AFTN AIDC over ATN ICS or IPS

AFTN AIDC over ATN ICS or IPS ACP - WGN06-WPxx AERONAUTICAL COMMUNICATIONS PANEL (ACP) WORKING GROUP N – NETWORKING th6 MEETING – BRUSSELS, BELGIUM, 3 – 7 July 2006 AFTN AIDC over ATN ICS or IPS Prepared by AEROTHAI Summary This paper proposes an alternative to implementation of the ATN AIDC Application as defined in ICAO Doc 9705. The alternative is to adapt the AFTN AIDC application to be block oriented so that it may run over the ATN OSI-based Internet Communications Service or the Internet Protocol Suite. ACP - WGN06-WPxx 1. Introduction The ATS Interfacility Data Communications (AIDC) application exchanges information between ATS Units (ATSUs) for support of critical Air Traffic Control (ATC) functions including: , Notification of flights approaching a Flight Information Region (FIR) boundary, , Coordination of boundary conditions and , Transfer of control and communications authority. 2. AIDC Variants in the Asia/Pacific Region There are two variants of AIDC defined for the Asia/Pacific Region. a) AFTN-based AIDC Protocol The latest version 2.0 as documented in the Asia/Pacific Regional Interface Control Document (ICD) for ATS Interfacility Data Communications (AIDC), Version 2.0 – September 2003 b) ATN-based AIDC Protocol This variant is under development based on Edition 3 of ICAO Doc 9705. It is not yet submitted for approval by Bangkok ICAO Regional Office 3. Key Differences in the AIDC Variants in the Asia/Pacific Region 3.1 Control Logic Control Logic is the rules governing the sequencing of messaging. The control logic for AFTN AIDC is in the ATC Application and is depicted in Figure 1. The control logic for ATN AIDC is in the Control Function of the Application Entity and is depicted in Figure 2. ACP - WGN06-WPxx Figure 1 – AFTN AIDC Control Logic Figure 2 – ATN AIDC Control Logic ACP - WGN06-WPxx 3.2 Message Format and Encoding AFTN AIDC messages are defined and encoded using standard AFTN text encoding while ATN AIDC messages have a distinct abstract syntax (ASN.1) and PER encoding rules. Figure 3 depicts the AFTN environment and Figure 4 depicts the ATN AIDC environment. AIDCAIDC AppApp Text Text MessagesMessages AFTN AFTN ServiceService AFTNAFTNSwitchSwitch Aeronautical Fixed Telecommunication NetworkAFTNSwitch(AFTN) Figure 3 - AFTN AIDC Architecture AIDCAIDC AppApp CFAIDCCF AIDCASEASN.1ASN.1ASE DefinedDefinedMessagesMessages ACSEACSE FB PresFB PresFB SessionFB Session TP4TP4CLNPCLNP ATNATNRTR RTR Aeronautical TelecommunicationSATNNetwork RTR(ATN) Figure 4 – ATN AIDC Architecture ACP - WGN06-WPxx 4. Current progress in the development of AIDC At the present, OPLINK panel has amended relevant information regarding AIDC at the OPLINKP1 meeting on September 2005. The new architecture of AIDC has not been incorporated in the ATN AIDC material in the technical manual. 5. Proposed Architecture – AFTN AIDC over ATN ICS Rather than implement the ATN AIDC Upper Layer Architecture, an AFTN AIDC-like architecture could be used. The concept is basically to run AFTN AIDC over the OSI Internet Communications Service (over TP4/CLNP). Figure 5 depicts this environment. AIDCAIDC AppA ppt 关于艾滋病ppt课件精益管理ppt下载地图下载ppt可编辑假如ppt教学课件下载triz基础知识ppt extText MessagesMessages TP4TP4 CLNPCLNP ATN ATNRTRRTR Aeronautical TelecommunicationS ATNNetworkRTR (ATN) Figure 5 - AFTN AIDC over ATN ICS The AIDC application in this case would be block oriented i.e. from the Transport Layer perspective it would look like an OSI upper layer application. The advantage of this approach is that it could readily operate in an IPS environment using RFC 1006. Thus if the Asia/Pacific region were to eventually migrate to an IPS or dual IPS/OSI infrastructure the application would be isolated from change. 5. Recommendation The working group is invited to comment on the proposed AIDC approach.