SIST ETS 300 976 E9:2003

Digital cellular telecommunications system (Phase 2+) (GSM); General requirements on interworking between the Public Land Mobile Network (PLMN) and the Integrated Services Digital Network (ISDN) or Public Switched Telephone Network (PSTN) (GSM 09.07 version 5.10.1 Release 1996)

CR #N6

Digitalni celični telekomunikacijski sistem (faza 2+) – Splošne zahteve za medsebojno delovanje javnega kopenskega mobilnega omrežja (PLMN) in digitalnega omrežja z integriranimi storitvami (ISDN) ali javnega komutiranega telefonskega omrežja (PSTN) (GSM 09.07, različica 5.10.1, izdaja 1996)

General Information

• Status: Published
• Publication Date: 30-Nov-2003
• ICS: 33.040.35 - Telephone networks
• ICS: 33.070.50 - Global System for Mobile Communication (GSM)
• ICS: 33.080 - Integrated Services Digital Network (ISDN)
• Technical Committee: SS EIT - Technical Board for the electrotechnical, information technology and telecommunications fields
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-Dec-2003
• Due Date: 01-Dec-2003
• Completion Date: 01-Dec-2003
• Ref Project: ETSI ETS 300 976 ed.9 (2000-06) - Digital cellular telecommunications system (Phase 2+) (GSM); General requirements on interworking between the Public Land Mobile Network (PLMN) and the Integrated Services Digital Network (ISDN) or Public Switched Telephone Network (PSTN) (GSM 09.07 version 5.10.1 Release 1996)

Standards Content (Sample)

SLOVENSKI STANDARD
SIST ETS 300 976 E9:2003
01-december-2003
'LJLWDOQLFHOLþQLWHOHNRPXQLNDFLMVNLVLVWHPID]D±6SORãQH]DKWHYH]D
PHGVHERMQRGHORYDQMHMDYQHJDNRSHQVNHJDPRELOQHJDRPUHåMD3/01LQ
GLJLWDOQHJDRPUHåMD]LQWHJULUDQLPLVWRULWYDPL,6'1DOLMDYQHJDNRPXWLUDQHJD
WHOHIRQVNHJDRPUHåMD3671*60UD]OLþLFDL]GDMD
Digital cellular telecommunications system (Phase 2+) (GSM); General requirements on
interworking between the Public Land Mobile Network (PLMN) and the Integrated
Services Digital Network (ISDN) or Public Switched Telephone Network (PSTN) (GSM
09.07 version 5.10.1 Release 1996)
Ta slovenski standard je istoveten z: ETS 300 976 Edition 9
ICS:
33.040.35 Telefonska omrežja Telephone networks
33.070.50 Globalni sistem za mobilno Global System for Mobile
telekomunikacijo (GSM) Communication (GSM)
33.080 Digitalno omrežje z Integrated Services Digital
integriranimi storitvami Network (ISDN)
(ISDN)
SIST ETS 300 976 E9:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST ETS 300 976 E9:2003

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SIST ETS 300 976 E9:2003
EUROPEAN ETS 300 976
TELECOMMUNICATION June 2000
STANDARD Ninth Edition
Source: SMG Reference: RE/SMG-040907QR10
ICS: 33.020
Key words: Digital cellular telecommunications system, Global System for Mobile communications (GSM)
R
GLOBAL SYSTEM FOR
MOBILE COMMUNICATIONS
Digital cellular telecommunications system (Phase 2+);
General requirements on interworking between the Public Land
Mobile Network (PLMN) and the Integrated Services Digital
Network (ISDN) or Public Switched Telephone Network (PSTN)
(GSM 09.07 version 5.10.1 Release 1996)
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
Internet: [e-mail] - http://www.etsi.org
Tel.:[phone]- Fax:[phone]
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 2000. All rights reserved.

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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 Standards Making Support Dept." at the address shown on the title page.

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Contents
Intellectual Property Rights.7
Foreword.7
1 Scope .9
2 Normative references.9
3 Definitions and abbreviations .11
3.1 Definitions .11
3.2 Abbreviations .12
4 Introduction.13
5 Not used .13
6 Network Characteristics .14
6.1 Key Characteristics of Networks Concerned .14
6.1.1 Characteristics of PLMNs.14
6.1.2 Characteristics of PSTNs .14
6.1.3 Characteristics of ISDN .15
7 Interworking classifications.15
7.1 Service interworking.15
7.2 Network interworking .15
7.3 Signalling interworking .17
7.4 Numbering .17
7.5 Supplementary service interworking .17
8 Compatibility and subscription checking .18
9 Interworking to PSTN .18
9.1 Speech Calls.18
9.1.1 Interworking indications to PLMN terminal .18
9.1.2 Transmission aspects.18
9.1.3 Generation of In-band Tones and Announcements (PLMN-PSTN).18
9.2 Data Calls.18
9.2.1 Network interworking mobile originated .19
9.2.1.1 Selection of interworking function.19
9.2.1.2 Modem Selection .20
9.2.1.3 DTE/Modem interface (Filtering) .20
9.2.1.4 Mapping of BC-IE from GSM 04.08 to ISUP (or other).21
9.2.2 Network Interworking Mobile terminated PSTN Originated.21
9.2.3 Transparent service support.26
9.2.3.1 Not used .26
9.2.3.2 Rate adaptation process in MSC/IWF .26
9.2.3.3 Mapping of signalling MS/MSC/IWF to modem interface
requirements.26
9.2.3.4 Establishment of end-to-end terminal synchronizations .27
9.2.3.5 Network Independent Clocking (NIC) .28
9.2.4 Non-transparent service support .28
9.2.4.1 MSC-IWF Rate adaptation scheme.29
9.2.4.2 Protocol layer structure in the MSC/IWF .29
9.2.4.3 Re-constitution of user data.29
9.2.4.4 Layer 2 relay functionality .29
9.2.4.5 In band signalling mapping flow control.29

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9.2.4.5.1 Conditions requiring flow control
towards the fixed network. 30
9.2.4.5.2 Conditions requiring flow control
towards the MS . 30
9.2.4.6 Data buffers. 30
9.2.4.6.1 Transmit buffers (towards MS). 30
9.2.4.6.2 Receive buffers (from MS) . 30
9.2.4.7 Transportation of the Break condition . 30
9.2.4.8 In band signalling mapping modem status information. 30
9.2.4.9 Support of out-band flow control . 31
9.2.4.10 Establishment of end-to-end terminal synchronizations. 31
9.2.4.11 Data compression . 32
9.3 Interworking Alternate Speech / Data Calls. 32
9.3.1 Alternate Speech/Data Interworking . 32
9.3.1.1 General . 32
9.3.1.2 Mobile originated PSTN terminated calls . 32
9.3.1.3 PSTN originated mobile terminated calls. 32
9.3.2 Speech followed by data interworking . 33
9.3.2.1 General . 33
10 Interworking to the ISDN. 33
10.1 Speech Calls . 34
10.2 Data Calls. 34
10.2.1 Network interworking mobile originated. 34
10.2.1.1 Circuit switched calls. 34
10.2.1.2 Packet calls . 34
10.2.2 Network interworking mobile terminated. 34
10.2.2.1 Circuit switched calls. 53
10.2.2.2 Packet calls . 53
10.2.3 Transparent service support (see GSM 03.10). 53
10.2.3.1 MSC - IWF rate adaptation scheme. 53
10.2.3.2 Rate adaptation process in MSC/IWF. 54
10.2.3.3 Mapping of signalling MS/MSC/IWF to modem interface
requirements . 54
10.2.3.4 Establishment of end-to-end terminal synchronizations. 54
10.2.3.5 Network independent Clocking (NIC). 55
10.2.4 Non-transparent service support (See GSM 03.10) . 55
10.2.4.1 MSC - IWF Rate adaptation scheme . 55
10.2.4.2 Protocol layer structure in the MSC/IWF. 55
10.2.4.3 Re-constitution of user data . 56
10.2.4.4 Layer 2 relay functionality. 56
10.2.4.5 In band signalling mapping flow control . 56
10.2.4.5.1 Conditions requiring flow control - if
flow control is provided -towards the
fixed network . 57
10.2.4.5.2 Conditions requiring flow control
towards the MS . 57
10.2.4.6 Data buffers. 57
10.2.4.6.1 Transmit buffers (towards MS). 57
10.2.4.6.2 Receive buffers (from MS) . 57
10.2.4.7 BREAK Indication. 58
10.2.4.8 Signalling mapping modem status information or in band
rate adapted frame information. 58
10.2.4.9 Support of out-band flow control . 58
10.2.4.10 Synchronizations . 58
10.2.4.10.1 V.110 and V.120 Frame
synchronizations. 58
10.2.4.10.2 RLP Frame start indication. 58
10.2.4.10.3 L2R Frame synchronizations. 58
10.2.4.10.4 Establishment of end-to-end terminal
synchronizations. 58
10.2.4.11 Data compression . 59
10.2.4.12 Additional aspects of V.120 Interworking. 59

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10.2.4.12.1 V.120 Signalling parameters.60
10.2.4.12.2 V.120 Protocol parameters .60
10.2.4.12.3 Data compression on the ISDN .60
10.2.4.13 Interworking with restricted 64 kbit/s networks .60
10.2.4.13.1 Rate adaptation.60
10.2.4.13.2 MSC - ISDN signalling .60
10.2.5 DTE/Modem interface (Filtering) .60
10.3 Interworking Alternate speech data calls .62
10.3.1 Alternate speech data bearer interworking.62
10.3.1.1 General .62
10.3.1.2 Mobile originated ISDN terminated.62
10.3.1.3 ISDN originated mobile terminated.62
10.3.2 Speech followed by data interworking .63
10.3.2.1 General .63
11 Frame Synchronization.63
11.1 Initial frame synchronization.63
11.2 Action on loss of frame synchronization for non transparent services.63
11.3 Action on loss of frame synchronization for transparent services.63
Annex A (informative): SDLs.65
Annex B (informative): Change history.67
History.68

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Intellectual Property Rights
IPRs essential or potentially essential to the present document may have been declared to ETSI. The
information pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-
members, and can be found in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or
potentially Essential, IPRs notified to ETSI in respect of ETSI standards", which is available from the ETSI
Secretariat. Latest updates are available on the ETSI Web server (http://www.etsi.org/ipr).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI.
No guarantee can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the
updates on the ETSI Web server) which are, or may be, or may become, essential to the present
document.
Foreword
This European Telecommunication Standard (ETS) has been produced by the Special Mobile Group
(SMG) Technical Committee of the European Telecommunications Standards Institute (ETSI).
This ETS identifies the Mobile-services Switching Centre/Interworking functions (MSC/IWFs) and
requirements to support interworking between:
i) PLMN and PSTN;
ii) PLMN and ISDN.
within the digital cellular telecommunications system.
The contents of this ETS are subject to continuing work within SMG and may change following formal
SMG approval. Should SMG modify the contents of this ETS, it will then be resubmitted for OAP by ETSI
with an identifying change of release date and an increase in version number as follows:
Version 5.x.y
where:
5 indicates GSM Phase 2+ Release 1996.
x the second digit is incremented for all changes of substance, i.e. technical enhancements,
corrections, updates, etc.
y the third digit is incremented when editorial only changes have been incorporated in the
specification.
Transposition dates
Date of adoption: 19 May 2000
Date of latest announcement of this ETS (doa): 31 August 2000
Date of latest publication of new National Standard
or endorsement of this ETS (dop/e): 28 February 2001
Date of withdrawal of any conflicting National Standard (dow): 28 February 2001

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1 Scope
This European Telecommunication Standard (ETS) identifies the Mobile-services Switching
Centre/Interworking Functions (MSC/IWFs) and requirements to support interworking between:
a) PLMN and PSTN
b) PLMN and ISDN
It is not possible to treat ISDN and PSTN as one type of network, even when both ISDN and PSTN
subscribers are served by the same exchange because of the limitations of the PSTN subscribers access
i.e. analogue connection without D-channel signalling.
Within this ETS, the requirements for voice and non-voice (data) calls are considered separately.
2 Normative references
This ETS incorporates by dated and undated reference, provisions from other publications. These
normative references are cited at the appropriate places in the text and the publications are listed
hereafter. For dated references, subsequent amendments to or revisions of any of these publications
apply to this ETS only when incorporated in it by amendment or revision. For undated references, the
latest edition of the publication referred to applies.
[1] CCITT Recommendation G.711: "Pulse code modulation (PCM) of voice
frequencies".
[2] CCITT Recommendation I.460: "Multiplexing, rate adaption and support of
existing interfaces".
[3] CCITT Recommendation V.25: "Automatic answering equipment and/or parallel
automatic calling equipment on the general switched telephone network
including procedures for disabling of echo control devices for both manually and
automatically established calls".
[4] CCITT Recommendation V.42bis: "Data Compression for Data Circuit
Terminating Equipment (DCE) using Error Correction Procedures"
[5] CCITT Recommendation V.110: "Support of data terminal equipments (DTEs)
with V-Series interfaces by an integrated services digital network".
[6] ETS 300 102-1 Edition 1 (1990): "Integrated Services Digital Network (ISDN);
User-network interface layer 3 Specifications for basic call control".
[7] ETS 300 121: "Integrated Services Digital Network (ISDN); Application of the
ISDN User Part (ISUP) of CCITT Signalling System No.7 for international ISDN
interconnections (ISUP version 1)".
[8] GSM 01.04 (ETR 350): "Digital cellular telecommunication system (Phase 2+);
Abbreviations and acronyms".
[9] GSM 02.01: "Digital cellular telecommunication system (Phase 2+); Principles of
telecommunication services supported by a GSM Public Land Mobile Network
(PLMN)".
[10] GSM 02.02 (ETS 300 904): "Digital cellular telecommunications system
(Phase 2+); Bearer Services (BS) supported by a GSM Public Land Mobile
Network (PLMN)".
[11] GSM 02.03 (ETS 300 905): "Digital cellular telecommunications system
(Phase 2+); Teleservices supported by a GSM Public Land Mobile Network
(PLMN)".

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[12] GSM 02.04 (ETS 300 918): "Digital cellular telecommunications system
(Phase 2+); General on supplementary services".
[13] GSM 02.81: "Digital cellular telecommunication system (Phase 2+); Line
identification supplementary services - Stage 1".
[14] GSM 02.82: "Digital cellular telecommunication system (Phase 2+); Call
Forwarding (CF) supplementary services - Stage 1".
[15] GSM 02.83: "Digital cellular telecommunication system (Phase 2+); Call Waiting
(CW) and Call Hold (HOLD) supplementary services - Stage 1".
[16] GSM 02.84: "Digital cellular telecommunication system (Phase 2+); MultiParty
(MPTY) supplementary services - Stage 1".
[17] GSM 02.85: "Digital cellular telecommunication system (Phase 2+); Closed User
Group (CUG) supplementary services - Stage 1".
[18] GSM 02.86: "Digital cellular telecommunication system (Phase 2+); Advice of
charge (AoC) supplementary services - Stage 1".
[19] GSM 02.88: "Digital cellular telecommunication system (Phase 2+); Call Barring
(CB) supplementary services - Stage 1".
[20] GSM 03.03 (ETS 300 927): "Digital cellular telecommunications system
(Phase 2+); Numbering, addressing and identification".
[21] GSM 03.08: "Digital cellular telecommunication system (Phase 2+);
Organization of subscriber data".
[22] GSM 03.11 (ETS 300 928): "Digital cellular telecommunications system
(Phase 2+); Technical realization of supplementary services".
[23] GSM 03.45 (ETS 300 931): "Digital cellular telecommunications system
(Phase 2+); Technical realization of facsimile group 3 transparent".
[24] GSM 03.46: "Digital cellular telecommunication system (Phase 2+); Technical
realization of facsimile group 3 non-transparent".
[25] GSM 03.50 (ETS 300 903): "Digital cellular telecommunications system
(Phase 2+); Transmission planning aspects of the speech service in the GSM
Public Land Mobile Network (PLMN) system".
[26] GSM 04.08 (ETS 300 940): "Digital cellular telecommunications system
(Phase 2+); Mobile radio interface layer 3 specification".
[27] GSM 04.21 (ETS 300 945): "Digital cellular telecommunications system
(Phase 2+); Rate adaption on the Mobile Station - Base Station System (MS -
BSS) interface".
[28] GSM 04.22 (ETS 300 946): "Digital cellular telecommunications system
(Phase 2+); Radio Link Protocol (RLP) for data and telematic services on the
Mobile Station - Base Station System (MS - BSS) interface and the Base Station
System - Mobile-services Switching Centre (BSS - MSC) interface".
[29] GSM 07.01 (ETS 300 913): "Digital cellular telecommunications system
(Phase 2+); General on Terminal Adaptation Functions (TAF) for Mobile
Stations (MS)".
[30] GSM 07.02 (ETS 300 914): "Digital cellular telecommunications system
(Phase 2+); Terminal Adaptation Functions (TAF) for services using
asynchronous bearer capabilities".

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[31] GSM 07.03 (ETS 300 915): "Digital cellular telecommunications system
(Phase 2+); Terminal Adaptation Functions (TAF) for services using
synchronous bearer capabilities".
[32] GSM 07.05: "Digital cellular telecommunication system (Phase 2+); Use of Data
Terminal Equipment - Data Circuit terminating Equipment (DTE - DCE) interface
for Short Message Service (SMS) and Cell Broadcast Service (CBS)".
[35] GSM 08.20: "Digital cellular telecommunication system (Phase 2+); Rate
adaption on the Base Station System - Mobile-services Switching Centre (BSS -
MSC) interface".
[36] GSM 08.60 (ETS 300 737): "Digital cellular telecommunications system
(Phase 2+); Inband control of remote transcoders and rate adaptors for
Enhanced Full Rate (EFR) and full rate traffic channels".
[37] GSM 09.02 (ETS 300 974): "Digital cellular telecommunications system
(Phase 2+); Mobile Application Part (MAP) specification".
[38] GSM 09.03: "Digital cellular telecommunication system (Phase 2+); Signalling
requirements on interworking between the Integrated Services Digital Network
(ISDN) or Public Switched Telephone Network (PSTN) and the Public Land
Mobile Network (PLMN)".
[39] GSM 09.05: "Digital cellular telecommunication system (Phase 2+); Interworking
between the Public Land Mobile Network (PLMN) and the Packet Switched
Public Data Network (PSPDN) for Packet Assembly/Disassembly facility (PAD)
access".
[40] GSM 09.06 (ETS 300 975): "Digital cellular telecommunications system
(Phase 2+); Interworking between a Public Land Mobile Network (PLMN) and a
Packet Switched Public Data Network/Integrated Services Digital Network
(PSPDN/ISDN) for the support of packet switched data transmission services".
[41] CCITT Recommendation V.120: "Support by an ISDN of data terminal
equipment with V-Series type interfaces with provision for statistical
multiplexing".
[42] ETR 018: "Integrated Services Digital Network (ISDN); Application of the Bearer
Capability (BC), High Layer Compatibility (HLC) and Low Layer Compatibility
(LLC) information elements by terminals supporting ISDN services".
[43] CCITT Recommendation I.464: "Multiplexing, rate adaption and support of
existing interfaces for restricted 64 kbit/s transfer capability".
[44] CCITT Recommendation Q.922 (1992): "DSS 1 Data link layer: ISDN data link
layer specification for frame mode bearer services"
NOTE: As regards ETS 300 102-1 [6], the first edition of this ETS from 1990 shall be used,
with one exception: the encoding of the field modem type in the ISDN BC-IE shall be
handled as specified in table 6A and 6B.
3 Definitions and abbreviations
3.1 Definitions
Use is made of the following terms within this ETS. These terms refer to information requirements
necessary to support interworking functions, some of these terms will be identifiable with their use in other
GSM specifications.
bearer capability information: Specific information defining the lower layer characteristics required
within the network.

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low layer compatibility information: Information defining the lower layer characteristics of the terminal.
high layer compatibility information: Information defining the higher layer characteristics of the
terminal.
compatibility information: This term subsumes the entirety of Bearer Capability, Low Layer
Compatibility, High Layer Compatibility, Progress Indicator and Address Information conveyed out-of-band
prior to call establishment for the support of compatibility checking and terminal/function/service selection
at the ISDN-type user-network interface.
protocol identifier: Information defining the specific protocols utilized for the support of data transfer by a
terminal.
progress indicator: Information supplied to indicate to the terminal that network interworking has taken
place.
out-of-band parameter exchange: Information exchanged via an associated or non-associated
signalling link e.g. SS No 7.
PSTN: Subscriber to network interface supports only analogue terminals.
ISDN: Subscriber to network interface supports digital or analogue terminals, plus a standardized user to
network associated signalling system and a standardized internetwork signalling system.
autobauding type 1: This information element value may be contained in the setup or call confirm
messages from the MS in association with a non transparent data service. This implies that the MSC/IWF
may select any speed and modem type according to what it can negotiate with the remote modem on the
PSTN/ISDN. The parameters User Rate and FNUR (Fixed Network User Rate), if present, has no
meaning when Modem Type is autobauding type 1.
multi self selecting speed modem: This term applies to V series modems capable of handling one or
more lower speeds as a fall back position. When such a modem is requested in the call setup or call
confirm message from the MS in association with a non transparent service, the MSC/IWF may select any
of the speeds supported according to the negotiation with the remote modem on the PSTN/ISDN. The
parameters User Rate and FNUR (Fixed Network User Rate), if present, has no meaning when Modem
Type is autobauding type 1.
unrestricted 64 kbit/s network: A digital network which has 64 kbit/s octet-structured Information
Transfer Capability (ITC) with no restrictions on the contents of each octet.
restricted 64 kbit/s network: CCITT I.464 defines '"restricted 64 kbit/s transfer capability" as "64 kbit/s
octet-structured capability with the exception that an all-zero octet is not permitted". In this specification,
the term "restricted 64 kbit/s network" refers not only to networks with the I.464 restriction but also to those
in whic
...