# Presentation: 510282

## Modular, Cost-Effective, Extensible Avionics Architecture for Secure, Mobile Communications over Aeronautical Data Links

- 2006 IEEE Aerospace Conference
- Big Sky, Montana
- Will Ivancic
- NASA Glenn Research Center
- _[wivancic@grc.nasa.gov](mailto:wivancic@grc.nasa.gov)_
- 216-433-3494

## NASA’s Request for Comments on theGlobal Air Space System Requirements

## Current View of the Global Airspace System

- Current Global and National Airspace System
- Stove-piped communication systems
- Disjoint set of networks
- Currently not globally network centric
- Evolved over time with limited concern for network security
- Security by obscurity
- Closed systems
- Insufficient bandwidth to support security measures
- Safe and Secure
- Air Traffic Control methods have evolved in reaction to changes in technology, capacity and use
- Current methods are reaching limit of scalability
- FAA - Bringing Safety to America’s Skies
- Mission is to provide the safest, most efficient aerospace system in the world.
- Responsible National Airspace System, not funded to address global issues.
- Movement toward Network Centric Operations
- Cross network security
- Authentication, Authorization, Accounting and Encryption
- Required changes in Policy!

## Global Airspace System Requirements

- Must be value added
- Cannot add cost without a return on investment that meets or exceeds those costs.
- Must be capable of seamless global operation.
- Must be capable of operating independently of available communications link. Must support critical Air Traffic Management (ATM) functions over low-bandwidth links with required performance.
- Must use same security mechanisms for Air Mobile and Ground Infrastructure (surface, terminal, en router, oceanic and space)
- Critical ATM messages must be authenticated.
- Must be capable of encryption when deemed necessary
- Security mechanisms must be usable globally
- Must not violate International Traffic in Arms Regulations
- Must operate across networks owned and operated by various entities
- Must be able to share network infrastructure
- Must make maximum use of standard commercial technologies (i.e. core networking hardware and protocols)
- Must enable sharing of information with proper security, authentication, and authorization
- Situational Awareness
- Passenger Lists
- Aircraft Maintenance
- Same network must accommodate both commercial, military and general aviation.

## Design Concepts

- Must be IPv6 based.
- Must be capable of a prioritized mixing of traffic over a single RF link (e.g. ATM, maintenance, onboard security, weather and entertainment).
- Must utilize IPsec-based security with Security Associations (SAs) bound to permanent host identities (e.g. certificates) and not ephemeral host locators (e.g. IP addresses).
- Must be capable of accommodating mobile networks.
- Must be capable of multicasting
- Must be scalable to tens of thousands of aircraft

## Consensus on Six Major Points

- It is critical that any new technologies being deployed provide a positive return on investment (ROI).
- Network Centric Operations (NCO) will be a major technology in future airspace systems and the next generation Internet Protocol, IPv6 will be the protocol of choice.
- Links should be shared, and the system should be provider-independent.  This makes QoS a requirement.
- A common global security structure must be developed and IPsec is probably the best choice.   Some work still needs to be done regarding IPsec multicast, envisioning a certificate-based security architecture, and figuring out how exactly to do QoS with respect to wireless links and encryption.
- The system must be able to share network infrastructure.
- The system must be extensible to meet future needs.

## Aircraft Communications Addressing and Reporting System  (ACARS) and the Aeronautical Telecommunication Network (ATN)

## Current Avionics Architecture

- ACARS is based upon an all-in-one communications management unit.
- Origin can be traced back to global teleprinter network, telex, established in the 1920s!
- Point-to-point telex network where all messages come to a central processing location
- Today ACARS is widely deployed in commercial airlines.
- ATN network is an attempt to modernize ACARS, using most of the existing radio technologies with limited modifications.
- Deployed in a closed, aeronautics-only network
- Limited flexibility
- Cannot adapt easily to new technologies, new communication protocols, and new communication links
- Security currently is extremely limited at best; however, specifications have been updated in an attempt to rectify this
- Limited bandwidth makes security difficult

## Typical ACARS Onboard Network

- SATCOM AERO-1 System

- SATCOM AERO-H/H+ System

- VHF Voice/DATA System

- HF Voice/DATA System

- GateLink

- File Server Subsystem

- Printer

- ARINC 741

- ARINC 761

- ARINC 740/744

- ARINC 719
- ARINC 753

- ARINC 716
- ARINC 750

- Terminal

- Ethernet
- (Optional)

## Future Air Navigation System (FANS)

- In 1983, FANS originated as study of the current air traffic infrastructure and recommend changes to support the anticipated growth in air traffic over the next 25 years
- The FANS committee identified these needs:
- Replacement of the current analog radios with digital air/ground communications;
- Use of satellite and HF communication systems  to provide communication where deployment of  line-of-sight systems is not practical such as in the oceanic domain;
- Global Interoperability;
- Network-enabled systems to support automation in the airplanes and on the ground;
- Transition to a Global Positioning System (GPS)-based navigation and landing systems; and,
- Installation of flight service automation to enable pilots to plan and file flight plans without reliance on flight service specialists.
- Widely Deployed over ACARS as FANS-1/A

- It is now 2005 – 22 years later, and only an extremely small portion of FANS has been deployed using ATN

## ATN and Mobility

- Uses the Inter-Domain Routing Protocol (IDRP)
- Using a routing protocol to handle mobility effectively requires one to own the entire infrastructure because one generally is not permitted to inject routes into another’s infrastructure.
- If the radio access is not secure and ATN secure routing is not implemented, the system is extremely vulnerable
- A distributed IDRP directory using Boundary Intermediate Systems (BISs) is implemented along with a two level directory approach
- Uses an ATN Island concept consisting of backbone BISs and a home BISs concept
- This is done to limit the convergence time or route updates.
- If the routing structure were to become to large, convergence times would become unacceptable.

## ATN Island Routing Domain Confederation

**ATN TRD**

**ATN TRD**

**ATN Backbone RDC**

**ATN TRD**

**ATN  ERD**

**ATN  ERD**

**ATN Island RDC**

**Mobile RD**

**Mobile RD**

**Mobile RD**

**Another**
**ATN Island**

- ERD – End Routing Domain
- RD – Routing Domain
- RDC – Routing Domain Confederation
- TRD – Transit Routing Domain

## Typical ATN Onboard Network

- Similar to CMU in ACARS Network

## Mobile-IP Based Architecture

## Features of Mobile-IP Based Mobile Networking

- Commercial-Off-The-Shelf technology
- IETF NEtwork MObility (nemo)
- Base functionality is standardized
- Currently working on route optimization
- Rapid Convergence Time
- Link independent (Multihoming)
- Does not inject routes into the infrastructure
- Allows for use of shared infrastructure.
- One does not have to own the infrastructure
- Allows for insertion of new link technologies as they mature.
- Enables competition which should reduce cost
- Policy-based Routing (Currently in development)
- IETF Mobile Nodes and Multiple Interfaces in IPv6 (monami6)

##  IP-Based Transitional Architecture

- SATCOM AERO-1

- SATCOM AERO-HH

- VHF Voice/DATA

- HF Voice/DATA

- GateLink

- INMARSAT Swift 64

- Connexion by Boeing

- WiFi Max

- Cellular

- Future Links

**Mobile Router**

**Cryptography and Firewall**

- Display

-  IP-Based Transitional Architecture

##  IP-Based Architecture with ATC and AOC Separate 

- SATCOM AERO-HH

- VHF Voice/DATA

- HF Voice/DATA

- GateLink

- INMARSAT Swift 64

- Connexion by Boeing

- WiFi Max

- Cellular

- Future Links

**Mobile Router**

**Cryptography and Firewall**

**Cryptography and Firewall**

- Communication and Display

- Sensor Controller  (Optional Display)

-  IP-Based Architecture with ATC and AOC Separate

## IP-Based Architecture with ATC and AOC Combined 

**Mobile Router**

**Cryptography and Firewall**

- Communications Sensor Controller and Display

- Radio Link 1

- Radio Link 2

- Radio Link 3

- Radio Link 4

- Radio Link N

- IP-Based Architecture with ATC and AOC Combined

-  IP-Based Architecture with ATC and AOC Combined

## Policy-Based Routing, All Links Active

**High speed link**

**int2**

**int3**

**Routing ****Policy**

**Routing ****Policy**

**int1**

**Low latency link**

**Reliable link**

**ATC**

**ATC**

**ATC**

**ATC**

**AOC**

**AOC**

**AOC**

**AOC**

**P-DATA**

**P-DATA**

**P-DATA**

**P-DATA**

**P-DATA**

**P-DATA**

**HomeAgent**

- Policy-Based Routing, All Links Active

**ATC**

**AOC**

**P-DATA**

## Policy-Based Routing, Critical Link Active

**High speed link**

**int2**

**int3**

**Routing ****Policy**

**Routing ****Policy**

**int1**

**Low latency link**

**Reliable link**

**ATC**

**ATC**

**ATC**

**ATC**

**AOC**

**AOC**

**P-DATA**

**P-DATA**

**P-DATA**

**HomeAgent**

- Policy-Based Routing, Critical Link Active

**ATC**

## Policy-Based Routing, Passengers Link Active

**High speed link**

**int2**

**int3**

**Routing ****Policy**

**Routing ****Policy**

**HomeAgent**

**int1**

**Low latency link**

**Reliable link**

**ATC**

**ATC**

**ATC**

**AOC**

**AOC**

**AOC**

**P-DATA**

**P-DATA**

**P-DATA**

**P-DATA**

**P-DATA**

**P-DATA**

- Policy-Based Routing, Passengers Link Active

## Achieving Positive Return on Investment

## Internet Protocol Value Added Features

- Lower Telecommunication Costs of IP-based networks as compared to dedicated point-to-point links
- Competition among information providers
- Economies of scale
- Lower development costs for new applications and maintenance due to standardization of interfaces

## Link Independence

- Most important considerations for this is not technical, but related to cost, safety, and politics
- Facilitates globalization and supports positive ROI
- Requires change in policy
- Change in use of spectrum
- World Radio Conference to allow use of other frequencies for air traffic control messages
- Air Traffic Controller is now networked.

- These are some very different modes of  operation from what the aeronautics community is comfortable with.

## Airplanes and Automobiles

- Commercial airlines make up only 4% of the active civil aircraft
- – approximately 15,000 out of a total of 215,000 aircraft
- “Airbus forecasts that of this total, 16,600 new passenger aircraft of more than 100 seats will be needed in the coming 20-year period
- Today, 700 million cars are globally deployed for a human population of 6 billion.
- Toyota expects to produce 9.2 million vehicles in 2006.
- General Motors produce approximately 9.1 million vehicles in 2005

## Applications for Mobile Platforms

- Car-to-car communication (plane-to-plane)
- Driver assistance information
- ITS taxi service where the taxi company runs a system to distribute the best taxi based on the locations, idle/operation information. (Air Operations)
- Probe servers collects and distributes information gathered by various probes
- Car inspection information and maintenance log Preventative maintenance (Air Operations)
- Probe data analysis and synthesis where time/location data among various probe data can be integrated to create traffic information. (Air Traffic Management)
- Vending machine networks where vending machines can become wireless LAN access points, to offer broadband wireless communication infrastructure. (Surface Area)
- Large volume content distribution service (Electronic Flight Bag)
- Encrypted data contents can be downloaded onto car-equipped devices and decryption key can be sent later to enable a new type of distribution, which lowers communication cost and makes download operation transparent.
- Next-generation road service where computer-assisted road service automates the process of locating and  failure of a broken-down car and towing it to a desired destination.  (Air Operations)

## Backup Slides

## Car-to-Car Communications

- Mission and Objectives
- Create and establish an open European industry standard for Car2Car communication systems based on wireless LAN components
- Guarantee European-wide inter-vehicle operability
- Enable the development of active safety applications by specifying, prototyping and demonstrating the Car2Car system
- Promote the allocation of a royalty free European wide exclusive frequency band for Car2Car applications
- Push the harmonization of Car2Car Communication standards worldwide
- Develop realistic deployment strategies and business models to speed-up the market penetration

- Technical Approach
- Use of IPv6
- Utilize 802.11 wireless LAN technology
- Ad hoc routing capable of handling rapid changes in topology

- <footer>Source: Car2Car Communication Consortium

## Security Mechanisms

- Encryption mechanisms should be limited to those that are free of ITAR restrictions
- Other counties also have regulations restricting the exportation of cryptography technology
- These regulations may limit the ability to realize cost and schedule advantages that could be gained by using a single set of proven security infrastructure software throughout the world.
- Multicast and *current* IPSec implementations do not necessarily work well together.
- Support for IPSec-base security with Security Associations bound to permanent host (multicast group) identities (e.g. certificates)
- Location, control, and responsiveness of the authentication authority servers is critical.