Transcript ATN2003 - ATN Conference

A Reusable Software Component (RSC)
Approach for the ATN Protocol Stack
Presented by Thales Avionics
ATN 2003
London, UK
23-24 September 2003
ACI’s Certifiable ATN RSC
Baseline
ACI: Pioneer in ICAO SARPs-compliant ATN Router RSCs
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ACI Partners: Honeywell, Thales ATM, Thales Avionics, Sofreavia
Operational deployments for FAA CPDLC Projects
 CSC DLAP and Miami ARTCC Ground BIS Router delivered 2000
 In operational service from 2002 for FAA Build I Program
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Final release of basic ATN RSC delivered to ATNSI mid-2003
ACI ATN RSCs developed in close coordination with FAA
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ACI coordinated design planning and development with FAA
TRUST team (AIR-120) FAA guidelines for RSC methodology
FAA audits (SOI 1-2-3-4) and DER follow-up assured that
DO178B Level C RSC production objectives were met
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If the ATN RSC is “done”, why
evolve the RRI ?
ATNSI/ACI RRI forms basis for an ATN RSC product line
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RRI RSC specified (1996) for airborne/ground-based ATN OEM needs
Problem: VDL/2 specifications not complete at RRI specification freeze
Result: RRI RSC can be used for VDL/2, but efficiency-enhancing and
DSP-specific VDL2 optimizations are missing
As software supplier to the avionics industry, Thales Avionics
decided to develop a product line filling the VDL/2 gap…
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Thales Avionics ATN VDL/2 RSC product derived from initial RRI RSC
First RRI-based avionics ATN VDL/2 router furnished in 2002
Followed-on with first avionics build for in FAA Build 1 in 2003
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Thales Avionics
DO178B Level C ATN RSC
CM, CPDLC, ADS RSCs
ASE RSC development
RRI RSC
RRI RSC development
ACI
ACI & ATNSI
Cert/Nav Authority
Coordinate Certification & SOI/Audit
VDL/2 RSC
ATN VDL/2 RSC
Cert/Nav Authority
Common Certification Artifacts
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VDL/2 Features in
Thales Avionics ATN VDL/2 RSC
Supports VDL Mode 2 Handoff
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Acquisition and processing of ATN Handoff events in Internetworking
and Subnetwork Dependent Convergence Function (SNDCF) layers
Maintains subnetwork compression context after VDL RGS Handoff
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Maintains PLP (X.25) local references & connection information
Avoids renegotiating and rebuilding mobile compression data
Enhances transmission efficiency on the VDL2 link
Supports Call Redirection Facility
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Ground PLP (X25) may redirect call to another router, allowing access to
any VDL Mode 2 compliant sub-network
Support for both DSPs
 ARINC: Ground RTR X.25 address references VPDN
 SITA: Ground RTR X.25 address redirected using X.121 addressing facility
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Supports balancing of traffic load & ensures inter-DSP compatibility
ISH PDU processing compliant with current ARINC 631 policy
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As an OEM, why use an RSC ?
Move from the traditional software development and certification
approach (specific development for a specific target)
TO
A reusable software approach, DO178B Level C AC20 RSC solution
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Platform independent solution
 Multi-platform target
 Stand-alone certification artifacts and life cycle data
 Certification credit usable after first approval, on subsequent implementations
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Transfer DO178B Level C RSC certification artifacts & life cycle data to
desired development environment & target platform
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The RSC Principle
OEM
Target 1
Target 2
DSP
Proto3
Host 1
Host 2
RSC Certification
ACCEPTANCE
Certification & Navigation
Authority
Reuse in subsequent programs, by other applicants and/or integrators
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From RSC to Integrator
SYSTEM DOC.
Planning
Documents
HLR
CERTIFICATION
3
2
1
1
CERT/NAV
Authority
INTEGRATION
Porting
Guides
Level C
1. System Integrator Linkage
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SRS
High
Level
testing
SPEC
EICD
Verification
traceability
& Coverage
SDD
CODE
TEST 1
IN A, B
OUT
LL
testing
Code
RSC
DEVELOPMENT
Requirements Traceability
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High
Level
testing
Level D
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High level requirements to system
requirements (ATN baseline
requirements are ICAO SARPS and
PICS)
RSC plans to System planning
documents
2. RSC defines required porting in
Porting Guide - System Integrator
builds porting links around RSC
3. System Integrator use RSC low
level tests and functional tests –
runs tests on OEM target
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Ease of Portation
STREAMS design levies minimal requirements on Hardware
platform (minimum customization based on target OS)
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Only two basic OS services need be made available thorough a
specific customization module
 Static Memory Management
 Event Timers
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Simple data exchange mechanism among stack modules and
application modules
Also designed for partitioning between RRI and non-level C
applications
Designed to facilitate certification
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Plans, artifacts, tests & instructions ready for certification re-use
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How to get “airborne” with the
Thales Avionics ATN RSC
The hosting environment exists today…
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VDR (compliant A750 supporting VDL Mode 2 RF communication)
A communications unit ready to host the ATN VDL/2 RSC
Context Management and CPDLC applications with FAA/LINK
2000+ message sets (ED110)
 Many aircraft are now ready for installation of the
DO178B Level C certification-ready ATN VDL/2 RSC
Communications
Unit
ATC
CM/
ATN
CPDLC
AIR-GROUND HMI
DATALINK
FMS
radio
Flight
Parameters
ATN-VDL2
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Thales Avionics ATN VDL/2 RSC
allows OEMs & users to enter
the Level C ATN world today !
CONTACTS
Forrest Colliver
Cedric D’Silva
ATN 2003 (London)
[email protected]
[email protected]
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