Is making the link COMSOFT COMSOFT GmbH | AMHS Interoperability | December 2008 | Page 1 AMHS Interoperability AMHS Interoperability AMHS Implementation

is making the linkCOMSOFT

COMSOFT GmbH | AMHS Interoperability | December 2008 | Page 1

AMHS InteroperabilityAMHS Interoperability

AMHS Implementation WorkshopAMHS Implementation Workshop

Chennai, IndiaChennai, India

15–16 15–16 December December 20082008


OverviewOverview

Mixed environmentMixed environment

ATN protocol variantsATN protocol variants

AMHS interoperabilityAMHS interoperability

Impact and limitationsImpact and limitations


Mixed EnvironmentMixed Environment

Transition periodTransition period

AFTNAFTN

AMHSAMHS• ATN/OSI

• ATN/IPS

AFTN AMHS

AFTN AFTN+

AMHS AMHS

AMHSAMHS

AFTN+

AMHS

ATN/OSI

ATN/ISP


End User ConnectivityEnd User Connectivity

AFTN to AFTN AFTN to AFTN

AFTN to AMHS and vice versaAFTN to AMHS and vice versa

AMHS to AMHSAMHS to AMHS

AFTN

AFTN

AMHS

AMHS AMHS AMHSAMHS

AMHSAMHS

AMHSAMHS

AFTN

AFTNAFTN

AFTNAFTN

AFTNAFTN


AMHS over ATN/OSI AMHS over ATN/OSI • Initial approach as per ICAO Doc 9705

• Adopted early by ASIA/PAC Regions

AMHS over ATN/IPSAMHS over ATN/IPS• Introduced to use widespread IP technology

• Optional in ASIA/PAC Regions

ATN Protocol VariantsATN Protocol Variants

??AMHSover

ATN/OSI

AMHSover

ATN/IPS


AMHS Protocol StackAMHS Protocol Stack

AMHS ApplicationAMHS Application• based on OSI 7 layers

AMHS upper layersAMHS upper layers• Layers 5 - 7

• Uniform

• Independent of networks

AMHS lower layersAMHS lower layers• Layers 1 - 4

• ATN/OSI or ATN/IPS

Application

Application Layer

Presentation Layer

Session Layer

7

6

5

4

3

Transport Layer

Network Layer

Data Link Layer2

Physical Layer1


AMHS over ATN/OSIAMHS over ATN/OSI

Transport Protocol Class 4Transport Protocol Class 4

Connectionless Network ProtocolConnectionless Network Protocol

Various sub-networksVarious sub-networks• LAN: LLC1, ...

• WAN: X.25, ...

ATN RouterATN Router• Unique to aviation due to extensions

• Designed to support G/G and A/G

• Open for integration of other sub-networks

4

3

Transport LayerTransport Protocol Class 4 (TP4)

2

LLC1

Network LayerConnectionless Network Protocol (CLNP)

X.25......

CSMA/CD LAPB...

LAN WAN


AMHS over ATN/OSIAMHS over ATN/OSI

Example for a pure ATN/OSI environmentExample for a pure ATN/OSI environment

AMHS Applications operate over LAN (e.g. TP4 / CLNP / LLC1)AMHS Applications operate over LAN (e.g. TP4 / CLNP / LLC1)

ATN Router interconnect using WAN (e.g. CLNP over X.25)ATN Router interconnect using WAN (e.g. CLNP over X.25)

ATN Router

CLNP

Session

Pres.

Appl.

Session

Pres.

Appl.

...

ATS MessageServer

TP4

ATS MessageServer

CLNP

...

TP4

ATN Router

AMHSATN/OSI


AMHS over ATN/IPSAMHS over ATN/IPS

Transport Protocol Class 0Transport Protocol Class 0

Transmission Control ProtocolTransmission Control Protocol

Internet ProtocolInternet Protocol• IPv4 (RFC 1006)

• IPv6 (RFC 2126)

Standard IP RouterStandard IP Router• Interoperability IPv4/v6 by

Network Address Translation andProtocol Translation (NAT/PT)

4

3

Transport LayerTransport Protocol Class 0 (TP0)

RFC 1006 / RFC 2126

2

Transmission ControlProtocol (TCP)

Internet Protocol (IP)

LAN

CSMA/CD


AMHS over ATN/IPSAMHS over ATN/IPS

Example for a pure ATN/IPS environmentExample for a pure ATN/IPS environment

AMHS Applications operate over LAN (e.g. TCP/IP / Ethernet)AMHS Applications operate over LAN (e.g. TCP/IP / Ethernet)

IP Router interconnect using WAN (e.g. TCP/IP over Frame Relay)IP Router interconnect using WAN (e.g. TCP/IP over Frame Relay)

IP Router

TCP/IP

Session

Pres.

Appl.

Session

Pres.

Appl.

...

ATS MessageServer

TP0

ATS MessageServer

TCP/IP

...

TP0

IP Router

AMHSATN/IPS


Coexistance of ATN/OSI and ATN/IPSCoexistance of ATN/OSI and ATN/IPS

How to connect ?How to connect ?

Common Protocol Stack requiredCommon Protocol Stack required

Protocol stacks are not compatible!Protocol stacks are not compatible!

ATN Router

CLNP

Session

Pres.

Appl.

Session

Pres.

Appl.

...

ATS Message Server

TP4

ATS Message Server

TCP/IP

...

TP0

IP Router

?AMHS

ATN/OSIAMHS

ATN/IPS


AMHS using Dual Stack RouterAMHS using Dual Stack Router

Example for a dual stack routerExample for a dual stack router

AMHS End Systems operate over LANAMHS End Systems operate over LAN

ATN Router implements both stacks and a ATN Router implements both stacks and a Transport BridgeTransport Bridge

Dual Stack Router

Session

Pres.

Appl.ATS Message

ServerATS Message

Server

TCP/IP

...

TP0

IP Router

CLNP

Session

Presentation

Application

...

TP0

TCP/IP

...

AMHSATN/OSI

AMHSATN/IPS

TP4


AMHS using Dual Stack ApplicationAMHS using Dual Stack Application

Example for a dual stack ATS Message ServerExample for a dual stack ATS Message Server

AMHS Application implements both stacks AMHS Application implements both stacks ATN Router interconnects using ATN/OSIATN Router interconnects using ATN/OSI IP Router interconnects using ATN/IPSIP Router interconnects using ATN/IPS

ATNRouter

Session

Pres.

Appl.ATS Message

ServerATS Message

Server

TCP/IP

...

TP0

IP Router

CLNP

Session

Presentation

Application

...

TP0

TCP/IP

...

AMHSATN/OSI

AMHSATN/IPS

TP4

IP Router


AFTN/AMHS GatewayAFTN/AMHS Gateway

Interconnects AMHS with AFTNInterconnects AMHS with AFTN• Seamless transition from AFTN to AMHS

• AFTN – AFTN over AMHS

Bi-directional message exchangeBi-directional message exchange• ATS Messages

• Conversion of addresses and contents

• Limitations from AMHS to AFTN

Transparent to end usersTransparent to end users

End users can migrate any timeEnd users can migrate any time


AFTN/AMHS GatewayAFTN/AMHS Gateway

AFTN – AMHSAFTN – AMHS• AFTN/AMHS Gateway on AFTN side

AFTN – AFTNAFTN – AFTN• AFTN/AMHS Gateway

on both sides

AFTN

AFTN

AFTN/AMHSGateway

AMHS

AMHSAMHS

AFTN/AMHSGateway

ATS MessageServer


Interoperability TestsInteroperability Tests

Ensure interoperability of products from different suppliersEnsure interoperability of products from different suppliers

ASIA/PAC AMHS ManualASIA/PAC AMHS Manual• Conformance (Annex B)

• Interoperability (Annex E)

• Per-Operational (Annex F)

ATN Routers and AMHS Applications are interoperableATN Routers and AMHS Applications are interoperable• Trials

• Interoperability tests

• Daily operation


Plans for ASIA/PAC RegionsPlans for ASIA/PAC Regions

Strategy for ATN/IPS in ASIA/PAC is under considerationStrategy for ATN/IPS in ASIA/PAC is under consideration

Backbone systems implement dual stack solutionsBackbone systems implement dual stack solutions• ATN/OSI

• ATN/IPS

Non-backbone system mayNon-backbone system mayimplement ATN/OSI or ATN/IPSimplement ATN/OSI or ATN/IPS

Long-term objective: ATN/IPSLong-term objective: ATN/IPS


SummarySummary

Coexistance of ATN/OSI and ATN/IPSCoexistance of ATN/OSI and ATN/IPS• Dual stack routers or applications

Integration of AFTN usersIntegration of AFTN users• AFTN/AMHS Gateway

Transparency for end usersTransparency for end users• AFTN

• AMHS

Interoperability TestsInteroperability Tests• ASIA/PAC: AMHS Manual

• EUR: ECG initiative and AMHS Manual


Thank you !Thank you !

[email protected]@COMSOFT.aero

Documents

Is making the link COMSOFT COMSOFT GmbH | AMHS Interoperability | December 2008 | Page 1 AMHS Interoperability AMHS Interoperability AMHS Implementation