Computer Networks & Software Inc

Computer Networks & Software Inc.

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www.CNSw.com

Accelerating CNS

Aviation Applications Using IPv6

Chris Wargo

ATN 2004 Conference

Accelerating CNS

Computer Networks & Software, Inc 2

Agenda

? Content Roadmap & Background ? CPDLC over IP? AEEC Part 8 - IP Transitions ? IPv6 QoS? VSATS & AI-CIE? Challenges

Many of the technical activities presented in this paper were supported under contract to the NASA Glenn Research Center, Cleveland, Ohio (Robert Kerczewski and Mike Zernic, NASA Program Managers)

Accelerating CNS


1999 2000 2001 2002 2003 2004 2005

Aero Appl over IP Study

CPDLC over IP (Build A) NASA Aerosapient Flight Tests

IETF IAB Wireless Workshop

SATS Project Airborne Internet (AI) Definition and Testbed

IP Studies Op Benefits, Cost & Prel Architecture

DARTS AI ship sets delivered

AI Consortium Formulation

NASA/Eurocontrol Project related to iPAX

CIE Concept added to AIC

VSATS – AIU (XML/EFB)

AEEC Project 664 (& Part 8 – ATN harmonization)

CIE – Collaborative Information EnvironmentVSATS – Virginia Small Aircraft Transportation

SystemIAB – Internet Architecture BoardAIU – Aircraft Interface Unit

ICAO ACP WG N

Content Roadmap

Accelerating CNS


Challenge for the Aeronautical World

? Can TCP/IP protocols meet Aeronautical Application Requirements?

? Benefits:– Lower infrastructure cost– Potential for new services:

» QoS» VoIP» Multicast» Security» Integration with existing infrastructure

? Challenges:– Modifying political agreement/ Industry Standards– Addressing technical issues for:

» Mobility management» Policy based routing capability, and others

Accelerating CNS


Our Conclusions Result from a Series of Studies

Aeronautical Applications over TCP/IP and ATN

Potential Aviation Enhancements AchievableThrough the Use of TCP/IP

ATN Transport and Network Layers Implementation Cost Analysis

TCP/IP Architecture for Aviation

Studies performed under funding from the NASA Glenn Research Center

Accelerating CNS


Elements of the Studies

? Technical comparisons of ATN and TCP/IP? Identification of IP based services beyond the current

ICAO ATN– File Transfer– Voice over IP– Web-Casting– Multicasting– Streaming Media– Quality of Service– Security– Network Management

Accelerating CNS


Elements of the Studies (Cont’d)

? Wireless industry developments? Related industry programs and standards ? Operational analysis of future use of IP based services

– Context: Requirements as projected in Free Flight DAG-TM (Distributed Air Ground – Traffic Management)

– Analysis of a number of aviation processes and events– Identification of the use for IP based services in future

aviation processes? Cost Comparison of approaches using ATN or TCP/IP

approaches

Accelerating CNS


Technical Conclusions

? Air-Ground Architecture: ATN and TCP/IP are functionally equivalent.

? Ground-Ground Architecture: ATN uses a more complex, full protocol stack; TCP/IP uses the same protocol stack as the Air-Ground architecture.

? Mobility Support: ATN provides limited mobility support, whereas TCP/IP provides full mobility support including mobility within mobility.

? Security: ATN presently uses Security Labels, which have limited capability; future security will be based on public key infrastructure (PKI). TCP/IP is IPSec-based, which provides more capability; PKI available now.

Accelerating CNS


Technical Conclusions (cont’d)

? Quality of Service: ATN provides limited service; TCP/IP provides flows, RSVP, DiffServ, and real-time protocols.

? Multicasting: ATN does not support; TCP/IP does support.

? Network Layer (Packet) Header: ATN requires more processing; TCP/IP uses streamlined header enabling more efficient processing.

? Network Management: ATN features CMIS/CMIP, which are more complex and limited in implementation. TCP/IP uses SNMP, which is simple, widely tested and available

Accelerating CNS


? Flight Deck

Business – ATM Integrated Flight Deck

A/CC/N/S

Cust entertainment, service, business

Pilot C/N/S, schedule, admin

F/A ops, service, admin

? Passengers...

? Flight Attendants... ? Pilots...

Entire Aircraft !

Accelerating CNS


Integrating Application Communication Requirements

? Each Constituent has Multiple Internal and External Direct Connections with the Others, and the World - creating the air commerce web.

THEAIRPLANE

THE ATMSYSTEM

THEAIRLINE*

Accelerating CNS


IP Enabled AOC/AAC Functions

Flight Dispatch

Freight & Mail Management

Gate Controllers

Aircraft Routing

Meteorology

Hub / Station Operations

Crew Scheduling

Maintenance

Customer Service

Marketing

Sales

Reservations

Accelerating CNS


A Diversion

? Multiple Specific Processes Can be Enhanced

? Diversions - Common Scenario that Touches Many Processes

? Studied three views:– Ideal Current Process– Actual Current Process– Future IP-Enabled Process

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Typical Actual Current Diversion Process

? “Aircraft 429, holding instructions -- advise when ready to copy… ”

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Future IP-Enabled Diversion Process

? Brings together a network rich in opportunities for integration– Airline– ATM System– Airplane

? ATM - Airline Collaboration? Airline - Airline Collaboration? ATM final tweaking

– Defines and transmits Plan– Aircraft receives notification of plan

Accelerating CNS


Future IP-Enabled Diversion Process -- 2

? Aircraft (not just pilot) notification -- expect to:– Be cleared directly in with little or no delay– Be cleared to hold, but expect to get in– Divert immediately to a given alternate

? Customer issues being worked– Passengers headed there for final destination– Re-booking– Alternate transportation– Hotels, etc.

? Planned recovery– Aircraft support systems– Crew scheduling

Accelerating CNS


FlightDeck

Diversion

Etc.

Etc.

Etc.

Etc. Etc.

Etc.

Etc.

Etc.

Weather

AirspaceTraffic

Maintenance

Environment

Passengers

“Hazards”AOC/FD

Station

Ground

Tower

ATM System

“Collaborations”

Law Enforcement

Crisis Management

Safety SystemsAPC

Items

Medical

“Other”

IP-enabled Process Integration

Accelerating CNS


Application Benefits from Future Services

FUTURE SERVICES

AVIATION APPLICATIONS THAT CAN BENEFIT

RE

PO

RT

RE

FER

EN

CE

FTP

VoI

P

Web

-Cas

ting

Mul

ticas

ting

Str

eam

ing

Med

ia

Sec

urity

QoS

Net

wor

k M

gmt

Weather Diversions 4.3.1 X X X X X X XPassenger Accommodation Due to Schedule Disruption 4.3.2 X X X XWeather Graphics 2.4.1.2 X X XDatabase Updates 2.4.1.2 X X XMaintenance Procedures and Information 2.4.1.2, 4.3.4 X X XAirport Information 2.4.1.2 X X XDigital Voice as Replacement for Analog Voice F.2.5 X X XDigital Voice fed into Flight Dispatch Status Displays F.2.5 X X XATC Digital Voice Copied to Flight Dispatchers F.2.5, 4.3.5 X X XRoutine Transmissions 2.4.3.2 X X XPre-Flight Briefings 2.4.3.2, 4.3.6 X X X

Accelerating CNS


Selected FD-Centric, IP-enabled Applications

Technology AppliedApplication Comments

FTP

Stre

amin

g M

edia

Web

-Cas

t

Mul

ticas

t

VoIP

Addr

esse

d/E

-mai

l

QoS

Sec

urity

Dat

a B

ase

FD HAZARD INFORMATION

WEATHER STATUS

- ATIS, etc. Currently available text products X X x

- Graphical WeatherStrategic and tactical flight conditions,enroute winds, RVR, ceiling,winds/crosswinds— the entire AWINgamut

X X X X

- PIREP and E-PIREPtransmission/reception Completely or semi-automated X X X X X X x X

- Ownship radar picture sharingWith dispatch, ATSP, other nearbyaircraft. Especially useful in holdingsituations.

X X X X X

AIRSPACE STATUS

- NOTAMS, etc. Currently available text products X X X X

- Strategic Graphical DepictionsDynamic hot/cold MOAs. WarningAreas, ADIZ, Restricted Areas,Airways, LLTRs, etc.

X X X X

- Tactical Graphical Depictions

Active runways, active arrival &departure routings, active holdingpatterns, active taxi routing, gateassignments, etc.

X X X X X

- Graphical and AlphanumericLegal Conditions

Runway conditions, taxiwayconditions, de-icing requirements, etc.

X X X X X X X

Accelerating CNS


Selected FD-Centric, IP-enabled Applications

Technology AppliedApplication Comments

FTP

Stre

amin

g M

edia

Web

-Cas

t

Mul

ticas

t

VoIP

Addr

esse

d/E

-mai

l

QoS

Sec

urity

Dat

a B

ase

FD COLLABORATION WITH:

AOC / INTRA FD

- Re-routing Planning, filing, notification,acceptance, execution.

X X X X X X

- Flight planning next flight Planning, filing, notification,acceptance.

X X X X X X

- Crew Resource Issues Duty Days, Reassignments, Hotellocations, ground transportation, etc.

X X X X

- Cabin management issuesIn flight video/pictures and appropriatetelemetry shared for medicalemergencies, disruptive passengers,etc.

X X X X X X

- Holding Selecting allowable time, location, etc. X X X X X

- Alternate StationThe need to declare or release analternate for FAR legality. Whichone(s) to use, fuel required, etc.

X X X X X X

- Diversion StationLocation, capability to handle,limitations, expected departure time,etc.

X X X X X X

Accelerating CNS


Potential Savings TCP/IP over ATN

Organization TP4/CLNP TCP/IPv6 DifferenceAirlines

AircraftES & IS Software 30,010,800 2,500,900 27,509,900

Airline Operations ControlAir/Ground Router 3,937,500 26,250 3,911,250Ground/Ground Router 3,937,500 26,250 3,911,250Host (ES) 1,531,250 61,250 1,470,000

Subtotal 39,417,050 2,614,650 36,802,400Business Aircraft

ES & IS Software 37,634,295 3,136,191 34,498,104General Aviation Aircraft

ES & IS Software 48,459,000 4,038,250 44,420,750FAA

Air/Ground Router 63,375,000 422,500 62,952,500Ground/Ground Router 63,450,000 423,000 63,027,000NAS Router

2,812,500 405,000 2,407,500

Host (ES) 24,200,000 734,000 23,466,000Subtotal

153,837,5001,984,500 151,853,000

MilitaryAircraft

ES & IS Software 13,812,000 1,151,000 12,661,000Air/Ground Router

26,812,500178,750 26,633,750

Host (ES) 5,125,000

205,000 4,920,000

Subtotal 45,749,500 1,534,750 44,214,750Communication Service Provider

Air/Ground Router 63,450,000 423,000 63,027,000Total 388,547,345 13,731,341 374,816,004

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NASA GRC System Testbed Configuration

GroundController

Display

CMU(ATN

compliant)

CMU(ATN

compliant)

NASA ExperimentalCPDLC Ground

System

• ‘MCDU’

NASA

NASA DC-8Experimental

Aircraft

VHFDatalink

Testbed Protocol Stack

LAN

• Telemetry• Admin

Physical

MAC

COTP TCP

FastByte COSP

FastByte COPP

Application Service Element (ASE)

Controller Pilot Data Link

Communications(CPDLC)

ContextManagement

(CM)

Transport Switch TransceiversDisplay

‘MCDU’

CLNP IP

‘CMU’

Association Control Service ElementDialogue Service

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*Part 8 AEEC 664 On Board ATN Harmonization

? Committee work involved the development of a approximately 12 different reference models of connectivity

? These were discussed and evaluated? Working consensus developed on depiction of

transition model and approach? Work should be considered as input to the ICAO ACP

WG N current survey of interest

Part 8, AEEC 664 Working Paper – Interoperation with non-IP Protocols and Services

Accelerating CNS


Applications and Sockets Application Program Interface

ping trace route app app app app ping trace

route

UDP

datalink

ARP, RARP

IPv4 IPv6 ICMPv6 ICMP 32 bit address

128 bit address

API

TCP

IPv6 applications IPv4 applications ping trace

route app app app app ping trace route

UDP

datalink

ARP, RARP

IPv4 IPv6 ICMPv6 ICMP 32 bit address

128 bit address

API

TCP

IPv6 applications IPv4 applications

Accelerating CNS


Part 8 AEEC 664 – IP Transition *

CPDLC CM

DS

TP4

CLNP

Ground

Subnet

IP SNDCP

CLNP IP4

CPDLC CM

DS

TP4

CLNP

Subnet

Aircraft

A/G Router

CPDLC CM

DS

TP4

IPv6

Subnet

IPv6G/W

IP6-CLNP

CLNPIP

SNDCP

CPDLC CM

DS’

TCP

IP6

Subnet

CPDLC CM

DS’

TCP

IPv6

Subnet

IDRP

Security - Optional Security

IP6 +Mobile Aeronatical IP

1

2

3

CPDLC CM

DS

TP4

CLNP

Ground

Subnet

IP SNDCP

CLNP IP4

CPDLC CM

DS

TP4

CLNP

Subnet

Aircraft

A/G Router

CPDLC CM

DS

TP4

IPv6

Subnet

IPv6G/W

IP6-CLNP

CLNPIP

SNDCP

CPDLC CM

DS’

TCP

IP6

Subnet

CPDLC CM

DS’

TCP

IPv6

Subnet

IDRP

Security - Optional Security

IP6 +Mobile Aeronatical IP

1

2

3

* Part 8, AEEC 664 Working Paper – Interoperation with non-IP Protocols and Services

Accelerating CNS


Part 8 AEEC 664 On Board Harmonization

ASE

Fast Byte COPPand COSP

DS

ACSECF

TCP

IP

Application

ASE

DS

ACSE

TCP

IP

Transport ServiceConvergence

Function

TP4 Services

TCP Services

ASE


DS

ACSECF

TCP

IP

Application

ASE

DS

ACSE

TCP

IP


Function

TP4 Services

TCP Services

ASE

Fast ByteCOPPCOSP

DS

ACSECF

TCP

IP

Application

ASE

DS

TCP

IP


Function

DS Services

TCP Services

ASE

Fast ByteCOPPCOSP

DS

ACSECF

TCP

IP

Application

ASE

DS

TCP

IP


Function

DS Services

TCP Services

at Dialog Service Interfaceat Transport Service Interface

Accelerating CNS


ASE


DS

ACSECF

TCP

IP

FISUser

ASE


DS

ACSECF

TP4

CLNP

FMC Ground

TCP

IP

TP4

CLNP

CMU

TP4End Point

TCPEnd Point

TCP <-> TP4 Transform(Transport Gateway)

AirSubnetwork

Air/GroundSubnetwork

Wireless Links

XPORT

CMUser

ADSUser CM

UserADSUser

CPDLCUser

CPDLCUser FIS

User

ASE


DS

ACSECF

TCP

IP

FISUser

ASE


DS

ACSECF

TP4

CLNP

FMC Ground

TCP

IP

TP4

CLNP

CMU

TP4End Point

TCPEnd Point

TCPEnd Point

TCP <-> TP4 Transform(Transport Gateway)

AirSubnetwork

Air/GroundSubnetwork

Wireless Links

XPORT

CMUser

ADSUser CM

UserADSUser

CPDLCUser

CPDLCUser FIS

User

Transport Layer Gateway - Distributed ATS Architecture

Accelerating CNS


Objectives - NASA/Eurocontrol Cooperation

? Leverage mutual IPv6 activities for aviation– NASA GRC’s R & D in Aeronautical Telecommunications

Network (ATN) over IP and work in Mobile IP– Eurocontrol’s Internet Protocol for Aviation Exchange (iPAX)

Project? Foster IPv6 research and development activities to support

International Civil Aviation Organization (ICAO) standardizationactivities

? Understand transition issues and technical approach for addressing and interoperability between ISO and IP networks

? Demonstrate ATN related services over IPv6: e.g., Controller to Pilot Data Link Communications (CPDLC)

? Publish technical papers in international proceedings defining the use of IPv6 in aviation

Accelerating CNS


Why IPv6 ?

? High Scalability– 128-bit addresses allows 3.4 x 10 ^ 38 addresses

? Improved support for QoS, mobility? Built in IP Security? Fixed Length Header? Internet Protocol for the future

– In US, DoD plans to move to an all IPv6 network by 2008– In Europe, iPAX has investigated the ways to move from

X.25 networks to IPv6 based networks

Accelerating CNS


IPv6 Testbed (NASA/Eurocontrol)

NASA2000:0:340:BB00::/64

Eurocontrol2000:0:340:2200::/64

CNS2000:0:340:AA00::/64

IPv4Internet

IPv6 over IPv4 tunnels

Aircraft2001:0:340:BB00::3

Aircraft2001:0:340:BB00::15

Controller2000:0:340:AA00::1004

Accelerating CNS


NASA – Eurocontrol IPv6 Test Infrastructure

NASA GRC

CNS AS 1

2001:0:340:2200::/64

IPv6-in-IPv4 Tunnels

2001:0:340:AA01::/64CNS AS 2

CNS AS 3

EUROCONTROL2001:0:340:BB00::/64

2001:0:340:AA02::/64

2001:0:340:AA03::/64

Controller

Aircraft 3

FASTE Server

Netmon Server

Mobile Node

Host Agent

T1 BackboneCore Router Network

Running BGP

Maximus Theodore

Goliath

Odysseus

Eris

Demeter

Hades

Netmon Agent

IPv4 Network

NAT-PT

Marcus

50+ entities

Accelerating CNS


? We ported our Baseline I CPDLC from the ATN domain system to support IPv6

? Consists of two applications» Human-Interactive Aircraft (HIA)» Human-Interactive Controller (HIC)

? Network connectivity between HIA and HIC applications was tested including wireless components.

CPDLC

Accelerating CNS


CPDLC Application Features

Human Interactive Aircraft

? GUI emulating a MCDU? Builds and transmits CM and CPDLC messages? Decodes and displays received CM and CPDLC massages? Presents a range of appropriate response to choose

Human interactive Controller

? GUI that emulates a generic ATC workstation (CM & CPDLC)

? Transmits and decodes CM and CPDLC messages

Accelerating CNS


IPv6 Quality of Service (QoS)

Two main QoS mechanisms– IntServ

» Makes use of the Flow Label field» QoS per connection» Poor Scalability

– DiffServ» Makes use of the Traffic Class field» QoS by packet type/tag» Excellent Scaling properties

4-BitVersion

8-BitTraffic Class

20-Bit Flow Label

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IPv6 DiffServ

? Classifies packets into behavior aggregates? First six bits of the Traffic Class field, know as DiffServ

Code Point (DSCP), map to a unique Per Hop Behavior (PHB).

? Following PHB’s have been standardized by IETF– Expedite Forwarding (EF)

» Low loss, Low delay, Low jitter, Assured bandwidth» Appears as a virtual leased line.

– Assured Forwarding (AF)» Traffic with the subscribed rate is served with high level of assurance» Four AF classes are defined (AF1, AF2, AF3 and AF4)» Each class supports three drop precedence ( AFx1, AFx2,AFx3, AFx4)

– Best Effort (BE)» Does not guarantee any bandwidth

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QoS for Aviation

? Air Traffic Services require different QoS features– Bandwidth– End-to-end delay

? Proper resources distribution is required? We implement a framework for providing QoS for

three different aviation applications– CPDLC– Surveillance– User Data

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Results – Scenario 3

0 10 20 30 40 50 60 70 80 90 100 1100 120 130 140 1500

0.1

0.2

0.3

0.4

0.5

Time (sec)

Nor

mal

ized

Thr

ough

put

P1P2P3

Normalized Input Traffic

P1: 0.2 P2: 0.3 P3: 0.4

P1: 0.3P2: 0.3P3: 0.4

P1: 0.2P2: 0.3P3: 0.4

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 1500

10

20

30

40

50

60

70

80

Time (sec)

Que

ue S

ize

(pac

kets

)

P3P2P1

Packets Dropped P1: 0% P2: 0% P3: 0%



?Congestion due to increase in CPDLC traffic results in EF class borrowing bandwidth from BE class.?Performance degrades for BE traffic class (13% packet loss)while there is no affect on EF and AF1 traffic classes.

Queue Size Vs TimeNormalized Throughput Vs Time

Accelerating CNS


SATS AI Project Summary

? FAA Technical Contact: Ralph Yost? NASA GRC Project: Mike Zernic and Jim Griner? Project:

– Develop the requirement, architecture, and system level design baselines,

– and establish the evaluation testbed for the Airborne Internet.

? AI Objective: – Consolidate and integrate the exchange of CNS data.– Minimize the number of radios and antennas on an

aircraft. Goal is to provide common access means for all wireless aircraft applications.

? Project Team - Recipients of NASA Aerospace Enterprise, Turning Goals into Reality Award for 2003

Accelerating CNS


SATS: Airborne Internet

Airborne Internet? Provide a comm architecture that delivers aviation

information services in an Internet-like manner where aircraft and ground facilities will be interconnected nodes on a high-speed digital commnetwork.

? 2022 AI Fundamental Characteristics:– Aviation Information System– Integrated CNS - Worldwide compatibility– Seamless connectivity– High user and system capacity

Small Aircraft Transportation SystemSATS develops and integrates emerging vehicle and infrastructure technologies, and, enables access to the vastly under-utilized infrastructure of smaller non-hub airports and airspace. More efficient access to congested hubs will create unimagined transportation speed for more people to reach more destinations.

Accelerating CNS


Generic SATS AI Model

Airborne Internet Infrastructure

Mod

e S

UA

T

SAT

CO

M

VD

L

A/C

LA

N

(AR

INC

664

)

WL-

LA

N

802.

11/1

6

Applications

Subnetworks

Layered Protocol Services

Data Transport Services

Broadcast, Multicast, Unicast

Mob

ility

Net

wor

k M

anag

emen

t

Secu

rity

Qua

lity

of S

ervi

ce

All the similarities to the ATN design challenge of the 1980’s

M U L K E R I N A S S O C I A T E S

A T H E N A

T E C H N O L O G I E S

O L D D O M I N I O N U N I V E R S I T Y O H I O U N I V E R S I T Y

M U L K E R I N A S S O C I A T E S

OP TECHNOLOGIES

COMPUTER NETWORKS & SOFTWARE

StrategicAeronautics

STRATEGIC AERONAUTICS OHIO UNIVERSITY MULKERIN ASSOCIATES

VSATS Member Task Actvities

PM Project ManagementHVO High Volume OperationsLLO Lower Landing MinimumsSSP Single-Pilot PerformanceTSAA Transportation Systems Analysis &

Assessment

Accelerating CNS


VSATS Concept – Using XML

<?xml version="1.0" encoding="utf-8" ?><xs :schema id=" TimeToApproachSchema " targetNamespace ="http:// tempuri.org/TimeToApproachSchema .xsd" elementFormDefault="qualified"xmlns="http://tempuri.org/AlertSchema .xsd" xmlns :mstns ="http://tempuri.org/TimeToApproachSchema .xsd" xmlns :xs="http://www.w3.org/2001/ TimeToApproachSchema "xmlns :msdata ="urn:schemas -microsoft-com:xml-msdata "><xs :element name="Document"><xs :complexType ><xs :choice maxOccurs ="unbounded"><xs :element name="TimeToApproach"><xs :complexType >

<xs :sequence><xs :element name=”MsgSource " type="xs :string" minOccurs ="1" />

<xs :element name=”TargetAddress " type="xs :string" minOccurs ="1" /><xs :element name=”Time " type="xs :long" minOccurs ="1" />

</xs :sequence></xs :complexType >

</xs :element></xs :choice>

</xs :complexType ></xs :element>

</xs :schema>

<?xml version="1.0" encoding="utf-8" ?><xs :schema id=" TimeToApproachSchema " targetNamespace ="http:// tempuri.org/TimeToApproachSchema .xsd" elementFormDefault="qualified"xmlns="http://tempuri.org/AlertSchema .xsd" xmlns :mstns ="http://tempuri.org/TimeToApproachSchema .xsd" xmlns :xs="http://www.w3.org/2001/ TimeToApproachSchema "xmlns :msdata ="urn:schemas -microsoft-com:xml-msdata "><xs :element name="Document"><xs :complexType ><xs :choice maxOccurs ="unbounded"><xs :element name="TimeToApproach"><xs :complexType >

<xs :sequence><xs :element name=”MsgSource " type="xs :string" minOccurs ="1" />

<xs :element name=”TargetAddress " type="xs :string" minOccurs ="1" /><xs :element name=”Time " type="xs :long" minOccurs ="1" />

</xs :sequence></xs :complexType >

</xs :element></xs :choice>

</xs :complexType ></xs :element>

</xs :schema>

AIU XML Time to Approach Msg

EFBEFB

EFB: Courtesy of: Strategic Aeronautics

VSATS Cockpit

AIU – Avionics Interface Unit

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