Abstract

SUBJECT Addressing in L2R PDU's

Status
Published
Publication Date
30-Nov-2003
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
01-Dec-2003
Due Date
01-Dec-2003
Completion Date
01-Dec-2003

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SIST ETS 300 914 E4:2003

English language (24 pages)
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SIST ETS 300 914 E4:2003 is the Slovenian adoption of ETS 300 914 Edition 4, an ETSI European Telecommunications Standard for GSM Phase 2+. It specifies Terminal Adaptation Functions (TAF) for services using asynchronous bearer capabilities, so Mobile Termination (MT) equipment can attach asynchronous terminals and map them to GSM network procedures. In practice, it tells implementers how data, signalling, flow control, call setup, and L2R relay behave between the terminal side and the PLMN side.

What does SIST ETS 300 914 E4:2003 specify?

SIST ETS 300 914 E4:2003 specifies the interfaces and TAF integral to an MT for asynchronous terminals. Its scope covers V.14 procedures, V.21, V.22bis, V.23 and V.32 DTE/DCE interfaces, the I.420 S interface, and V.25bis and V.25ter signalling procedures.

The document is organised into clauses on scope and references, reference configuration, transparent services, non-transparent services, GSM 04.08 mapping, and dedicated PAD services. Annex A is normative and defines L2R functionality and the L2RCOP PDU rules. Annex B is informative and shows the 9-pin V.24 variant as an MT2 type.

AnnexWhat it covers
AL2R Functionality, including L2RCOP, status transfer, flow control, and break handling
BUse of the 9-pin version of V.24 as a MT2 type

The scope is focused on support for asynchronous bearer capabilities. It leaves out interface procedures that are not directly mappable to GSM 04.08, and it limits GSM 04.08 mapping to the call elements and messages that matter for these services.

What are the key requirements of SIST ETS 300 914 E4:2003?

SIST ETS 300 914 E4:2003 requires the MT TAF to translate the terminal-side interface into the GSM/PLMN side, not just pass bits through. That matters because the mobile equipment must handle rate adaptation, signalling, and control differences between a terminal and the radio network.

  • Clause 2 says the TAF must support manual and automatic call control for alternate speech/data, speech followed by data, and circuit switched services. It also covers conversion of interface characteristics, rate adaptation, signalling mapping, flow control, L2R, in-call modification, synchronisation, filtering, terminal compatibility checking, and split/combine handling for multislot data. In practice, implementers must support both terminal control and network control behavior.

  • Clause 3.1 to 3.3 requires transparent services to use the GSM 04.21 rate adaptation scheme and V.24-style signalling mapping, with interface signal levels conforming to V.28, IrDA IrPHY, PCMCIA 2.1, PC-Card 3.0, or later revisions. That means the physical and signalling layer on the terminal side must match one of the accepted electrical/interface families.

  • Clause 3.2.1 assigns S bits and the X bit for multislot transparent configurations, including substream numbering and frame synchronisation. This is what keeps parallel substreams aligned when more than one slot is used.

  • Clause 3.4 maps call establishment for autocalling, autoanswering, and manual operation. For S interface use, bearer capability requests must match the supported values, otherwise the call is rejected. This is the gate that decides whether the service can be set up at all.

  • Clause 4.3 to 4.4 requires flow control and buffering for non-transparent services so data is not lost when either side cannot accept more traffic. The text allows inband XON/XOFF and out-of-band control through CT106 or CT133, and it defines when flow control becomes active. In practice, this tells designers where to implement backpressure and how to keep buffers from overrunning.

  • Clause 4.6 and 4.7 require immediate handling of the BREAK condition and define data compression using ITU-T V.42bis with RLP-based error correction and negotiation. That matters for terminals that use compressed data, because break and reset behavior must keep the encoder and decoder in step.

  • Clause 5 and Clause 6 cover GSM 04.08 message mapping and Dedicated PAD services. For Dedicated PAD access, the TAF must supply a Private Number Plan, a Dedicated PAD type of number, and a short code coded according to GSM 09.05.

  • Annex A defines the L2RCOP PDU format and addressing rules in L2R PDUs. It is the part that explains how status octets, character data, flow control, and break indications are carried between the two L2R entities.

What terms does SIST ETS 300 914 E4:2003 define?

  • Terminal Adaptation Functions (TAF) - The functions in the MT that adapt asynchronous terminals to GSM/PLMN procedures.
  • Mobile Termination (MT) - The mobile-side unit that contains the TAF and interfaces the terminal to the network.
  • Layer 2 Relay (L2R) - The relay function used for non-transparent services to move data, status, and control information.
  • L2R Character Oriented Protocol (L2RCOP) - The PDU format used by L2R for character-oriented non-transparent protocols.
  • Radio Link Protocol (RLP) - The radio-link protocol whose version and frame type determine the L2RCOP PDU size and status handling.
  • TE2 - The asynchronous terminal equipment attached at the customer access side.
  • PLMN - The public land mobile network side that receives the mapped GSM procedures and bearer handling.

Who uses SIST ETS 300 914 E4:2003?

SIST ETS 300 914 E4:2003 is used by GSM mobile equipment engineers, terminal designers, and interworking-function developers who need to implement asynchronous data services. Test laboratories, conformance teams, and quality managers use it to check interface mapping, call setup behavior, flow control, and break handling. Buyers and integrators use it to confirm that a mobile termination supports the terminal interfaces and service types they need.

What changed in SIST ETS 300 914 E4:2003 from the previous edition?

SIST ETS 300 914 E4:2003 is identified as the fourth edition of ETS 300 914 and corresponds to GSM 07.02 version 5.4.1. The document history records earlier publication stages in 1996 and 1997 before this edition.

Which standards are used with SIST ETS 300 914 E4:2003?

ReferenceWhat it contributes
GSM 01.04Abbreviations and acronyms used in the document
GSM 02.02Supported bearer services in the GSM PLMN
GSM 03.10Connection types for transparent services
GSM 04.02Reference configuration for PLMN access
GSM 04.08 (ETS 300 940)Mobile radio interface layer 3 signalling
GSM 04.21 (ETS 300 945)Rate adaptation and status-bit use on the MS-BSS interface
GSM 07.01 (ETS 300 913)General TAF rules and L2R background
GSM 07.07 (ETS 300 916)AT command set for GSM mobile equipment
GSM 09.05PAD facility access and short code handling
V.24, V.25bis, V.25ter, V.42, V.42bis, V.110, I.420Interface, call control, error correction, compression, and ISDN-related bearer handling

What does the SIST ETS 300 914 E4:2003 document contain?

The document contains the reference configuration, transparent and non-transparent service procedures, signalling mappings, flow control rules, buffer behaviour, and dedicated PAD support. It also includes Table 2 for the minimum set of interchange circuits and Table 3 for minimum call setup commands and indications. Annex A adds the detailed L2RCOP PDU structure, status octet addressing, flow control, and destructive break handling, with figures that illustrate example PDUs. Annex B gives the 9-pin V.24 layout for an MT2 type.

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Frequently Asked Questions

SIST ETS 300 914 E4:2003 is a standard published by the Slovenian Institute for Standardization (SIST). Its full title is "Digital cellular telecommunications system (Phase 2+) (GSM); Terminal Adaptation Functions (TAF) for services using asynchronous bearer capabilities (GSM 07.02 version 5.4.1)". This standard covers: SUBJECT Addressing in L2R PDU's

SUBJECT Addressing in L2R PDU's

SIST ETS 300 914 E4:2003 is classified under the following ICS (International Classification for Standards) categories: 33.070.50 - Global System for Mobile Communication (GSM). The ICS classification helps identify the subject area and facilitates finding related standards.

SIST ETS 300 914 E4:2003 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.

Standards Content (Sample)


2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Digital cellular telecommunications system (Phase 2+) (GSM); Terminal Adaptation Functions (TAF) for services using asynchronous bearer capabilities (GSM 07.02 version 5.4.1)33.070.50Globalni sistem za mobilno telekomunikacijo (GSM)Global System for Mobile Communication (GSM)ICS:Ta slovenski standard je istoveten z:ETS 300 914 Edition 4SIST ETS 300 914 E4:2003en01-december-2003SIST ETS 300 914 E4:2003SLOVENSKI
STANDARD
EUROPEANETS 300 914TELECOMMUNICATIONMarch 1998STANDARDFourth EditionSource: SMGReference: RE/SMG-040702QR3ICS:33.020Key words:Digital cellular telecommunications system, Global System for Mobile communications (GSM)GLOBAL SYSTEM
FOR MOBILE COMMUNICATIONSRDigital cellular telecommunications system (Phase 2+);Terminal Adaptation Functions (TAF)for services using asynchronous bearer capabilities(GSM 07.02 version 5.4.1)ETSIEuropean Telecommunications Standards InstituteETSI SecretariatPostal address: F-06921 Sophia Antipolis CEDEX - FRANCEOffice address: 650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCEInternet: secretariat@etsi.fr - http://www.etsi.fr - http://www.etsi.orgTel.: +33 4 92 94 42 00 - Fax: +33 4 93 65 47 16Copyright Notification: No part may be reproduced except as authorized by written permission. The copyright and theforegoing restriction extend to reproduction in all media.© European Telecommunications Standards Institute 1998. All rights reserved.SIST ETS 300 914 E4:2003

Page 2ETS 300 914 (GSM 07.02 version 5.4.1): March 1998Whilst 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.SIST ETS 300 914 E4:2003

Page 3ETS 300 914 (GSM 07.02 version 5.4.1): March 1998ContentsForeword.51Scope.71.1Normative references.71.2Abbreviations.92Reference Configuration.92.1Customer Access Configuration.92.2Terminal Adaptation Function (TAF).93Terminal Adaptation Functions for transparent services.93.1Rate Adaptation.93.1.1Rate Adaptation - V series.103.1.2Rate Adaptation - S Interface (I.420).103.2Interchange Circuit Signalling Mapping.103.2.1Multislot configurations.103.2.2Channel coding TCH/F14.4.103.3Interface Signal Levels.103.4Call Establishment Signalling Mapping.103.4.1Autocalling/answering.103.4.2S Interface (I.420) Signalling Mapping.113.4.3Call Establishment Manual Operation - Utilizing Alternate Speech/Data orSpeech Followed By Data Capabilities.113.4.4Call Establishment Manual Operation - Utilizing the Unrestricted DigitalCapability.114Terminal Adaptation Functions for non transparent services.114.1Data Structure.114.1.1Data Structure on S Interface.114.1.2Data Structure on R Interface.114.1.3Data Structure Provided by the L2R Function to the RLP Function.114.2Signalling Mapping.114.3Flow Control.124.3.1Conditions Requiring Flow Control towards the Network.124.3.2Conditions Requiring Flow Control towards TE2.124.3.3Local Flow Control.124.3.4Character Orientated Protocol with No Flow Control.134.4Buffers.134.4.1TX Buffers.134.4.2RX Buffers.134.5Bit Transparency.134.6Transportation of "BREAK" condition.134.7Data Compression.135Terminal interfacing to GSM 04.08 Mapping.155.1Mobile Originated Calls.165.2Mobile Terminated Calls.166Functionality for the Support of Dedicated PAD Services.17Annex A (Normative):L2R Functionality.18A.1Introduction.18A.2The L2RCOP.18SIST ETS 300 914 E4:2003

Page 4ETS 300 914 (GSM 07.02 version 5.4.1): March 1998A.3Use of the L2RCOP.21A.3.1Radio Link Connection Control.21A.3.2Data Transfer.21A.3.3Status Transfer.21A.3.4Flow Control.21A.3.5Break.21A.3.5.1Normal Realization.21A.3.5.2Realization in case of Data Compression is used.21Annex B (Informative):Use of the 9 pin version of V.24 as a MT2 type.23History.24SIST ETS 300 914 E4:2003

Page 5ETS 300 914 (GSM 07.02 version 5.4.1): March 1998ForewordThis fourth edition European Telecommunications Standard (ETS) has been produced by the SpecialMobile Group (SMG) of the European Telecommunications Standards Institute (ETSI).This ETS defines the interfaces and Terminal Adaptation Functions (TAF) integral to a Mobile Termination(MT) which enables the attachment of asynchronous terminals to a MT within the digital cellulartelecommunications system (Phase 2+).The contents of this ETS is subject to continuing work within SMG and may change following formal SMGapproval. Should SMG modify the contents of this ETS, it will be resubmitted for OAP by ETSI with anidentifying change of release date and an increase in version number as follows:Version 5.x.ywhere:ythe third digit is incremented when editorial only changes have been incorporated in thespecification;xthe second digit is incremented for all other types of changes, i.e. technical enhancements,corrections, updates, etc.The specification from which this ETS has been derived was originally based on CEPT documentation,hence the presentation of this ETS may not be entirely in accordance with the ETSI drafting rules.Transposition datesDate of adoption of this ETS:3 April 1998Date of latest announcement of this ETS (doa):30 June 1998Date of latest publication of new National Standardor endorsement of this ETS (dop/e):31 December 1998Date of withdrawal of any conflicting National Standard (dow):31 December 1998SIST ETS 300 914 E4:2003

Page 6ETS 300 914 (GSM 07.02 version 5.4.1): March 1998Blank pageSIST ETS 300 914 E4:2003

Page 7ETS 300 914 (GSM 07.02 version 5.4.1): March 19981ScopeThis European Telecommunications Standard (ETS) defines the interfaces and Terminal AdaptationFunctions (TAF) integral to a Mobile Termination (MT) which enables the attachment of asynchronousterminals to a MT (see GSM 04.02 [4]). The general aspects of Terminal Adaptation Functions arecontained in GSM 07.01 (ETS 300 913) [7]. This ETS covers support of these services for the followinginterfaces and procedures:(i)V.14 procedures(ii)V.21 DTE/DCE interface(iii)V.22bis DTE/DCE interface(iv)V.23 DTE/DCE interface(v)V.32 DTE/DCE procedures(vi)I.420 S interface(vii)V.25bis signalling procedures(viii)V.25ter signalling proceduresThe asynchronous data rates between the MT and the TE2 are defined in GSM 02.02 (ETS 300 904) [2].1.1Normative referencesThis ETS incorporates by dated and undated reference, provisions from other publications. Thesenormative references are cited at the appropriate places in the text and the publications are listedhereafter. For dated references, subsequent amendments to or revisions of any of these publicationsapply to this ETS only when incorporated in it by amendment or revision. For undated references, thelatest edition of the publication referred to applies.[1]GSM 01.04 (ETR 350): "Digital cellular telecommunication system (Phase 2+);Abbreviations and acronyms".[2]GSM 02.02 (ETS 300 904): "Digital cellular telecommunication system(Phase 2+); Bearer Services (BS) supported by a GSM Public Land MobileNetwork (PLMN)".[3]GSM 03.10: "Digital cellular telecommunication system (Phase 2+); GSM PublicLand Mobile Network (PLMN) connection types".[4]GSM 04.02: "Digital cellular telecommunication system (Phase 2+); GSM PublicLand Mobile Network (PLMN) access reference configuration".[5]GSM 04.08 (ETS 300 940): "Digital cellular telecommunication system(Phase 2+); Mobile radio interface layer 3 specification".[6]GSM 04.21 (ETS 300 945): "Digital cellular telecommunication system; Rateadaption on the Mobile Station - Base Station System (MS - BSS) interface ".[7]GSM 07.01 (ETS 300 913): "Digital cellular telecommunication system(Phase 2+); General on Terminal Adaptation Functions (TAF) for MobileStations (MS)".[8]GSM 07.07 (ETS 300 916): "Digital cellular telecommunication system(Phase 2+); AT command set for GSM Mobile Equipment (ME)[9]GSM 09.05: "Digital cellular telecommunication system; Interworking betweenthe Public Land Mobile Network (PLMN) and the Packet Switched Public DataNetwork (PSPDN) for Packet Assembly/Disassembly (PAD) facility access".[10]CCITT Recommendation V.4: "General structure of signals of internationalalphabet No.5 code for character oriented data transmission over publictelephone networks".SIST ETS 300 914 E4:2003

Page 8ETS 300 914 (GSM 07.02 version 5.4.1): March 1998[11]CCITT Recommendation V.25 bis (1988): Blue book, Volume VIII, FascicleVIII.1 "Automatic Calling and/or Answering Equipment on the General SwitchedTelephone Network (GSTN) using the 100-Series Interchange Circuits". [12]ITU-T Recommendation V.25 ter: "Serial asynchronous automatic dialling andcontrol".[13]CCITT Recommendation V.110: "Support of data terminal equipments (DTEs)with V-Series interfaces by an integrated services digital network".[14]CCITT Recommendation V.24 (1988): Blue book, Volume VIII, Fascicle VIII.1"List of definitions for interchange circuits between data terminal equipment(DTE) and data circuit-terminating equipment".[15]CCITT Recommendation V.21 (1988): Blue book, Volume VIII, Fascicle VIII.1"300 bits per second duplex modem standardized for use in the generalswitched telephone network".[16]CCITT Recommendation V.14 (1988): Blue book, Volume VIII, Fascicle VIII.1"Transmission of start-stop characters over synchronous bearer channels".[17]CCITT Recommendation V.22bis (1988): Blue book, Volume VIII, Fascicle VIII.1"2400 bits per second duplex modem using the frequency division techniquestandardized for use on the general".[18]CCITT Recommendation V.23 (1988): Blue book, Volume VIII, Fascicle VIII.1"600/1200-baud modem standardized for use in the general switched telephonenetwork".[19]CCITT Recommendation V.32 (1988): Blue book, Volume VIII, Fascicle VIII.1 "Afamily of 2-wire, duplex modems operating at data signalling rates of up to9600 bit/s for use in the general switched telephone network and on leasedtelephone-type circuits".[20]CCITT Recommendation V.42 (1988): Blue book, Volume VIII, Fascicle VIII.1"error-correcting procedures for DCEs using asynchronous-to-synchronousconversion".[21]ITU-T Recommendation V.42 bis: "Data compression procedures for data circuitterminating equipment (DCE) using error correction procedures[22]CCITT Recommendation X.28: "DTE/DCE interface for a start-stop mode dataterminal equipment accessing the packet assembly/disassembly facility (PAD) ina public data network situated in the same country".[23]Recommendations I.310-I.470 (Study Group XVIII): Blue book, Volume III,Fascicle III.8, Overall network aspects and functions, ISDN user-networkinterfaces.[24]CCITT Recommendation I.420: Blue book, Volume III, Fascicle III.8 "Basicuser-network interface".[25]Personal Computer Memory Card Association: "PCMCIA 2.1 or PC-Card 3.0electrical specification or later revisions".[26]Infrared Data Association IrDA "IrPHY Physical layer signalling standard".[27]TIA-617: "Data Transmission Systems and Equipment - In-Band DCE Control".[28]GSM 02.34: “Digital cellular telecommunications system (Phase 2+); HighSpeed Circuit Switched Data (HSCSD) - Stage 1”SIST ETS 300 914 E4:2003

Page 9ETS 300 914 (GSM 07.02 version 5.4.1): March 1998[29]GSM 03.34 (TS 101 038): “Digital cellular telecommunications system(Phase 2+); High Speed Circuit Switched Data (HSCSD) - Stage 2 ServiceDescription”1.2AbbreviationsAbbreviations used in this ETS are listed in GSM 01.04 (ETR 350) [1].2Reference ConfigurationGSM 07.01 (ETS 300 913) [7] and GSM 04.02 [4] describe the basic reference configurations.2.1Customer Access ConfigurationThis configuration is as shown in figure 1 of GSM 04.02 [4]. This ETS specifically refers to the MobileTerminations (MTs) which support terminals of the type TE1 and TE2 with asynchronous capabilities. TheTAF is functionally a part of an MT1, MT2 or MT0 with an integral asynchronous data capability.2.2Terminal Adaptation Function (TAF)The TAF provides facilities to allow manual or automatic call control functions associated with alternatespeech/data, speech followed by data and circuit switched services. The following functions are alsoincluded:-Conversion of electrical, mechanical, functional and procedural characteristics of the V series andISDN type interfaces to those required by the PLMN-Bit rate adaptation of the V series data signalling rates and the ISDN 64 kbit/s to that provided in thePLMN-The mapping functions necessary to convert automatic calling and/or automatic answeringprocedures of recommendation V.25 bis or V.25 ter and parameters for asynchronous operation-The mapping functions necessary to convert S interface signalling to the PLMN Dm channelsignalling-Flow control (in some cases resulting in non-transparency of data as described in section 4.3)-Layer 2 Relaying (see annex A)-In-call modification function-Synchronization procedure, which means the task of synchronizing the entry to and the exit fromthe data transfer phase between two user terminals. This is described in GSM 07.01(ETS 300 913) [7]-Filtering of channel control information as described in GSM 07.01 (ETS 300 913) [7]-Terminal compatibility checking- Splitting and combining of the data flow in case of multislot data configurations3Terminal Adaptation Functions for transparent servicesGSM 03.10 [3] refers to the connection types supporting the transparent services.3.1Rate AdaptationGSM 04.21 (ETS 300 945) [6] describes the rate adaptation scheme to be utilized over the Base Station(BS) to Mobile Station (MS) link. GSM 03.10 [3] refers to the rate adaptation elements to be provided inthe MS.SIST ETS 300 914 E4:2003

Page 10ETS 300 914 (GSM 07.02 version 5.4.1): March 19983.1.1Rate Adaptation - V seriesThis is provided as indicated in GSM 04.21 (ETS 300 945) [6].3.1.2Rate Adaptation - S Interface (I.420)The ISDN rate adapted frame format is modified to the PLMN rate adapted format as indicated inGSM 04.21 (ETS 300 945) [6].3.2Interchange Circuit Signalling MappingThe interchange circuit signalling mapping at the interface between the TE2 and the MT shall conform toCCITT Recommendation V.24 [14]. The signals required at this interface are shown in table 2.GSM 04.21 (ETS 300 945) [6] refers to the frame structure and identifies the use of the status bits for thecarriage of signalling information.Status bits (S1,S3,S4,S6,S8,S9 and X):The bits S and X are used to convey channel control information associated with the data bits in the datatransfer stage as shown below. The S bits are put into two groups SA and SB to carry the condition of twointerchange circuits. The X bit is used to carry the condition of circuit 106.The mechanism for proper assignment of the control information from the transmitting signal rate adapterinterface via these bits to the receiving signal rate adapter interface is shown below in table 1.For the S and X bits, a ZERO corresponds with the ON condition, a ONE with the OFF condition.108S1,S3,S6,S8 = SA107105S4,S9 = SB109106X106TE --- > IWFIWF ---- > TE3.2.1 Multislot configurationsIn transparent multislot configurations status bits S1, S3 and the X-bit between the D12 and D13 - in theITU-T V.110 80-bit intermediate rate frame - are used for transferring substream numbering information.The S4-bit is used for frame synchronization between the parallel substreams (ref GSM 04.21).3.2.2 Channel coding TCH/F14.4For information on the mapping of the interchange circuit signalling bits as specified
in GSM 04.21.3.3Interface Signal LevelsThe signal levels at the interface between the TE2 and the MT shall conform to CCITT V.28, or to IrDAIrPHY physical signalling standard specification, or to PCMCIA 2.1, or to PC-Card 3.0 electricalspecification or to later revisions.3.4Call Establishment Signalling Mapping3.4.1Autocalling/answeringThe mapping of the V.25 bis [11] procedures to the messages of the PLMN signalling in GSM 04.08(ETS 300 940) [5] is defined in section 5.a)Auto CallingThis procedure is provided according to V.25 bis [11] using only 108/2.SIST ETS 300 914 E4:2003

Page 11ETS 300 914 (GSM 07.02 version 5.4.1): March 1998A subset of V.25 bis is shown in table 3. This subset gives minimum level of control and indication.During the call establishment phase, i.e. after signalling, call tone according to V.25 bis shall begenerated in the IWF.An alternative to CCITT V.25bis [11] is to use the ITU-T V.25 ter dial command as specified inGSM 07.07 (ETS 300 916) [8].b)Auto AnswerThis procedure is provided according to V.25bis [11] or to V.25 ter [12].3.4.2S Interface (I.420) Signalling MappingThe mapping of Q.931 signalling to GSM 04.08 (ETS 300 940) [5] signalling requires the inclusion, by theMT, of PLMN specific elements (e.g. transparent or not, half/full rate channel). For asynchronous Bearerservices, requests for bearer capabilities not listed in table 4 (or where the "Users information layer 1protocol" element does not indicate V.110) will result in
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