Exhibit 10.4.3
 
  AMENDMENT OF SOLICITATION/MODIFICATION OF CONTRACT
     (If applicable)
   (If other than Item 6)
  (No., street, county, State and Zip Code)
       (SEE ITEM 11)
  (SEE ITEM 13)
  o o o
   (If required)
         x (Specify type of modification and authority)
  x o
 (Organized by UCF section headings. including
solicitation/contract subject matter where feasible.)
     (Type or print)
  
 ( Signature of person authorized to sign)
  (Type or Print)
Anthony Wimbush
  (Signature of Contracting Officer)




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Line Item
Summary
 Document Number
 Title
 Line Item
 Number
 Description
 Delivery Date
 (Start date to End date)
 Quantity
 Unit of
 Issue
 Unit Price
 Total Cost
 Questions may be addressed to Tony Wimbush @ anthony.wimbush@fcc.gov.
  Previous Total:
 Modification Total:
 Grand Total:




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##### 



AMENDMENT OF SOLICITATION/MODIFICATION OF CONTRACT
     (if applicable)
   (if other then item 6)
  (No., street, county, State and Zip Code)
 
   (SEE ITEM 11)
  (SEE ITEM 13)
    o o o
   (if required)
     (
   (Specify type of modification and authority)
 x o
 (Organized by UCF section heading, including
solicitation/contract subject matter where feasible.)
   (Type or Print)
  (Signature of person authorized to sign)
  (Type or Print)
  /s/ Anthony Wimbush  ( Signature of Contracting Officer)




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##### 



Line Item Summary
 Document Number
 Title
 Line Item Number
 Description
 Delivery Date (Start date to End date)
 Quantity
 Unit of Issue
 Unit Price
 Total Cost
 Questions may be addressed to Tony Wimbush @ anthony.wimbush@fcc.gov.
  Previous Total:
 Modification Total:
 Grand Total:




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##### 



NANP Administration Services
 Scope of Work Change Proposal #16
 INC Issue 591: Change Timeline of Part 1 / Part 3
Processing for NANPA
  NeuStar, Inc.
    
    46000 Center Oak Plaza
Sterling, VA 20166




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Table of Contents
 1
    
    
    
    Introduction
    
    
    11.1
    
    
    
    Purpose and Scope
    
    
    11.2
    
    
    
    Modification of Guidelines
    
    
    12
    
    
    
    Proposed Industry Numbering Committee (INC) Scope of Work Change
    
    
    23
    
    
    
    NeuStars Proposed Solution
    
    
    54
    
    
    
    Assumptions and Risks
    
    
    65
    
    
    
    Cost Assumptions and Summary
    
    
    76
    
    
    
    Conclusion
    
    
    7
 
 NeuStar, INC. 2008
    
    iii




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1
    
    Introduction
 1.1
    
    Purpose and Scope
 1
  1.2
    
    Modification of Guidelines
  2
  
 1
    
    Contract Number CON03000016 and the NANPA Technical Requirements Document, March 2003.2
    
    NANPA Technical Requirements Document, March 2003, Section 2.10, Modification of Guidelines. 
 NeuStar, INC. 2008
    
    1




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2
    
    Proposed Industry Numbering Committee (INC) Scope of Work Change
  
    
    Issue 591: Change Timeline of Part 1 / Part 3 Processing for NANPA
  A)
    
    ISSUE STATEMENT
   B)
    
    FOLLOWING RESOLUTION FROM INC
 COCAG
 2.12
    
    An applicant is not required to provide any additional explanation or justification
of items that he/she has certified. However, certification alone may not provide the CO
Code Administrator(s) with sufficient information upon which to make a decision regarding
code assignment, and additional dialog and written documentation may be required. The CO
Code Administrator(s) is still obligated to reply within 7 calendar days. Service
providers participating in number pooling shall apply to the PA for all numbering
resources; i.e., thousands-blocks and full NXX codes. In addition, SPs participating in
number pooling must submit changes or disconnects for pooled NXXs to the PA. Changes or
disconnects for non-pooled NXXs in a pooling rate center should be sent to NANPA, unless
the PA received the original request for the non-pooled NXX.5.2.2
    
    Respond within 7 calendar days from the date of receipt of an application form by
completing the response portion that is part of these guidelines (See Appendix D, II).
For an NXX assigned to a pool, the CO Code Administrator shall also set the Pool
Indicator on the CO Code ACD screen in BIRRDS to designate that the NXX is assigned to a
pool. For those NXXs which the Pool Indicator has been set, the CO Code Administrator
shall provide a Central Office Code (NXX) Assignment Request  Part 3 (Administrators
 
 NeuStar, INC. 2008
    
    2




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3 4
 5.2.10
    
    Respond to the code applicant or the PA in writing via the appropriate Administrators
ResponseReceipt of the Part 4 form within 7 calendar days of receiving the Part 4 or
the Part 4-PA. The response may include, but not be limited to, the following:
 
    
    Part 4 Form Received and Approved
    
    Invalid Part 4 Form Received
    
    Delinquent Part 4 form Received
 6.1.2
    
    Requests for code assignments cannot be made more than six months prior to the
requested effective date. Applicants must request an effective date at least 66 calendar
days after the request is submitted to the PA via PAS or an effective date at least 59
calendar days after the request is submitted to the NANPA via NAS.
  5
 
 3
    
    FCC 01-362, § 52.15 (g)(4).4
    
    FCC 00-104, ¶ 98.5
    
    The 21-day interval is the combination of 7 calendar days for the PA, 7 calendar days
for the NANPA, and 7 calendar days for the AOCN. 
 NeuStar, INC. 2008
    
    3




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##### 



6.1.2.1
    
    Requests to open, modify, or disconnect a code in fewer than 66 or 59 calendar days (see
above) increases the potential for call blocking and/or billing errors and should be avoided
except in emergency cases. If an SP must seek an expedite, the burden of implementation is
borne by that SP and does not obligate any other SP to activate the code in fewer than 45
days.
  a)
    
    The expedited 21-day or 14-day Interval activities:
 
    
    In addition to submitting the Part 1 form to the PA or NANPA, the SP obtains
agreement from its AOCN to input the Part 2 data within a specific negotiated time
period. This can reduce the AOCN period down from 7 days. The SP must provide
written confirmation to the PA or NANPA of the reduction of the 7 days. In the case
where a Code Applicant/Holder acts as its own AOCN, the Code Applicant/Holder
should indicate so on the Part 1. Doing so will reduce the AOCN period down from 7
days.
    
    Then, the SP submits the Part 1 form through the PA or NANPA with the attached
confirmation from the AOCN if applicable.
    
    When the SP requests to receive the earliest effective date on the Part 1
form, NANPA will reduce the effective date to the earliest date without
compromising the 45-day code activation interval from the date NANPA processes the
request.
  
    
    The SP must follow the Network Interconnection and Interoperability Forum (NIIF)
procedures to expedite the 45-day code activation process.6
    
    On an exception basis, an activation interval of less than 45 calendar days may
be requested on the Part 1. Under no circumstances will an activation interval of
less than 30 calendar days be approved by the homing tandem operating company or
the NANPA.
    
    To open a new code, the Part 1 must be accompanied by documentation from the
homing tandem operating company that the shorter interval can be met.
    
    To modify or disconnect an existing code, NANPA may have a direct role such as
entering changes to data on the BIRRDS ACD screen. For disconnects, NANPA has the
direct role of entering the effective date of the disconnect on the ACD screen. If
an expedite is approved, the expedite information will be entered in the BIRRDS ACD
screen as well. When NANPA has a direct role, NANPA has the discretion to grant an
expedite without concurrence from the homing tandem operating company. Under no
circumstances will a modification or disconnect interval of less than 30 days be
approved by the NANPA.
 
 6
    
    For more information, refer to the latest issue of NIIF-008 Recommended Notification
Procedures to Industry for Changes in Access Network Architecture. 
 NeuStar, INC. 2008
    
    4




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8.2.2
    
    If a Part 4 has not been received by the Administrator during the first five months
following the original effective date returned on the Part 3 and entered on the ACD screen in
BIRRDS, then the Administrator will send, via facsimile/electronic mail, a reminder notice to
the code assignee. The notice will be sent no later than one month prior to the end of the
6th month, and will direct the assignee to do one of the following by the end of
the sixth month after the original effective date returned on the Part 3 and entered on the
ACD screen in BIRRDS:
 
    
    For non-pooled codes, submit the Part 4 to the CO Code Administrator. If the PA
received the original request for the non-pooled NXX, then the CO Code Administrator will
process the Part 4 and respond to the applicant and the PA in writing via the appropriate
Administrators Response  Receipt of the Part 4 form within 7 calendar days of
receiving the Part 4. The PA then will update its records.
    
    For pooled codes, submit the Part 4 to the PA.
    
    If the code is no longer needed or not in service, return the code by submitting a
Part 1.
 COCAG Part 1
 
 o
    
    By selecting this checkbox, I acknowledge that I am requesting the
earliest possible effective date the Administrator can grant. Please note that
this only applies to a reduction in the Administrators processing time, however
the request will still be processed in the order received.
 3
    
    NeuStars Proposed Solution
  
 NeuStar, INC. 2008
    
    5




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4
    
    Assumptions and Risks
  Assumptions:
 
    
    Service providers must indicate their desire to have the earliest possible effective date
by checking the new field on the application at the time the application is submitted. Such a
request made after the application has been submitted may not be granted.
    
    Expedited code requests will continue to be addressed per Section 6.1.2.1 of the Central
Office Code Assignment Guidelines. Code expedites are only granted if the applicant provides
the appropriate supporting documentation, per Section 6.1.2.1, and that documentation
accompanies the Part 1 application. The purpose of the new check box on the Part 1 application
is to alert NANPA that the applicant does not request a specific effective date, but rather
the earliest effective date NANPA can approve, without treating the request as an expedite.
    
    Required changes in PAS to reflect the reduced NANPA processing intervals as well as the
new data field on the Part 1 central office code application form will take place
simultaneously with the implementation in NAS.
 Risks:
 
    
    The reduced processing interval may result in an increased quantity of suspended
applications. Specifically, applications containing minor errors that require additional
information from the applicant or applications requiring NANPA to obtain a report from NPAC on
possible telephone number porting on a code (e.g., applications returning a code or requesting
a rate center change) may need to be suspended by NANPA as there is less time within the new
processing window to address these matters.
 
 NeuStar, INC. 2008
    
    6




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##### 



5
    
    Cost Assumptions and Summary
  6
    
    Conclusion
  
 NeuStar, INC. 2008
    
    7