Tài liệu Chương 1 Mạng Viễn thông Hàng không - ATN doc

Trường Đại học Bách Khoa Hà Nội Hanoi University of Science and Technology... Trường Đại học Bách Khoa Hà Nội Hanoi University of Science and Technology Mạng Viễn thông Hàng không - ATN

Trường Đại học Bách Khoa Hà Nội

Hanoi University of Science and Technology

Trường Đại học Bách Khoa Hà Nội

Hanoi University of Science and Technology

Mạng Viễn thông Hàng không - ATN

Chương 1

© HUST 2012

Hệ thống Thông tin Hàng Không

Teminologies

3

ATN: A eronautical T elecommunications N etwork

AFTN: A eronautical F ix T elecommunications N etwork

AMHS: A ir T raffic S ervice M essage H andling S ystem

Development Trends

AOC : Aeronautical Operational Control,

AAC : Aeronautical Administrative Communications APC : Aeronautical passenger Communication)

ATSC

ATN Concept

ATN Applications

AIDC: ATS (Air Traffic Services) Interfacility Data Communication

CPDLC : Controller Pilot Data Link Communication

ADS: Automatic Dependent Surveillance FIS: Flight Information Service

CM: Context Management

ATN Architecture

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ATN Architecture

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ATN Architecture

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ATN Routing Domains

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ATN Routing Domains

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ATN Routing Domains

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ATN Routing Protocols

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ATN Routers perform data relay and routing functions for ATN CLNP data packets

Routers in the ATN

ATN Router functions: Data Relay

ES #2 (e.g

AMHS)

APAC ATN Backbone Network

State A Backbone BIS #2

State C Backbon

e BIS #4

State B Backbone BIS #3

ES #1 (e.g

AMHS)

ATS Facility BIS #1

ATS Facility BIS #5

ATN routers relay data packets towards their destinations

The “path” across the network is determined according to least “hops”, ATSC

class etc

“Least hops” route:

ES#1→BIS#1 →BIS#2

→BIS#3→BIS#5→ES#2

AOC via VDL-2

ATN Router functions: Multiple A/G sub-networks

ATN Router functions: Dynamic Routeing

Using dynamic routeing, routers can automatically detect damaged

network elements and re-route traffic

e.g due to failure of link

between BIS#2 and BIS#3,

traffic from ES#1 to ES#2

re-routed via BIS#4

ES #2 (e.g AMHS)

APAC ATN Backbone Network

State A Backbon

e BIS #2

State C Backbone BIS #4

State B Backbon

e BIS #3

ES #1 (e.g

AMHS)

ATS Facility BIS #1

ATS Facility BIS #5

ATN Router functions: Priority Handling

 Multiple applications compete for the “narrow pipe” to the aircraft

 ATN routers handle CLNP NPDUs according to priority when contention for resources or congestion are occurring:

 Lower transit delay for higher priority messages

 Lower probability of higher priority messages being “dropped”

ATIS AOC

CPDLC

ATIS AOC CPDLC

Normally the router forwards

each packet down a link in the

order in which it arrives

If a link is congested, CLNP

NPDUs will start “queueing

up” waiting to be sent,

CLNP NPDUs can be

re-ordered if the link is congested

depending on their priority

ATN Router: Protocols

Domain #B

ATN Router (BIS)

ES ATN

Router (BIS)

ES

ATN or IS Router

ES

IDRP ES-IS ES-IS

- ES-IS: between End Systems and routers

- IS-IS: within a routeing domain

- IDRP: between routeing domains

ATN router functions are defined in ICAO Doc 9735-AN/956 sub-volume V

• Ground/Ground (Class 4) and Air/Ground (Class 5) ATN routers must

implement the IDRP routeing protocol

•All Class 4 and Class 5 routers are Boundary Intermediate Systems (BIS)

Addressing within the ATN

 Addresses are hierarchical, based on nested address domains All

addresses within a domain have the same address prefix

IS

O IC

D

Internati onal Authority

Routing Domain Identifier

Mobile ATSC 470027+C1

Mobile AINSC 470027+41

Fixed AINSC 470027+01

Addressing and its relationship to routeing

 Hierarchical addressing and domains greatly simplify routeing:

 Reduces routeing information exchanged by allowing routers to advertise

aggregate prefixes rather than lists of addresses

 The router only has to inspect the prefix of a CLNP packet’s address to

determine where to send it

Thailand

Japan

Singapore

“I can reach Japan”

“I can reach Singapore

& Thailand”

“I can reach Thailand

”

“I can reach Singapore and Japan” IDRP update PDU

contents

=

“I can reach” = address prefix

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ATN Router Functions: Sub-network interface

CLNP

LLC Type 1 MAC

CSMA/CD

ES

ATN Router

LLC Type 1 MAC

Routing Protocols

（ES-IS, IS-IS,IDRP）

CLNP CLNP

LLC Type 1 MAC

Global ATN Internet

The APAC Regional ATN Ground Network

Source： Fifth ATN Transition Task Force Meeting – WP19

（2003.6）

APAC: Asia/Pacific Region

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Use of APAC ATN Network for Air-Ground

ATN

A/G BIS GES

Japan

ATN communication

（CPDLC,ADS,DFIS ）

Trường Đại học Bách Khoa Hà Nội

Hanoi University of Science and Technology