access Control Board                              |
+----------+-----------------------------------------------------------+
| NACC     | NASA Automated Data Processing (ADP) Consolidation Center |
+----------+-----------------------------------------------------------+
| NAM      | Network Advisory Message                                  |
+----------+-----------------------------------------------------------+
| NANOG    | North American Network Operator Group                     |
+----------+-----------------------------------------------------------+
| NAP      | Navigation Analysis Program                               |
+----------+-----------------------------------------------------------+
| NAPT     | NISN Performance Assessment Team                          |
+----------+-----------------------------------------------------------+
| NAR      | Non-Advocate Review                                       |
+----------+-----------------------------------------------------------+
| NARNet   | Notice of Ammunition Reclassification Network             |
+----------+-----------------------------------------------------------+
| NAS      | Numerical Aerodynamic simulation                          |
+----------+-----------------------------------------------------------+
| NAS      | Network Attached Storage                                  |
+----------+-----------------------------------------------------------+
| NASA     | National Aeronautics and Space Administration             |
+----------+-----------------------------------------------------------+
| NASAnet  | NASA Network                                              |
+----------+-----------------------------------------------------------+
| Nascom   | NASA Communications                                       |
+----------+-----------------------------------------------------------+
| NASDA    | National Space Development Agency of Japan                |
+----------+-----------------------------------------------------------+
| NASIRC   | NASA Automated Systems Incident Response Capability       |
+----------+-----------------------------------------------------------+
| NASLAN   | NASA Advanced Supercomputing LAN                          |
+----------+-----------------------------------------------------------+
| NAT      | Network Address Translation                               |
+----------+-----------------------------------------------------------+
| NBC      | National Business Center                                  |
+----------+-----------------------------------------------------------+
| NCARS    | NISN Cyber Attack Response System                         |
+----------+-----------------------------------------------------------+
| NCC      | Network Control Center                                    |
+----------+-----------------------------------------------------------+
| NCCB     | NISN Change Control Board                                 |
+----------+-----------------------------------------------------------+
| NCDDC    | National Coastal Data Development Center                  |
+----------+-----------------------------------------------------------+
| NCI      | NASA Collaborative Infrastructure                         |
+----------+-----------------------------------------------------------+
| NCM      | Network Configuration Management                          |
+----------+-----------------------------------------------------------+
| NCMS     | Network Configuration Management System                   |
+----------+-----------------------------------------------------------+
| NCP      | Network Control Project                                   |
+----------+-----------------------------------------------------------+
| NCPS     | Network Command Processor System                          |
+----------+-----------------------------------------------------------+
| NCR      | NISN Center Representative                                |
+----------+-----------------------------------------------------------+
| NCSA     | NISN Customer Scheduling Awareness                        |
+----------+-----------------------------------------------------------+
| NDBC     | National Data Buoy Center                                 |
+----------+-----------------------------------------------------------+
| NDC      | NASA Data Center                                          |
+----------+-----------------------------------------------------------+
| NEC      | Network Equipment Corp                                    |
+----------+-----------------------------------------------------------+
| NENS     | # Near Earth Network Services                             |
+----------+-----------------------------------------------------------+
| NERD     | # NASCOM Engineering Review and Design                    |
+----------+-----------------------------------------------------------+
| NESC     | # NASA Engineering and Safety Center                      |
+----------+-----------------------------------------------------------+
| NESDIS   | National Environmental Satellite, Data, and Information   |
|          | Service                                                   |
+----------+-----------------------------------------------------------+
| NETSCOUT | (company name -- does not stand for anything)             |
+----------+-----------------------------------------------------------+
| NGIX     | Next Generation Internet Exchange                         |
+----------+-----------------------------------------------------------+
| NGLT     | Next Generation Launch Technology                         |
+----------+-----------------------------------------------------------+
| NGST     | Next Generation Space Telescope                           |
+----------+-----------------------------------------------------------+
| NHB      | NASA Handbook                                             |
+----------+-----------------------------------------------------------+
| NI       | National Instruments                                      |
+----------+-----------------------------------------------------------+
| NIB      | Network Interface Board                                   |
+----------+-----------------------------------------------------------+
| NIC      | Network Integration Center                                |
+----------+-----------------------------------------------------------+
| NIIS     | NISN Integrated Information Systems                       |
+----------+-----------------------------------------------------------+
| NILE     | Nascom Internet Laboratory Environment                    |
+----------+-----------------------------------------------------------+
| NIS      | Network Information Server                                |
|          |                                                           |
|          | Network Information Service                               |
+----------+-----------------------------------------------------------+
| NISC     | NASA Information Support Center                           |
+----------+-----------------------------------------------------------+
| NISE     | NASA Institutional Service Environment                    |
+----------+-----------------------------------------------------------+
| NISN     | NASA Integrated Services Network                          |
+----------+-----------------------------------------------------------+
| NISSU    | NASA Infrastructure System Services Utility               |
+----------+-----------------------------------------------------------+
| NIST     | National Institute of Standard and Technology             |
+----------+-----------------------------------------------------------+
| NLB      | Network Load Balancing                                    |
+----------+-----------------------------------------------------------+
| NLIC     | Nascom LAN Interface Card                                 |
+----------+-----------------------------------------------------------+
| NMC      | Network Management Center                                 |
+----------+-----------------------------------------------------------+
| NMCC     | Network Management Change Control                         |
+----------+-----------------------------------------------------------+
| NMCM     | Network Management and Context Monitoring                 |
+----------+-----------------------------------------------------------+
| NMDS     | Network Management Data Service                           |
+----------+-----------------------------------------------------------+
| NME      | Non-Maintainable Equipment                                |
+----------+-----------------------------------------------------------+
| NMERP    | Non-Maintainable Equipment Replacement Plan               |
+----------+-----------------------------------------------------------+
| NMSU     | New Mexico State University                               |
+----------+-----------------------------------------------------------+
| NNM      | Network Node Manager                                      |
+----------+-----------------------------------------------------------+
| NNSG     | NISN Network Support Group                                |
+----------+-----------------------------------------------------------+
| NOAA     | National Oceanic and Atmospheric Administration           |
+----------+-----------------------------------------------------------+
| NOC      | Network Operations Center                                 |
+----------+-----------------------------------------------------------+
| NOCC     | Network Operations Control Center                         |
+----------+-----------------------------------------------------------+
| NOMAD    | NASA Operations Messaging and Directory                   |
+----------+-----------------------------------------------------------+
| NOMC     | NASCOM Operations Management Center                       |
+----------+-----------------------------------------------------------+
| NOPE     | Network Operations Project Engineer                       |
+----------+-----------------------------------------------------------+
| NORAD    | USAF's Satellite Tracking Network                         |
+----------+-----------------------------------------------------------+
| NOSL     | Network Operation Systems Lab (New name of the INL)       |
+----------+-----------------------------------------------------------+
| NPD      | NASA Policy Directive                                     |
+----------+-----------------------------------------------------------+
| NPE      | Network Processing Engine                                 |
+----------+-----------------------------------------------------------+
| NPG      | NASA Procedures and Guidelines                            |
+----------+-----------------------------------------------------------+
| NPN      | NISN Prototype Network                                    |
+----------+-----------------------------------------------------------+
| NPO      | National Polar-Orbiting                                   |
+----------+-----------------------------------------------------------+
| NPOESS   | National Polar-orbiting Operational Environmental         |
|          | Satellite System                                          |
+----------+-----------------------------------------------------------+
| NPR      | NASA Procedure Requirement                                |
+----------+-----------------------------------------------------------+
| NPRD     | Network Program Requirements Document                     |
+----------+-----------------------------------------------------------+
| NREN     | National Research and Education Network                   |
|          |                                                           |
|          | National Research and Engineering Network                 |
+----------+-----------------------------------------------------------+
| NRL      | Naval Research Laboratory                                 |
+----------+-----------------------------------------------------------+
| NRO      | National Reconnaissance Office                            |
+----------+-----------------------------------------------------------+
| NRP      | NASA Resource Protection                                  |
+----------+-----------------------------------------------------------+
| NRS      | NCI Resource Scheduler                                    |
+----------+-----------------------------------------------------------+
| NSA      | National Security Agency                                  |
+----------+-----------------------------------------------------------+
| NSAP     | Network Service Assurance Plan                            |
+----------+-----------------------------------------------------------+
| NSAS     | NISN Services Assessment Study                            |
+----------+-----------------------------------------------------------+
| NSAT     | NISN Service Assessment Team                              |
+----------+-----------------------------------------------------------+
| NSBF     | National Scientific Balloon Facility                      |
+----------+-----------------------------------------------------------+
| NSBFTX   | National Scientific Balloon Facility, Palestine, Texas    |
+----------+-----------------------------------------------------------+
| NSD      | NISN Services Document                                    |
+----------+-----------------------------------------------------------+
| NSF      | National Science Foundation                               |
+----------+-----------------------------------------------------------+
| NSG      | NISN Services Group                                       |
|          |                                                           |
|          | Network Support Group                                     |
|          |                                                           |
|          | Network Services Group                                    |
+----------+-----------------------------------------------------------+
| NSI      | NASA Science Internet                                     |
+----------+-----------------------------------------------------------+
| NSIDC    | National Snow and Ice Data Center                         |
+----------+-----------------------------------------------------------+
| NSLD     | NASA Shuttle Logistics Depot                              |
+----------+-----------------------------------------------------------+
| NSM      | NISN Services Manager                                     |
+----------+-----------------------------------------------------------+
| N-SOC    | NISN Security Operations Center                           |
+----------+-----------------------------------------------------------+
| NSP      | NetScout Probe                                            |
+----------+-----------------------------------------------------------+
| NSR      | NISN Service Request                                      |
+----------+-----------------------------------------------------------+
| NSRF     | NISN Service Request Form                                 |
+----------+-----------------------------------------------------------+
| NSRS     | NISN Services Request System                              |
+----------+-----------------------------------------------------------+
| NSS      | Network Support Subsystem                                 |
|          |                                                           |
|          | Network Security Services                                 |
|          |                                                           |
|          | NASA Safety Standard                                      |
+----------+-----------------------------------------------------------+
| NSSC     | NASA Shared Services Center                               |
+----------+-----------------------------------------------------------+
| NSSTC    | National Space and Science Technology Center              |
+----------+-----------------------------------------------------------+
| NST      | Near-Simultaneous Tracking                                |
+----------+-----------------------------------------------------------+
| NSTS     | National Space Transportation System                      |
+----------+-----------------------------------------------------------+
| NT       | New Technology                                            |
+----------+-----------------------------------------------------------+
| NTC      | NASA Teleconferencing Center                              |
+----------+-----------------------------------------------------------+
| NTD      | NISN Service Request ????                                 |
+----------+-----------------------------------------------------------+
| NTFS     | New Technology File System                                |
+----------+-----------------------------------------------------------+
| NTP      | Network Time Protocol                                     |
+----------+-----------------------------------------------------------+
| NTR      | NSAP Technology Refresh                                   |
+----------+-----------------------------------------------------------+
| NTSC     | National Television Standard Code                         |
+----------+-----------------------------------------------------------+
| O&C      | Operations and Checkout                                   |
+----------+-----------------------------------------------------------+
| O&I      | Operations and Integration                                |
+----------+-----------------------------------------------------------+
| O&M      | Operations and Maintenance                                |
+----------+-----------------------------------------------------------+
| O/A      | Optimized Access                                          |
+----------+-----------------------------------------------------------+
| OAB      | Off-line Address Book                                     |
+----------+-----------------------------------------------------------+
| OAFB     | Onizuka Air Force Base                                    |
+----------+-----------------------------------------------------------+
| OAO      | Orbiting Astronomical Observatory                         |
+----------+-----------------------------------------------------------+
| OARE     | Orbital Acceleration Research Experiment                  |
+----------+-----------------------------------------------------------+
| OARNET   | Ohio Academic and Research Network                        |
+----------+-----------------------------------------------------------+
| OAS      | Operation and Support                                     |
|          |                                                           |
|          | Onizuka Air Station                                       |
+----------+-----------------------------------------------------------+
| OBS      | Organizational Breakdown Structure                        |
+----------+-----------------------------------------------------------+
| OC       | Optical Carrier (OC-3)                                    |
+----------+-----------------------------------------------------------+
| OCA      | Orbital Communications Adapter                            |
+----------+-----------------------------------------------------------+
| OCC      | Operations Control Center                                 |
+----------+-----------------------------------------------------------+
| OCO      | Orbiting Carbon Observatory                               |
+----------+-----------------------------------------------------------+
| OCU      | Office Channel Unit                                       |
+----------+-----------------------------------------------------------+
| OD       | Orbiter Downlink                                          |
|          |                                                           |
|          | Orbit Determination                                       |
|          |                                                           |
|          | Operations Downlink                                       |
+----------+-----------------------------------------------------------+
| ODBC     | Open Data Base Connectivity                               |
+----------+-----------------------------------------------------------+
| ODC      | Other Direct Costs                                        |
+----------+-----------------------------------------------------------+
| ODIN     | Outsourcing Desktop Initiative for NASA                   |
+----------+-----------------------------------------------------------+
| ODM      | Operational Data Message                                  |
+----------+-----------------------------------------------------------+
| ODM      | Operational Directive Memorandum                          |
+----------+-----------------------------------------------------------+
| ODRC     | Operational Data Reduction Complex                        |
+----------+-----------------------------------------------------------+
| OI       | Operational Instrumentation                               |
|          |                                                           |
|          | Orbital Interface                                         |
+----------+-----------------------------------------------------------+
| OIG      | Office of the Inspector General                           |
+----------+-----------------------------------------------------------+
| OIRB     | Operations Incident Review Board                          |
+----------+-----------------------------------------------------------+
| OIS      | Operational Intercom System                               |
+----------+-----------------------------------------------------------+
| OLA      | Operational Level Agreement                               |
+----------+-----------------------------------------------------------+
| OMB      | Office of Management and Budget                           |
+----------+-----------------------------------------------------------+
| OND      | Operator need date                                        |
+----------+-----------------------------------------------------------+
| ONS      | Optical Network Solution                                  |
+----------+-----------------------------------------------------------+
| OOBA     | Out of Band Access                                        |
+----------+-----------------------------------------------------------+
| OOTF     | Office of the Future                                      |
+----------+-----------------------------------------------------------+
| OPR      | Officer of Primary Responsibility                         |
+----------+-----------------------------------------------------------+
| OPS      | Operations                                                |
+----------+-----------------------------------------------------------+
| OPUS     | Open Source Unix Software                                 |
+----------+-----------------------------------------------------------+
| ORD      | Organization Responsibility Document                      |
+----------+-----------------------------------------------------------+
| ORR      | Operational Readiness Review                              |
+----------+-----------------------------------------------------------+
| ORS      | Online Reservation System                                 |
+----------+-----------------------------------------------------------+
| ORTS     | Operations Readiness Test Set                             |
+----------+-----------------------------------------------------------+
| OS       | Operating System                                          |
+----------+-----------------------------------------------------------+
| OSB      | Operations Support Building                               |
+----------+-----------------------------------------------------------+
| OSC      | Orbital Sciences Corporation                              |
+----------+-----------------------------------------------------------+
| OSF      | Office of Space Flight                                    |
+----------+-----------------------------------------------------------+
| OSHA     | Occupational Safety & Health Agency                       |
+----------+-----------------------------------------------------------+
| OSP      | Orbital-Suborbital Program                                |
+----------+-----------------------------------------------------------+
| OSPF     | Open Shortest Path First                                  |
+----------+-----------------------------------------------------------+
| OST      | Operations Support Team                                   |
+----------+-----------------------------------------------------------+
| OSTPV    | On-Station Procedure Viewer                               |
+----------+-----------------------------------------------------------+
| OTS      | Organization Tracking System                              |
+----------+-----------------------------------------------------------+
| P2P      | Peer to Peer                                              |
+----------+-----------------------------------------------------------+
| PACOR    | Packet Processor                                          |
+----------+-----------------------------------------------------------+
| PAIX     | Palo Alto Internet Exchange                               |
+----------+-----------------------------------------------------------+
| PALS     | Program Automated Library System                          |
+----------+-----------------------------------------------------------+
| PAO      | Public Affairs Office                                     |
+----------+-----------------------------------------------------------+
| PAR      | Pre-Launch Assessment Review                              |
+----------+-----------------------------------------------------------+
| PBERT    | Packet Bit Error Rate Tester                              |
+----------+-----------------------------------------------------------+
| PBX      | Private Branch Exchange                                   |
+----------+-----------------------------------------------------------+
| PCB      | Process Control Board                                     |
|          |                                                           |
|          | Program Control Board                                     |
+----------+-----------------------------------------------------------+
| PCCW     | Hong Kong Telecommunications Research                     |
+----------+-----------------------------------------------------------+
| PCD      | Project Commitment Document                               |
+----------+-----------------------------------------------------------+
| PCM      | Pulse Code Modulation                                     |
+----------+-----------------------------------------------------------+
| PCR      | Post Completion Review                                    |
+----------+-----------------------------------------------------------+
| PDARS    | Performance Data Analysis Reporting System                |
+----------+-----------------------------------------------------------+
| PDF      | Portable Document File/Format                             |
+----------+-----------------------------------------------------------+
| PDI      | Payload Data Interleave                                   |
+----------+-----------------------------------------------------------+
| PDL      | Procedure Distribution List                               |
|          |                                                           |
|          | Program Design Language                                   |
|          |                                                           |
|          | Ponce De Leon                                             |
+----------+-----------------------------------------------------------+
| PDR      | Preliminary Design Review                                 |
+----------+-----------------------------------------------------------+
| PDSS     | Payload Data Services System                              |
+----------+-----------------------------------------------------------+
| PE       | Program Executive                                         |
+----------+-----------------------------------------------------------+
| PEB      | Performance Evaluation Board                              |
+----------+-----------------------------------------------------------+
| PEI      | Products and Engineering with Innovation, Electronics     |
|          | Incorporated                                              |
+----------+-----------------------------------------------------------+
| PEM      | Patrol Enterprise Management                              |
+----------+-----------------------------------------------------------+
| PFC      | Policy Feature Card                                       |
+----------+-----------------------------------------------------------+
| PFLT     | Poker Flats                                               |
+----------+-----------------------------------------------------------+
| PFRR     | Poker Flat Research Range                                 |
+----------+-----------------------------------------------------------+
| PFS      | Poker Flat Station                                        |
+----------+-----------------------------------------------------------+
| PGP      | Pretty Good Privacy                                       |
+----------+-----------------------------------------------------------+
| PI       | Principle Investigator                                    |
+----------+-----------------------------------------------------------+
| PIC      | Primary Inter-Exchange Carrier                            |
|          |                                                           |
|          | Project Information Center                                |
+----------+-----------------------------------------------------------+
| PIDs     | Parameter Identifiers                                     |
+----------+-----------------------------------------------------------+
| PIMMS    | Private Investigator Microgravity Management Systems      |
+----------+-----------------------------------------------------------+
| PIO      | Program Integration Office                                |
+----------+-----------------------------------------------------------+
| PIP      | Premium Internet Protocol                                 |
|          |                                                           |
|          | Payload Integration Plan                                  |
+----------+-----------------------------------------------------------+
| PIX      | Private Internet Exchange                                 |
+----------+-----------------------------------------------------------+
| PKI      | Public Key Infrastructure                                 |
+----------+-----------------------------------------------------------+
| PM       | Preventative Maintenance                                  |
|          |                                                           |
|          | Program Manager                                           |
+----------+-----------------------------------------------------------+
| PMB      | Program Management Budget                                 |
+----------+-----------------------------------------------------------+
| PMDS     | Problem Management Dispatch System                        |
+----------+-----------------------------------------------------------+
| PMM      | Program Management Metrics                                |
+----------+-----------------------------------------------------------+
| PMR      | Program Management Review                                 |
+----------+-----------------------------------------------------------+
| PMS      | Performance Measuring System                              |
+----------+-----------------------------------------------------------+
| PMSR     | Performance Measurement Status Report                     |
+----------+-----------------------------------------------------------+
| PNOPS    | PrISMS Network Operations                                 |
+----------+-----------------------------------------------------------+
| PO       | Project Office                                            |
|          |                                                           |
|          | Purchase Order                                            |
+----------+-----------------------------------------------------------+
| PO.DACC  | Physical Oceanography Distributed Active Archive Center   |
+----------+-----------------------------------------------------------+
| POC      | Point of Contact                                          |
|          |                                                           |
|          | Project Operations Center                                 |
+----------+-----------------------------------------------------------+
| POCC     | Payload Operations Control Center                         |
+----------+-----------------------------------------------------------+
| POES     | # Polar Operational Environmental Satellite               |
+----------+-----------------------------------------------------------+
| POGO     | # Polar Orbiting Geophysical Observatory                  |
+----------+-----------------------------------------------------------+
| POIC     | Payload Operations Integration Center                     |
+----------+-----------------------------------------------------------+
| POLAR    | Polar Plasma Laboratory                                   |
+----------+-----------------------------------------------------------+
| POP      | Program Operating Plan                                    |
+----------+-----------------------------------------------------------+
| PoP      | Point of Presence                                         |
+----------+-----------------------------------------------------------+
| POS      | Packet Over SONET                                         |
+----------+-----------------------------------------------------------+
| POTS     | Plain Old Telephone Service                               |
+----------+-----------------------------------------------------------+
| POW      | Plumbrook Ordinance Works                                 |
+----------+-----------------------------------------------------------+
| PP&C     | Project Planning and Control                              |
+----------+-----------------------------------------------------------+
| PPOV     | Pilot Point of View                                       |
+----------+-----------------------------------------------------------+
| PPP      | Point-to-Point Protocol                                   |
+----------+-----------------------------------------------------------+
| PPS      | Peripheral Processing System                              |
|          |                                                           |
|          | Pneumatic Power Subsystem                                 |
|          |                                                           |
|          | Printer/Plotter System                                    |
|          |                                                           |
|          | Proposal Pricing System                                   |
|          |                                                           |
|          | Provisioning Performance Schedule                         |
|          |                                                           |
|          | Pulse Per Second                                          |
|          |                                                           |
|          | Payload Pointing System                                   |
+----------+-----------------------------------------------------------+
| PR       | Purchase Request                                          |
+----------+-----------------------------------------------------------+
| PRC      | Program Review Center                                     |
+----------+-----------------------------------------------------------+
| PRD      | Program Requirements Document                             |
+----------+-----------------------------------------------------------+
| PRI      | Primary Rate Interface                                    |
+----------+-----------------------------------------------------------+
| PrISMS   | Program Information Systems Mission Services              |
+----------+-----------------------------------------------------------+
| PRNG     | Pseudo Random Number Generator                            |
+----------+-----------------------------------------------------------+
| ProSEDS  | Propulsive Small Expendable Deployer System               |
+----------+-----------------------------------------------------------+
| PRS      | Primary Reference Source                                  |
+----------+-----------------------------------------------------------+
| PS       | Photopolarimeter Subsystem                                |
|          |                                                           |
|          | Power Supply                                              |
+----------+-----------------------------------------------------------+
| PSAM     | Preliminary Service Advisory Message                      |
+----------+-----------------------------------------------------------+
| PSC      | Project Steering Committee                                |
+----------+-----------------------------------------------------------+
| PSCNI    | Program Support Communications Network/Interface          |
+----------+-----------------------------------------------------------+
| PSD      | Power Spectral Density                                    |
+----------+-----------------------------------------------------------+
| PSLA     | Program Service Level Agreement                           |
+----------+-----------------------------------------------------------+
| PSR      | Program Status Review                                     |
+----------+-----------------------------------------------------------+
| PSTN     | Public Switched Telephone Network                         |
+----------+-----------------------------------------------------------+
| PSU      | Pennsylvania State University                             |
+----------+-----------------------------------------------------------+
| PTCS     | Payload Test and Checkout System                          |
+----------+-----------------------------------------------------------+
| PTD      | Propulsion Test Directorate                               |
+----------+-----------------------------------------------------------+
| PTP      | Programmable Telemetry Processor                          |
+----------+-----------------------------------------------------------+
| PUB      | Public Access                                             |
+----------+-----------------------------------------------------------+
| PVC      | Permanent Virtual Circuit                                 |
+----------+-----------------------------------------------------------+
| PWC      | Price Waterhouse Cooper                                   |
+----------+-----------------------------------------------------------+
| PWS      | Performance Work Statement                                |
+----------+-----------------------------------------------------------+
| Q&A      | # Question and Answer                                     |
+----------+-----------------------------------------------------------+
| QA       | Quality Assurance                                         |
+----------+-----------------------------------------------------------+
| QBRI     | # Quad Basic Rate Interface                               |
+----------+-----------------------------------------------------------+
| QFS      | # Quick File System                                       |
+----------+-----------------------------------------------------------+
| QoS      | # Quality of Service                                      |
+----------+-----------------------------------------------------------+
| QUESTeam | # Quality Efficient Services Team                         |
+----------+-----------------------------------------------------------+
| Q        | # Quick Scatterometer                                     |
| uickSCAT |                                                           |
+----------+-----------------------------------------------------------+
| R&D      | # Research and Development                                |
+----------+-----------------------------------------------------------+
| R&R      | # Requirements and Response                               |
+----------+-----------------------------------------------------------+
| r/pm     | #                                                         |
|          |  Revolutions Per Minute (RPM, rpm, but preferred is r/pm) |
+----------+-----------------------------------------------------------+
| RA       | Risk Assessment                                           |
+----------+-----------------------------------------------------------+
| RAC      | Remote Access Console                                     |
+----------+-----------------------------------------------------------+
| RADIUS   | Remote Authentication Dial-In User Service                |
+----------+-----------------------------------------------------------+
| RAID     | Redundant Array of Inexpensive Disks                      |
+----------+-----------------------------------------------------------+
| RAM      | Random Access Memory                                      |
+----------+-----------------------------------------------------------+
| RC       | Recovery Controller                                       |
+----------+-----------------------------------------------------------+
| RCA      | Root Cause Analysis                                       |
+----------+-----------------------------------------------------------+
| RCCA     | Root Cause and Corrective Action                          |
+----------+-----------------------------------------------------------+
| RCIP     | Real-time Critical Internet Protocol                      |
+----------+-----------------------------------------------------------+
| RCN      | Regional Communications Network                           |
+----------+-----------------------------------------------------------+
| RD       | Requirements Document                                     |
+----------+-----------------------------------------------------------+
| RDAC     | Redundant Disk Array Controller                           |
+----------+-----------------------------------------------------------+
| RDD      | Release Description Document                              |
+----------+-----------------------------------------------------------+
| RDIR     | Routed Data Infrastructure Refresh                        |
+----------+-----------------------------------------------------------+
| RECP     | Request for Engineering Change Proposal                   |
+----------+-----------------------------------------------------------+
| REIF     | Redundant Equipment Interface                             |
+----------+-----------------------------------------------------------+
| REOC     | Redundant EOS Operations Center                           |
|          |                                                           |
|          | Remote Earth Operations Center                            |
+----------+-----------------------------------------------------------+
| RESE     | Canadian Reseau d'Evaluation et de Surveillance           |
|          | Ecologiques or Canadian Ecological Monitoring and         |
|          | Assessment Network                                        |
+----------+-----------------------------------------------------------+
| RF       | Radio Frequency                                           |
+----------+-----------------------------------------------------------+
| RFC      | Request for Comment                                       |
+----------+-----------------------------------------------------------+
| RFI      | Radio Frequency Interference                              |
|          |                                                           |
|          | Request for Information                                   |
+----------+-----------------------------------------------------------+
| RFO      | Request For Offer                                         |
+----------+-----------------------------------------------------------+
| RFP      | Request For Proposal                                      |
+----------+-----------------------------------------------------------+
| RFQ      | Request for Quote                                         |
+----------+-----------------------------------------------------------+
| RFSOC    | Radio Frequency Simulations Operations Center             |
+----------+-----------------------------------------------------------+
| RGB      | Red, Green, Blue                                          |
+----------+-----------------------------------------------------------+
| RID      | Review Item Discrepancy/Disposition                       |
+----------+-----------------------------------------------------------+
| RIF      | Reduction In Force                                        |
+----------+-----------------------------------------------------------+
| RIOnet   | Restricted IOnet                                          |
+----------+-----------------------------------------------------------+
| RIPE     | Reseaux Internet Protocol Europeans (Francais)            |
+----------+-----------------------------------------------------------+
| RIR      | Requirements Impact Report                                |
+----------+-----------------------------------------------------------+
| RJ       | Registered Jack                                           |
+----------+-----------------------------------------------------------+
| RLZP     | Re-engineering Level Zero Processor                       |
+----------+-----------------------------------------------------------+
| RMA      | Return Material Authorization                             |
+----------+-----------------------------------------------------------+
| RMON     | Remote Monitor                                            |
+----------+-----------------------------------------------------------+
| RNET     | Type of Network                                           |
+----------+-----------------------------------------------------------+
| ROCS     | Router Configuration Server                               |
|          |                                                           |
| ROM      | Rough Order of Magnitude                                  |
+----------+-----------------------------------------------------------+
| ROS      | Russian Orbital Segment                                   |
|          |                                                           |
|          | Remote Operational System                                 |
+----------+-----------------------------------------------------------+
| R        | Russia Federal Space Agency                               |
| oscosmos |                                                           |
+----------+-----------------------------------------------------------+
| RPC      | Remote Procedure Call                                     |
+----------+-----------------------------------------------------------+
| RPCSS    | Remote Procedure Call Security Services                   |
+----------+-----------------------------------------------------------+
| RPI      | Remote Principal Investigator                             |
+----------+-----------------------------------------------------------+
| RPR      | Resilient Packet Ring                                     |
+----------+-----------------------------------------------------------+
| RPS      | Remote Playback System                                    |
|          |                                                           |
|          | Record Playback Subsystem                                 |
|          |                                                           |
|          | Raytheon Polar Services                                   |
+----------+-----------------------------------------------------------+
| RPSC     | Raytheon Polar Services Company                           |
+----------+-----------------------------------------------------------+
| RS       | Recommended Standard                                      |
+----------+-----------------------------------------------------------+
| RSA      | Russian Space Agency                                      |
+----------+-----------------------------------------------------------+
| RSC-E    | Rocket Space Corporation-Energia                          |
+----------+-----------------------------------------------------------+
| RSP      | Route Switch Processor                                    |
+----------+-----------------------------------------------------------+
| RSRM     | Redesigned Solid Rocket Motor                             |
+----------+-----------------------------------------------------------+
| RSVG     | Russia Services Group                                     |
+----------+-----------------------------------------------------------+
| RSVP     | Respondez s'il vous plait (please reply)                  |
+----------+-----------------------------------------------------------+
| RT       | Real-Time                                                 |
+----------+-----------------------------------------------------------+
| RTCH     | Research and Technology                                   |
+----------+-----------------------------------------------------------+
| RTF      | Return to Flight                                          |
+----------+-----------------------------------------------------------+
| RTOD     | Real-Time Orbital Determination                           |
+----------+-----------------------------------------------------------+
| RTT      | Round Trip Time                                           |
+----------+-----------------------------------------------------------+
| RXTE     | Rossi X-Ray Timing Explorer                               |
+----------+-----------------------------------------------------------+
| S/C      | Spacecraft                                                |
+----------+-----------------------------------------------------------+
| S/W or   | Software                                                  |
| SW       |                                                           |
+----------+-----------------------------------------------------------+
| SA       | Service Agreement                                         |
+----------+-----------------------------------------------------------+
| SAC      | Scientific Applications Satellite                         |
+----------+-----------------------------------------------------------+
| SAFB     | Schriever Air Force Base                                  |
+----------+-----------------------------------------------------------+
| SAGE     | Instrument on ERBS Satellite                              |
+----------+-----------------------------------------------------------+
| SAIC     | Science Applications International Corporation            |
+----------+-----------------------------------------------------------+
| SAIL     | Shuttle Avionics Integration Laboratory                   |
+----------+-----------------------------------------------------------+
| SAMPEX   | Solar Anomalous and Magnetosphere Particle Explorer       |
+----------+-----------------------------------------------------------+
| SAN      | Storage Area Network                                      |
+----------+-----------------------------------------------------------+
| SANCP    | Security Analyst Network Connection Profiler              |
+----------+-----------------------------------------------------------+
| SA       | A storage manager                                         |
| Ntricity |                                                           |
+----------+-----------------------------------------------------------+
| SAO      | Smithsonian Astrophysical Observatory                     |
+----------+-----------------------------------------------------------+
| SAP      | Software Brand Name                                       |
+----------+-----------------------------------------------------------+
| SAR      | Synthetic Aperture Radar                                  |
+----------+-----------------------------------------------------------+
| SAR      | System Acceptance Review                                  |
+----------+-----------------------------------------------------------+
| SART     | Security Analysis and Response Team                       |
+----------+-----------------------------------------------------------+
| SAT      | System Acceptance Testing                                 |
+----------+-----------------------------------------------------------+
| SATS     | System Acceptance Test Sets                               |
+----------+-----------------------------------------------------------+
| SB       | Small Business                                            |
+----------+-----------------------------------------------------------+
| SBC      | In                                                        |
|          | [1998](http://www.answers.com/main/nt                     |
|          | query?method=4&dsid=2222&dekey=1998&gwp=8&curtab=2222_1), |
|          | Southwestern Bell changed its name to SBC Communications. |
|          | The company has stated that *SBC* no longer stands for    |
|          | anything.                                                 |
+----------+-----------------------------------------------------------+
| SBRY     | Southbury, CT                                             |
+----------+-----------------------------------------------------------+
| SC       | Stick & Click Connector                                   |
+----------+-----------------------------------------------------------+
| SCAMA    | Switching Conference and Monitoring Arrangement           |
+----------+-----------------------------------------------------------+
| SCAWG    | Space Communications Architecture Working Group           |
+----------+-----------------------------------------------------------+
| SCD      | Small Conversion Device                                   |
+----------+-----------------------------------------------------------+
| SCDS     | Space Communications and Data Systems (was SOMO)          |
+----------+-----------------------------------------------------------+
| SCIO     | Space Communications Integration Office                   |
+----------+-----------------------------------------------------------+
| SCR      | Security Controls Review                                  |
+----------+-----------------------------------------------------------+
| SCSI     | Small Computer System Interface                           |
+----------+-----------------------------------------------------------+
| SD       | Service Delivery                                          |
+----------+-----------------------------------------------------------+
| SDB      | Small Disadvantage Business                               |
+----------+-----------------------------------------------------------+
| SDF      | Software Development Facility/File                        |
+----------+-----------------------------------------------------------+
| SDI      | Serial Digital Interface                                  |
+----------+-----------------------------------------------------------+
| SDIL     | Software Development Integration Laboratory               |
+----------+-----------------------------------------------------------+
| SDLC     | System Development Lifecycle                              |
+----------+-----------------------------------------------------------+
| SDO      | Solar Dynamics Observatory                                |
+----------+-----------------------------------------------------------+
| SDR      | System Design Review                                      |
+----------+-----------------------------------------------------------+
| SDRAM    | Synchronous Dynamic Random Access Memory                  |
+----------+-----------------------------------------------------------+
| SDRD     | Subcontractor Data Report Delivery                        |
+----------+-----------------------------------------------------------+
| SDS      | Shuttle Data Stream                                       |
+----------+-----------------------------------------------------------+
| SEAPAC   | Sea Winds Processing and Analysis Center                  |
+----------+-----------------------------------------------------------+
| SEB      | Source Evaluation Board                                   |
+----------+-----------------------------------------------------------+
| SECR     | Shuttle Engineering Console Room                          |
+----------+-----------------------------------------------------------+
| SEF      | Sustaining Engineering Facility                           |
+----------+-----------------------------------------------------------+
| SER      | Scientific, Engineering, and Research                     |
+----------+-----------------------------------------------------------+
| SERB     | Systems Engineering Review Board                          |
+----------+-----------------------------------------------------------+
| SERPL    | Space Experiment Research and Processing Laboratory       |
+----------+-----------------------------------------------------------+
| SET      | System Engineering Team                                   |
+----------+-----------------------------------------------------------+
| SEWG     | Systems Engineering Working Group                         |
+----------+-----------------------------------------------------------+
| SEWP     | Scientific and Engineering Workstation Procurement        |
+----------+-----------------------------------------------------------+
| SFAL     | Sioux Falls, (site of EROS Data Center)                   |
+----------+-----------------------------------------------------------+
| SFG      | Special Function Gateway                                  |
+----------+-----------------------------------------------------------+
| SFOC     | Space Flight Operations Contract                          |
+----------+-----------------------------------------------------------+
| SGI      | Silicon Graphics Incorporated                             |
+----------+-----------------------------------------------------------+
| SGLT     | Space Ground Local Terminal                               |
+----------+-----------------------------------------------------------+
| SGS      | Svalbard Ground Station                                   |
|          |                                                           |
|          | Space-to-Ground System                                    |
+----------+-----------------------------------------------------------+
| SHARAD   | Shallow Radar                                             |
+----------+-----------------------------------------------------------+
| SHE      | Safety, Health, and Environmental                         |
+----------+-----------------------------------------------------------+
| SIMMS    | Scalable Integrated, Multi-mission Simulation Suite       |
+----------+-----------------------------------------------------------+
| SINET    | Science Information Network                               |
+----------+-----------------------------------------------------------+
| SIO      | Systems Integration Office                                |
+----------+-----------------------------------------------------------+
| SIP      | Session Initiation Protocol                               |
+----------+-----------------------------------------------------------+
| SIP      | Standard Internet Protocol                                |
+----------+-----------------------------------------------------------+
| SIRIUS   | Spacecraft                                                |
+----------+-----------------------------------------------------------+
| SIRTE    | Space Infrared Telescope Facility                         |
+----------+-----------------------------------------------------------+
| SIT      | Service Improvement Team                                  |
|          |                                                           |
|          | Shuttle Interface Test                                    |
+----------+-----------------------------------------------------------+
| SLA      | Service Level Agreement                                   |
+----------+-----------------------------------------------------------+
| SLE      | Space Link Extension                                      |
+----------+-----------------------------------------------------------+
| SLOC     | Single Line of Code                                       |
+----------+-----------------------------------------------------------+
| SM       | Subsystem Manager                                         |
|          |                                                           |
|          | Stat Mux (as in SM-1 or SM-2)                             |
|          |                                                           |
|          | Service Manager                                           |
+----------+-----------------------------------------------------------+
| SMA      | Special Management Attention                              |
|          |                                                           |
|          | Science Monitoring Area                                   |
+----------+-----------------------------------------------------------+
| SMB      | Server Message Blocks                                     |
+----------+-----------------------------------------------------------+
| SMDS     | Switched Multi-megabit Data Service                       |
+----------+-----------------------------------------------------------+
| SME      | Subject Matter Experts                                    |
+----------+-----------------------------------------------------------+
| SMIS     | Shuttle Mission Imaging System                            |
+----------+-----------------------------------------------------------+
| SMP      | System Management Policy                                  |
+----------+-----------------------------------------------------------+
| SMTP     | Simple Mail Transport Protocol                            |
+----------+-----------------------------------------------------------+
| SN       | Space Network                                             |
+----------+-----------------------------------------------------------+
| SN/GN    | Space Network/Ground Network                              |
+----------+-----------------------------------------------------------+
| SNA      | System Network Architecture                               |
+----------+-----------------------------------------------------------+
| SNMP     | Simple Network Management Protocol                        |
+----------+-----------------------------------------------------------+
| SNOE     | Student Nitric Oxide Explorer                             |
+----------+-----------------------------------------------------------+
| SO       | Support Operations                                        |
|          |                                                           |
|          | Service Order                                             |
+----------+-----------------------------------------------------------+
| SOC      | Science Operations Center                                 |
+----------+-----------------------------------------------------------+
| SOC      | Space Operations Center                                   |
+----------+-----------------------------------------------------------+
| SOCB     | Space Operations Control Board                            |
+----------+-----------------------------------------------------------+
| SOCC     | Satellite Operations Control Center                       |
+----------+-----------------------------------------------------------+
| SODA     | Space Operations Directive Agreement                      |
+----------+-----------------------------------------------------------+
| SOE      | Standard of Excellence                                    |
+----------+-----------------------------------------------------------+
| SOFBALL  | Structure of Flame Balls at Low Lewis                     |
+----------+-----------------------------------------------------------+
| SOFIA    | Stratospheric Observatory for Infrared Astronomy          |
+----------+-----------------------------------------------------------+
| SOHO     | Solar and Heliosperic Observatory                         |
+----------+-----------------------------------------------------------+
| SOLAR    | Site for On0Line Learning and Resources                   |
+----------+-----------------------------------------------------------+
| SOMD     | Space Operations Mission Directorate                      |
+----------+-----------------------------------------------------------+
| SOMO     | Space Operations Management Office **(changed to SCDS)**  |
+----------+-----------------------------------------------------------+
| SONET    | Synchronous Optical Network                               |
+----------+-----------------------------------------------------------+
| SOP      | Standard Operating Procedure                              |
+----------+-----------------------------------------------------------+
| SORCE    | Solar Radiation and Climate Explorer                      |
+----------+-----------------------------------------------------------+
| SOW      | Statement of Work                                         |
+----------+-----------------------------------------------------------+
| SP       | South Pole                                                |
+----------+-----------------------------------------------------------+
| SP       | Superior Performance                                      |
+----------+-----------------------------------------------------------+
| SPAWAR   | Naval Space Warfare Systems Center                        |
+----------+-----------------------------------------------------------+
| SPIF     | Shuttle Payload Interface Facility                        |
+----------+-----------------------------------------------------------+
| SPM      | Service Performance Metrics                               |
+----------+-----------------------------------------------------------+
| SPMS     | Security Patrol Management System                         |
+----------+-----------------------------------------------------------+
| SPOC     | Single Point of Contact                                   |
+----------+-----------------------------------------------------------+
| SPP      | Support Products Provider                                 |
+----------+-----------------------------------------------------------+
| SPPA     | Support Products Provider Assembly                        |
+----------+-----------------------------------------------------------+
| SQL      | Structured Query Language                                 |
+----------+-----------------------------------------------------------+
| SR       | Service Request                                           |
+----------+-----------------------------------------------------------+
| SR&QA    | Safety, Reliability and Quality Assurance                 |
+----------+-----------------------------------------------------------+
| SR&QA    | Safety, Reliability and Quality Assurance                 |
+----------+-----------------------------------------------------------+
| SRA      | Sequential Ranging Assembly                               |
+----------+-----------------------------------------------------------+
| SRB      | Solid Rocket Booster                                      |
+----------+-----------------------------------------------------------+
| SRM      | Service Reference Model                                   |
+----------+-----------------------------------------------------------+
| SRR      | Strategic Resource Review                                 |
+----------+-----------------------------------------------------------+
| SRS      | Service Request System                                    |
+----------+-----------------------------------------------------------+
| SRTM     | Shuttle Radar Topography Mission                          |
+----------+-----------------------------------------------------------+
| SSA      | Single Service Access                                     |
+----------+-----------------------------------------------------------+
| SSC      | Stennis Space Center                                      |
|          |                                                           |
|          | Space Station Complex                                     |
|          |                                                           |
|          | Site Security Coordinator                                 |
+----------+-----------------------------------------------------------+
| SSCI     | Stennis Space Center -- Institutional.                    |
+----------+-----------------------------------------------------------+
| SSE      | Solar System Exploration                                  |
+----------+-----------------------------------------------------------+
| SSEO     | Space Science and Earth Observation                       |
+----------+-----------------------------------------------------------+
| SSFDR    | Subsystem Functional Design Review                        |
+----------+-----------------------------------------------------------+
| SSH      | Security Shell                                            |
+----------+-----------------------------------------------------------+
| SSL      | Secure Socket Layer                                       |
+----------+-----------------------------------------------------------+
| SSM      | Site Status Message                                       |
|          |                                                           |
|          | Source Specific Multicast                                 |
+----------+-----------------------------------------------------------+
| SSME     | Space Shuttle Main Engine                                 |
+----------+-----------------------------------------------------------+
| SSP      | Support Products Provider                                 |
+----------+-----------------------------------------------------------+
| SSPA     | SSP Assembly                                              |
+----------+-----------------------------------------------------------+
| SSPP     | System Safety Program Plan                                |
+----------+-----------------------------------------------------------+
| SSPRO    | Space Shuttle Program Resident Office                     |
+----------+-----------------------------------------------------------+
| SSSOT    | SOMO Standard Services Ordering Tool                      |
+----------+-----------------------------------------------------------+
| ST       | System Test                                               |
|          |                                                           |
|          | Stick and Twist Connector                                 |
|          |                                                           |
|          | Space Technology (as in ST-5)                             |
+----------+-----------------------------------------------------------+
| STA      | Shuttle Trainer Aircraft                                  |
+----------+-----------------------------------------------------------+
| STADIR   | Station Director (NASA)                                   |
+----------+-----------------------------------------------------------+
| STAN     | Stanford University                                       |
+----------+-----------------------------------------------------------+
| STAR     | System Trades and Risks                                   |
+----------+-----------------------------------------------------------+
| S        | Name of Mission                                           |
| tarLight |                                                           |
+----------+-----------------------------------------------------------+
| STARS    | Space Based Telemetry and Range Safety                    |
+----------+-----------------------------------------------------------+
| STARTAP  | Science, Technology, And Research Transit Access Point    |
+----------+-----------------------------------------------------------+
| STAT MUX | Statistical Multiplexer                                   |
+----------+-----------------------------------------------------------+
| STDN     | Spaceflight Tracking Data Network                         |
+----------+-----------------------------------------------------------+
| STEREO   | Solar Terrestrial Event Observer                          |
+----------+-----------------------------------------------------------+
| STGT     | Second TDRSS Ground Terminal                              |
+----------+-----------------------------------------------------------+
| STK      | StorageTek                                                |
+----------+-----------------------------------------------------------+
| STOCC    | Space Telescope Operations Control Center                 |
+----------+-----------------------------------------------------------+
| STPS     | Shuttle Telemetry Processing System                       |
+----------+-----------------------------------------------------------+
| STR      | System Test Review                                        |
+----------+-----------------------------------------------------------+
| STS      | Space Transportation System                               |
+----------+-----------------------------------------------------------+
| STSI     | Space Telescope Science Institute                         |
+----------+-----------------------------------------------------------+
| STX      | Science and Technology Excellence                         |
+----------+-----------------------------------------------------------+
| SUIT     | Suitland, Maryland                                        |
+----------+-----------------------------------------------------------+
| SV       | Schedule Variance                                         |
+----------+-----------------------------------------------------------+
| SVEL     | Service Element                                           |
+----------+-----------------------------------------------------------+
| SVF      | Shuttle Verification Facility                             |
+----------+-----------------------------------------------------------+
| SVS      | Switched Voice Service                                    |
+----------+-----------------------------------------------------------+
| SW       | Switch                                                    |
+----------+-----------------------------------------------------------+
| SW or    | Software                                                  |
| S/W      |                                                           |
+----------+-----------------------------------------------------------+
| SWAS     | Submillimeter Wave Astronomy Satellite                    |
+----------+-----------------------------------------------------------+
| Swift    | (Project name -- not an acronym)                          |
+----------+-----------------------------------------------------------+
| SWO      | Security Watch Officer                                    |
+----------+-----------------------------------------------------------+
| SWON     | Switched ON (service)                                     |
+----------+-----------------------------------------------------------+
| SWSI     | Space Network Web Services Interface                      |
+----------+-----------------------------------------------------------+
| SXI      | Solar X-ray Imager                                        |
+----------+-----------------------------------------------------------+
| TABES    | Technical and Business Engineering Society                |
+----------+-----------------------------------------------------------+
| TAC      | Technical Assistance Center                               |
+----------+-----------------------------------------------------------+
| TACACS+  | Terminal Access Controller Access Control System          |
+----------+-----------------------------------------------------------+
| TAR      | Travel Authorization Request                              |
+----------+-----------------------------------------------------------+
| TB       | Tera Byte                                                 |
+----------+-----------------------------------------------------------+
| TBD      | To Be Determined                                          |
+----------+-----------------------------------------------------------+
| TBps     | Tera-Bits per second                                      |
+----------+-----------------------------------------------------------+
| TBS      | To Be Supplied                                            |
+----------+-----------------------------------------------------------+
| TCDT     | Terminal Countdown Demonstration Test                     |
+----------+-----------------------------------------------------------+
| TCID     | Test Configuration Identification Document                |
+----------+-----------------------------------------------------------+
| TCIR     | Total Case Incidence Rate                                 |
+----------+-----------------------------------------------------------+
| TCP/IP   | Transmission Control Protocol/Internet Protocol           |
+----------+-----------------------------------------------------------+
| TCX      | (Name of Company, TCX Communications -- not an acronym)   |
+----------+-----------------------------------------------------------+
| TD       | Technical Director                                        |
+----------+-----------------------------------------------------------+
| TD       | Treasury Department                                       |
+----------+-----------------------------------------------------------+
| TDA&C    | Telemetry, Data, Acquisition, and Command                 |
+----------+-----------------------------------------------------------+
| TDM      | Time Division Multiplexing                                |
+----------+-----------------------------------------------------------+
| TDRS     | Tracking Data Relay Satellite                             |
+----------+-----------------------------------------------------------+
| TDRS-E   | Tracking Data Relay Satellite, East                       |
+----------+-----------------------------------------------------------+
| TDRSS    | Tracking and Data Relay Satellite System                  |
+----------+-----------------------------------------------------------+
| TDS      | Tracking Data System                                      |
+----------+-----------------------------------------------------------+
| TEAC     | Brand Name                                                |
+----------+-----------------------------------------------------------+
| Terra    | Name of EOS spacecraft                                    |
+----------+-----------------------------------------------------------+
| TES      | Tessada - JIMMS prime contractor                          |
+----------+-----------------------------------------------------------+
| TFE      | Telemetry Front End                                       |
+----------+-----------------------------------------------------------+
| TIDY     | Temporary Duty                                            |
+----------+-----------------------------------------------------------+
| TIM      | Technical Interchange Meeting                             |
+----------+-----------------------------------------------------------+
| TKCC     | TKC Communications (Name of Company)                      |
+----------+-----------------------------------------------------------+
| TLM      | Telemetry                                                 |
+----------+-----------------------------------------------------------+
| TLS      | Transparent LAN Service                                   |
+----------+-----------------------------------------------------------+
| TMOD     | Telecommunications and Mission Operations Directorate     |
+----------+-----------------------------------------------------------+
| TMR      | Technical Monitors Representative                         |
+----------+-----------------------------------------------------------+
| TNS      | Transparent Network Substrate                             |
+----------+-----------------------------------------------------------+
| TOAD     | Software editing tool                                     |
+----------+-----------------------------------------------------------+
| TOC      | The Oceanography Society                                  |
+----------+-----------------------------------------------------------+
| TOMS     | Total Ozone Mapping Spectrometer                          |
+----------+-----------------------------------------------------------+
| TOMS-EP  | Spacecraft                                                |
+----------+-----------------------------------------------------------+
| TOPEX    | The Ocean Topography Experiment                           |
+----------+-----------------------------------------------------------+
| TOS      | Task Ordering System                                      |
+----------+-----------------------------------------------------------+
| TOTS     | Transportable Orbital Tracking System                     |
+----------+-----------------------------------------------------------+
| TPM      | Technical Performance Metrics                             |
+----------+-----------------------------------------------------------+
| TPOCC    | Transportable Payload Operations Control Center           |
+----------+-----------------------------------------------------------+
| TPP      | Test Plan & Procedures                                    |
+----------+-----------------------------------------------------------+
| TRACE    | Transitional Region and Coronal Explorer                  |
+----------+-----------------------------------------------------------+
| TRAK     | Timing System Vendor                                      |
+----------+-----------------------------------------------------------+
| TRMM     | Tropical Rainfall Measuring Mission                       |
+----------+-----------------------------------------------------------+
| Troll    | Name of firewall                                          |
+----------+-----------------------------------------------------------+
| TRR      | Test Readiness Review                                     |
+----------+-----------------------------------------------------------+
| # TSC    | Telescience Support Center                                |
+----------+-----------------------------------------------------------+
| TSP      | Telecommunications Service Priority                       |
+----------+-----------------------------------------------------------+
| TT       | Trouble Ticket                                            |
+----------+-----------------------------------------------------------+
| TT&C     | Telemetry, Tracking and Command                           |
+----------+-----------------------------------------------------------+
| TTL      | Transistor-Transistor Logic                               |
|          |                                                           |
|          | Time To Live                                              |
+----------+-----------------------------------------------------------+
| TTR      | Time to Restore                                           |
+----------+-----------------------------------------------------------+
| TVC      | Thrust Vector Control                                     |
+----------+-----------------------------------------------------------+
| TW       | TerraWave                                                 |
+----------+-----------------------------------------------------------+
| TWP      | Transition Work Plan                                      |
+----------+-----------------------------------------------------------+
| TX       | Transmit                                                  |
+----------+-----------------------------------------------------------+
| UAF      | University of Alaska - Fairbanks                          |
+----------+-----------------------------------------------------------+
| UAH      | University of Alabama in Huntsville                       |
+----------+-----------------------------------------------------------+
| UARS     | Upper Atmosphere Research Satellite                       |
+----------+-----------------------------------------------------------+
| UB       | Undistributed Budget                                      |
+----------+-----------------------------------------------------------+
| UCAR     | University Corporation for Atmospheric Research           |
+----------+-----------------------------------------------------------+
| UCB      | University of California at Berkley                       |
+----------+-----------------------------------------------------------+
| UDP      | Universal Datagram Protocol                               |
+----------+-----------------------------------------------------------+
| UHF      | Ultra High Frequency                                      |
+----------+-----------------------------------------------------------+
| ULF-1    | Utilization Flight-1                                      |
+----------+-----------------------------------------------------------+
| UMCP     | University of Maryland In College Park                    |
+----------+-----------------------------------------------------------+
| UMS      | Utilization and Mission Support                           |
+----------+-----------------------------------------------------------+
| UNITeS   | Unified NASA Information Technology Services              |
+----------+-----------------------------------------------------------+
| UNO-NCAM | University of New Orleans-National Center for Advance     |
|          | Manufacturing                                             |
+----------+-----------------------------------------------------------+
| UPS      | Uninterruptible Power Supply                              |
+----------+-----------------------------------------------------------+
| URL      | Universal Resource Locator                                |
+----------+-----------------------------------------------------------+
| USA      | United Space Alliance                                     |
|          |                                                           |
|          | United States of America                                  |
+----------+-----------------------------------------------------------+
| USAF     | United States Air Force                                   |
+----------+-----------------------------------------------------------+
| USAP     | United States Antarctic Program                           |
+----------+-----------------------------------------------------------+
| USB      | Universal Serial Bus                                      |
+----------+-----------------------------------------------------------+
| USGS     | United States Geological Survey                           |
|          |                                                           |
|          | United States Ground Segment                              |
+----------+-----------------------------------------------------------+
| USM      | Unit of Service Metric                                    |
+----------+-----------------------------------------------------------+
| USN      | Universal Space Network                                   |
+----------+-----------------------------------------------------------+
| USR      | UNITeS Status Review                                      |
+----------+-----------------------------------------------------------+
| USRA     | Universities Space Research Association                   |
+----------+-----------------------------------------------------------+
| UTP      | Unshielded Twisted Pair                                   |
+----------+-----------------------------------------------------------+
| UUNET    | Internet Service Provider -- Company Name                 |
+----------+-----------------------------------------------------------+
| V&V      | Verification and Validation                               |
+----------+-----------------------------------------------------------+
| V&VF     | Verification & Validation Facility                        |
+----------+-----------------------------------------------------------+
| VAFB     | Vandenberg Air Force Base                                 |
+----------+-----------------------------------------------------------+
| VAX      | (a mainframe computer)                                    |
+----------+-----------------------------------------------------------+
| vBNS     | very high speed Backbone Network Service                  |
+----------+-----------------------------------------------------------+
| VBScript | Visual Basic Script                                       |
+----------+-----------------------------------------------------------+
| VCR      | Video Cassette Recorder                                   |
+----------+-----------------------------------------------------------+
| VCRS     | Video Conference Request System                           |
+----------+-----------------------------------------------------------+
| VDNC     | Virtual NASA Data Center                                  |
+----------+-----------------------------------------------------------+
| VDS      | Voice/Video Distribution System                           |
+----------+-----------------------------------------------------------+
| VEST     | Vehicle Electrical Systems Test                           |
+----------+-----------------------------------------------------------+
| VGD      | Video Graphics Display                                    |
+----------+-----------------------------------------------------------+
| VGW      | Video Gateway                                             |
+----------+-----------------------------------------------------------+
| ViIP     | Video Over Internet Protocol                              |
+----------+-----------------------------------------------------------+
| VIP      | Virtual Interface Processor                               |
|          |                                                           |
|          | Verification Integration Plan                             |
|          |                                                           |
|          | Versatile Interface Processor                             |
+----------+-----------------------------------------------------------+
| Vision   | Name of Project                                           |
+----------+-----------------------------------------------------------+
| ViTS     | Video Teleconferencing System                             |
+----------+-----------------------------------------------------------+
| VLAN     | Virtual Local Area Network                                |
+----------+-----------------------------------------------------------+
| VLB1     | Very Long Baseline Interferometer                         |
+----------+-----------------------------------------------------------+
| VMS      | Voice Management System                                   |
+----------+-----------------------------------------------------------+
| VoIP     | Voice Over Internet Protocol                              |
+----------+-----------------------------------------------------------+
| VoTS     | Voice Teleconferencing System                             |
+----------+-----------------------------------------------------------+
| VPN      | Virtual Private Network                                   |
+----------+-----------------------------------------------------------+
| VPP      | Voluntary Protection Program                              |
+----------+-----------------------------------------------------------+
| VR       | Virtual Reality                                           |
+----------+-----------------------------------------------------------+
| VRA      | Video Roll About (video conferencing system)              |
+----------+-----------------------------------------------------------+
| VSM      | Value Stream Mapping                                      |
|          |                                                           |
|          | Veritas Storage Migrator                                  |
+----------+-----------------------------------------------------------+
| VSS      | Voice Switching System                                    |
+----------+-----------------------------------------------------------+
| VSS      | Voice Switching System                                    |
+----------+-----------------------------------------------------------+
| VTC      | Video Teleconferencing Center                             |
+----------+-----------------------------------------------------------+
| VTCC     | Video Teleconferencing Control Center                     |
+----------+-----------------------------------------------------------+
| VVC      | Virtual ViTS Connection                                   |
+----------+-----------------------------------------------------------+
| VVE      | ViTS VoTS Engineering                                     |
+----------+-----------------------------------------------------------+
| WACO     | Waco, TX                                                  |
+----------+-----------------------------------------------------------+
| WAD      | Work Authorization Document                               |
+----------+-----------------------------------------------------------+
| WAN      | Wide Area Network                                         |
+----------+-----------------------------------------------------------+
| WANR     | Wide Area Network Replacement                             |
+----------+-----------------------------------------------------------+
| WAPE     | WAN Architecture and Project Engineering                  |
+----------+-----------------------------------------------------------+
| WARN     | Worker Adjustment and Retraining Notification             |
+----------+-----------------------------------------------------------+
| WBS      | Work Breakdown Structure                                  |
+----------+-----------------------------------------------------------+
| WCDAS    | Wallops Command Data Acquisition Station                  |
+----------+-----------------------------------------------------------+
| WDISC    | WSC Data Interface Service Capability                     |
+----------+-----------------------------------------------------------+
| WebTADS  | Web-based Time and Attendance System                      |
+----------+-----------------------------------------------------------+
| # WFF    | Wallops Flight Facility                                   |
+----------+-----------------------------------------------------------+
| WGS      | Wallops Ground Station                                    |
+----------+-----------------------------------------------------------+
| WGS      | Wideband Ground System                                    |
|          |                                                           |
|          | Wallops Ground Station                                    |
+----------+-----------------------------------------------------------+
| WIC      | WAN Interface Card                                        |
+----------+-----------------------------------------------------------+
| WIND     | Spacecraft                                                |
+----------+-----------------------------------------------------------+
| WINS     | Windows Internet Naming Service                           |
+----------+-----------------------------------------------------------+
| WIPO     | Wind Polar Project                                        |
+----------+-----------------------------------------------------------+
| WIRE     | Wide-field Infrared Explorer                              |
+----------+-----------------------------------------------------------+
| WITS     | Washington Interagency Telecommunications System          |
+----------+-----------------------------------------------------------+
| WLPS     | Wallops Island                                            |
+----------+-----------------------------------------------------------+
| WOB      | Woman-Owned Business                                      |
+----------+-----------------------------------------------------------+
| WOITS    | Wallops Orbital Tracking Information System               |
+----------+-----------------------------------------------------------+
| WOSB     | Woman-Owned Small Business                                |
+----------+-----------------------------------------------------------+
| WPS      | Workstation Presentation Services                         |
+----------+-----------------------------------------------------------+
| WPS      | Words Per Second                                          |
|          |                                                           |
|          | Wallops                                                   |
+----------+-----------------------------------------------------------+
| WSAT     | White Sands Alternate Relay                               |
+----------+-----------------------------------------------------------+
| WSC      | White Sands Complex                                       |
+----------+-----------------------------------------------------------+
| # WSGT   | White Sands Ground Terminal                               |
+----------+-----------------------------------------------------------+
| WSMR     | White Sands Missile Range                                 |
+----------+-----------------------------------------------------------+
| WSNCC    | White Sands Network Control Center                        |
+----------+-----------------------------------------------------------+
| WSSH     | White Sands Space Harbor                                  |
+----------+-----------------------------------------------------------+
| WSTF     | White Sands Test Facility                                 |
+----------+-----------------------------------------------------------+
| WSTS     | White Sands Tracking Station                              |
+----------+-----------------------------------------------------------+
| WYE      | Work Year Equivalent                                      |
+----------+-----------------------------------------------------------+
| XO       | Company Name                                              |
+----------+-----------------------------------------------------------+
| XP       | Exchange Point                                            |
+----------+-----------------------------------------------------------+
| XSS-11   | Experimental Satellite System                             |
+----------+-----------------------------------------------------------+
| XTE      | X-Ray Timing Explorer                                     |
+----------+-----------------------------------------------------------+
| Y2K      | Year 2000                                                 |
+----------+-----------------------------------------------------------+