1. © 2010 The MITRE Corporation. All rights reserved. AERONAUTICAL COMMUNICATIONS PANEL (ACP) THIRTEENTH MEETING OF THE WORKING GROUP I Bangkok, Thailand 27 – 28 January 2011 INFORMATION PAPER FAA use of ATN over SCTP R. Morgenstern, MITRE FAA Data Communications Program System Engineering

2. © 2010 The MITRE Corporation. All rights reserved. Aircraft Avionics TOWER Data Comm Services APPROACH Data Comm Services CENTER Data Comm Services Air-Ground Data Comm Network Service FAA Data Communications: Scope

3. © 2010 The MITRE Corporation. All rights reserved. DCP Architecture 3

4. © 2010 The MITRE Corporation. All rights reserved. NAS Boundary Protection Processors in NAS Enterprise Security Gateway (NESG) terminate all in-bound connections and proxy applications 4

5. © 2010 The MITRE Corporation. All rights reserved. Protocol Gateway Since the Protocol Gateway (PGW) processor is terminating TP4 connection to aircraft, FAA decided to also convert protocols to IPS to simplify End System (ES) and intervening network implementations Utilizing SCTP (IETF RFC 4960) to manage line failures Using a modified ICAO Doc 9896 Dialog Service to communicate between PGW and ES –Supports both ATN and FANS –Use TCP requirements in Doc 9896 as model for SCTP 5

6. © 2010 The MITRE Corporation. All rights reserved. Protocol Stack 6 PGW Dialog Service – Modified ICAO Doc 9896 Dialog Service Multiplexing Service – Supports ground routing to ES Connectivity Service – Supports management of failovers

7. © 2010 The MITRE Corporation. All rights reserved. FANS Support Use D_UNIT_DATA for connectionless communications –Encode SMI at beginning of User Data –Aircraft Registration field used as aircraft Peer ID Utilize new Application Technology Type encodings to signal FANS message with and without Message Assurance encoding Use 16-bit sequence number to support Message Assurance Service (MAS) Use D_ACK message to convey A620 notifications to ES via added User Data –MAS Reports, Service Messages, Reject Messages, Outage notifications 7