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Integrated Services Digital Network (ISDN) ETSI ETR 343 TECHNICAL March 1997 REPORT Source: ETSI TC-TE Reference: DTR/TE-02042 ICS: 33.020 Key words: ISDN, lower layer, protocol, satellite, terminal Integrated Services Digital Network (ISDN); Extended lower layer protocols; Definition of B and D Channel protocols with proposed Requirements List (RL) and profile specific Implementation Conformance Statement (ICS) ETSI European Telecommunications Standards Institute ETSI Secretariat Postal address: F-06921 Sophia Antipolis CEDEX - FRANCE Office address: 650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE X.400: c=fr, a=atlas, p=etsi, s=secretariat - Internet: [email protected] Tel.: +33 4 92 94 42 00 - Fax: +33 4 93 65 47 16 Copyright Notification: No part may be reproduced except as authorized by written permission. The copyright and the foregoing restriction extend to reproduction in all media. © European Telecommunications Standards Institute 1997. All rights reserved. Page 2 ETR 343: March 1997 Whilst every care has been taken in the preparation and publication of this document, errors in content, typographical or otherwise, may occur. If you have comments concerning its accuracy, please write to "ETSI Editing and Committee Support Dept." at the address shown on the title page. Page 3 ETR 343: March 1997 Contents Foreword .......................................................................................................................................................9 Introduction....................................................................................................................................................9 1 Scope ................................................................................................................................................11 2 References........................................................................................................................................12 3 Definitions and abbreviations ............................................................................................................14 3.1 Definitions ..........................................................................................................................14 3.2 Abbreviations .....................................................................................................................14 4 Conformance requirements...............................................................................................................15 4.1 Protocol stack ....................................................................................................................15 4.1.1 Supported protocols ......................................................................................15 4.1.2 Relationship between protocols ....................................................................16 4.2 Physical interface (layer 1).................................................................................................16 4.3 Link layer (layer 2): D-channel ...........................................................................................16 4.4 Link layer (layer 2): B-channel ...........................................................................................17 4.4.1 Protocol to be used .......................................................................................17 4.4.2 Octet alignment .............................................................................................17 4.4.2.1 Idle channel state.................................................................17 4.4.2.2 Active channel state - called terminal ..................................17 4.4.2.3 Active channel state - calling terminal .................................17 4.4.2.4 Recognition of octet alignment ............................................17 4.4.2.5 Return to idle channel state.................................................18 4.4.3 Terminal type selection .................................................................................18 4.4.3.1 General................................................................................18 4.4.3.2 Procedure at calling terminal ...............................................19 4.4.3.3 Procedure at called terminal................................................19 4.4.3.4 Selection by calling terminal ................................................19 4.4.4 Negotiation of essential data link parameters ...............................................19 4.4.4.1 During terminal type selection .............................................19 4.4.4.2 On receipt of XID frame with FIS = 82.................................20 4.4.5 Content and format of the XID frame ............................................................20 4.4.5.1 Format Identifier Subfield (FIS) ...........................................21 4.4.5.2 Data Link Subfield (DLS) .....................................................21 4.4.5.3 User Data Subfield (UDS) ...................................................21 4.4.6 Data link procedures .....................................................................................22 4.4.6.1 Mode of transmission ..........................................................22 4.4.6.2 Mode of operation................................................................22 4.4.6.3 Frame reject response.........................................................22 4.4.6.4 Single link procedure ...........................................................22 4.4.6.5 Procedure for addressing ....................................................23 4.4.6.6 Link set-up ...........................................................................23 4.4.6.7 Disconnected phase ............................................................23 4.4.6.8 Receiving an I-frame ...........................................................23 4.4.6.9 Unsolicited UA in information transfer phase ......................23 4.4.6.10 Procedure for link resetting..................................................23 4.4.6.11 Timer T1 ..............................................................................24 4.4.6.12 Parameter T2.......................................................................24 4.4.6.13 Timer T3 ..............................................................................24 4.4.6.14 Maximum number of transmissions N2...............................24 4.4.6.15 Maximum frame length N1 ..................................................24 4.4.6.16 Maximum number of outstanding I-frames k.......................24 Page 4 ETR 343: March 1997 4.5 Network layer (layer 3): D-channel.................................................................................... 25 4.5.1 Protocol to be used....................................................................................... 25 4.5.2 Terminal selection......................................................................................... 25 4.5.2.1 Compatibility information provided by the calling terminal .. 25 4.5.2.1.1 BC information element........................ 25 4.5.2.1.2 Low layer compatibility information element ................................................ 26 4.5.2.1.3 HLC information element ..................... 28 4.5.2.2 Compatibility checking by the called terminal ..................... 29 4.5.2.3 Low layer compatibility negotiation between users. ............ 30 4.5.2.4 Call acceptance conditions ................................................. 30 4.5.3 Interworking with other networks .................................................................. 31 4.5.3.1 Interworking with non-ISDNs............................................... 31 4.5.3.1.1 Outgoing calls....................................... 31 4.5.3.1.2 Incoming calls ...................................... 31 4.5.3.2 Interworking with private telecommunication networks....... 31 4.5.3.3 Interworking with a network having restricted bearer capability ............................................................................. 32 4.5.4 Use of ISDN supplementary services........................................................... 32 4.6 Network layer (layer 3): B-channel .................................................................................... 32 4.6.1 Protocol to be used....................................................................................... 32 4.6.2 Logical channels ........................................................................................... 32 4.6.3 Procedures for restart, virtual calls, data transfer, and reset........................ 32 4.6.3.1 Procedures to be used........................................................ 32 4.6.3.2 General packet format ........................................................ 32 4.6.3.3 Format of CALL REQUEST/INCOMING CALL packets ..... 33 4.6.4 Flow control parameters ............................................................................... 33 4.6.4.1 Flow control parameter negotiation..................................... 33 4.6.4.2 Maximum length of user data field...................................... 34 4.6.4.3 Window size and numbering of packets ............................. 34 4.6.5 Delivery confirmation bit ............................................................................... 34 4.6.6 Complete packet sequence .......................................................................... 35 4.6.7 Qualifier bit.................................................................................................... 35 4.6.8 Default throughput classes assignment.......................................................
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