CPDLC Sweden

1
CPDLC Sweden ATN/IPS based Point to Point
communicationsPurpose, Functionality, Carry out,
Goals and Value

• Presented at ICAO ACP WG-I 10-05-19
• By
• Robin Hughes

2
Purpose

• Develop a Point to Point (P2P) datalink
  communication service over VDL4
• Verify ATN/IPS address protocol defined by the
  ICAO Manual for the Aeronautical
  Telecommunication Network (ATN) using Internet
  Protocol Stack (IPS) Standards and Protocols
  (ICAO Doc 9896)
• Implement datalink services Context Management
  and CPDLC as defined in the ATN/OSI manual (ICAO
  Doc 9880)

3
Objectives
Create a platform for future development of
applications defined by the Single European Sky
Implementing Rule for Datalink services, which is
future proof Ascertain if there are any changes
needed to standards for VDL4 Update the VDL4
groundstations and necessary ground network to
handle Mobile IPv6 traffic Ascertain processes
for achieving certification and meeting safety
requirements Ensuring that all documentation is
in place for successful operational implementation
CPDLC CM
Application Layer
CPDLC CM Designed for OSI
Dialogue Service for OSI -gt MIPv6
TCP/UDP Layer
TCP/UDP Layer
IP Layer
IP Layer
Link Layer
Link Layer
Physical Layer
Physical Layer
4
Project Organisation External input
In all 5 FTEs including manufacturers
contribution External guidance by ICAO
WG-I Functionality validated by Eurocontrol
(Eivan Cerasi) Coordination with FP6 NEWSKY
project
5
Supporting documentation

• ICAO Doc 9880
• MANUAL ON DETAILED TECHNICAL SPECIFICATIONS FOR
  THE AERONAUTICAL TELECOMMUNICATION NETWORK (ATN)
  using ISO/OSI standards and protocols
• ICAO Doc 9896
• Aeronautical Telecommunication Network (ATN)
  Manual for the ATN using IPS Standards and
  Protocols (Doc 9896)
• Eurocae Doc 120B
• SAFETY AND PERFORMANCE REQUIREMENTS STANDARD FOR
  AIR TRAFFIC DATA LINK SERVICES IN CONTINENTAL
  AIRSPACE (CONTINENTAL SPR STANDARD)
• RTCA DO-178B
• Software Considerations in Airborne Systems and
  Equipment Certification
• I.e. All according to governing and open
  standards

6
Network topology during trials
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Availability of ATN/IPS today

• All of Sweden is covered (apart from most
  northern part)
• In all 10 sites have ATN/IPS installed
• The solution coined Ground NEMO has proven most
  beneficial
• Allows considerable bandwidth savings with the
  reduction of a full IPv6 header.
• Virtual NEMO routers set up in the link
  groundstations and move around the network,
  providing the mobility.
• Provides the opportunity to introduce IP services
  to Windows based platforms where a lack of
  mobility stacks is a reality of today, common in
  Electronic Flight Bags
• Allows early benefits/implementation of the
  ATN/IPS network and associated services (e.g. MET
  applications or advisory services)

8
Flight trial carry out

• Demonstration of communication via Controller
  Pilot Datalink Communications (CPDLC) ground/air
• Mimic current implementations of CPDLC as far as
  possible within budget

CPDLC
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NARSIM Air Traffic Control Simulator

• An ATC simulator constructed by NLR and modified
  by LFV.
• Used by LFV for simulations and validations, e.g.
  ERAT, TMA2010.
• Can display live traffic received via ADS-B
  ASTERIX cat 21 messages.
• Extended with data link capability for CPDLC
  messaging.

Flygtrafiktjänsten
9
2008-09-24
10
CDTI Cockpit Display of Traffic Information

• Developed by LFV for use in simulations and live
  trial validations, e.g. D-AIM, Runway Incursions.
• Designed to be used on touch screen laptops.
• Extended with CPDLC messaging capability.

Flygtrafiktjänsten
10
2008-09-24
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Result

• COTS implementation and utilisation of ICAO
  standard enabled realisation in 11 months

Average Median 95 of messages 99 of messages 99.99 of messages
ED 120 Requirement N/A N/A 4 sec 8 sec 40 sec
CPDLC Sweden utilising Ground Nemo solution 1.458s 0.894s 3.5 sec 6 sec 15.8 sec

• Based on per messages in a set of three
  messages.
• Payload was 31, 13 and 31 bytes respectively.
• UDP headers gives total message sizes of 79, 61
  and 79 bytes respectively.
• Message sizes chosen to ensure the latency would
  be based on similar size of messages as most of
  the worst case, i.e. largest, messages defined
  for current CPDLC communications.

12
Value and Maturity

• Utilisation of COTS and open standards in CPDLC
  Sweden for ATN/IPS is in accordance with SESAR
  goals for lower costs of systems and SWIM
• In House developed HMIs are at V2
  (Prototypes)/V3(Live trial)
• Hardware and software ground-air components are
  all at V3/V4 (Industrialisation)

13
Next step

• Implementation of Robust Header Compression
  Framework (ROHC) as specified in RFC 4995
• Reducing the IP headers considerably (4bytes)
• New latency tests are scheduled during October
  2010.
• After the finalization of frequency planning
  parameters for VDL Mode 4, implementation in the
  band 118-137 MHz was finalized. Activities on
  implementation in the band 112-117.975 MHz has
  continued in ICAO Navigation Systems Panel (NSP)
  and in ICAO ACP WG-F. The work is now in its
  final stage.

14
The meeting is invited to

• Note the information presented in this paper
• Note that VDL Mode 4 is available for operational
  services based on IPv6
• Provide advice on how further activities in the
  IPv6 based infrastructure in Sweden can be used
  in support of further verification of the ICAO
  ATN/IPS provisions

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THANK YOU!