SIST ETS 300 604 E7:2003

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 4.13.1)

SUBJECT V.24 signalling

Digitalni celični telekomunikacijski sistem (faza 2) – Splošne zahteve za medsebojno delovanje med javnim kopenskim mobilnim omrežjem (PLMN) in digitalnim omrežjem z integriranimi storitvami (ISDN) ali javnim komutiranim telefonskim omrežjem (PSTN) (GSM 09.07, različica 4.13.1)

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 300 604 ed.7 (1999-03) - 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 4.13.1)

Standards Content (Sample)

SLOVENSKI STANDARD
SIST ETS 300 604 E7:2003
01-december-2003
'LJLWDOQLFHOLþQLWHOHNRPXQLNDFLMVNLVLVWHPID]D±6SORãQH]DKWHYH]D
PHGVHERMQRGHORYDQMHPHGMDYQLPNRSHQVNLPPRELOQLPRPUHåMHP3/01LQ
GLJLWDOQLPRPUHåMHP]LQWHJULUDQLPLVWRULWYDPL,6'1DOLMDYQLPNRPXWLUDQLP
WHOHIRQVNLPRPUHåMHP3671*60UD]OLþLFD
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 4.13.1)
Ta slovenski standard je istoveten z: ETS 300 604 Edition 7
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 300 604 E7:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST ETS 300 604 E7:2003

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SIST ETS 300 604 E7:2003
EUROPEAN ETS 300 604
TELECOMMUNICATION March 1999
STANDARD Seventh Edition
Source: SMG Reference: RE/SMG-040907PR6
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 4.13.1)
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 1999. 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 .12
4 Introduction.13
5 Not used.14
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 .18
7.4 Numbering .18
7.5 Supplementary service interworking.18
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 .19
9.2.1 Network interworking mobile originated .19
9.2.1.1 Selection of interworking function.19
9.2.1.2 Modem Selection.19
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 .25
9.2.3.1 Not used .25
9.2.3.2 Rate adaptation process in MSC/IWF .25
9.2.3.3 Mapping of signalling MS/MSC/IWF to modem interface
requirements.25
9.2.3.4 Establishment of end-to-end terminal synchronizations .26
9.2.3.5 Network Independent Clocking (NIC).27
9.2.4 Non-transparent service support.27
9.2.4.1 MSC-IWF Rate adaptation scheme.27
9.2.4.2 Protocol layer structure in the MSC/IWF .27
9.2.4.3 Re-constitution of user data.27
9.2.4.4 Layer 2 relay functionality .28
9.2.4.5 In band signalling mapping flow control.28
9.2.4.5.1 Conditions requiring flow control
towards the fixed network .28

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9.2.4.5.2 Conditions requiring flow control
towards the MS . 29
9.2.4.6 Data buffers . 29
9.2.4.6.1 Transmit buffers (towards MS). 29
9.2.4.6.2 Receive buffers (from MS) . 29
9.2.4.7 Transportation of the Break condition. 29
9.2.4.8 In band signalling mapping modem status information. 29
9.2.4.9 Support of out-band flow control . 30
9.2.4.10 Establishment of end-to-end terminal synchronizations . 30
9.3 Interworking Alternate Speech / Data Calls. 31
9.3.1 Alternate Speech/Data Interworking. 31
9.3.1.1 General . 31
9.3.1.2 Mobile originated PSTN terminated calls. 31
9.3.1.3 PSTN originated mobile terminated calls. 31
9.3.2 Speech followed by data interworking . 32
9.3.2.1 General . 32
10 Interworking to the ISDN. 32
10.1 Speech Calls . 32
10.2 Data Calls. 32
10.2.1 Network interworking mobile originated. 33
10.2.1.1 Circuit switched calls. 33
10.2.1.2 Packet calls. 33
10.2.2 Network interworking mobile terminated . 33
10.2.2.1 Circuit switched calls. 48
10.2.2.2 Packet calls. 48
10.2.3 Transparent service support (see GSM 03.10) . 48
10.2.3.1 MSC - IWF rate adaptation scheme . 48
10.2.3.2 Rate adaptation process in MSC/IWF . 48
10.2.3.3 Mapping of signalling MS/MSC/IWF to modem interface
requirements . 48
10.2.3.4 Establishment of end-to-end terminal synchronizations . 49
10.2.3.5 Network independent Clocking (NIC). 50
10.2.4 Non-transparent service support (see GSM 03.10). 50
10.2.4.1 MSC - IWF Rate adaptation scheme. 50
10.2.4.2 Protocol layer structure in the MSC/IWF. 50
10.2.4.3 Re-constitution of user data . 50
10.2.4.4 Layer 2 relay functionality. 50
10.2.4.5 In band signalling mapping flow control . 51
10.2.4.5.1 Conditions requiring flow control - if
flow control is provided - towards the
fixed network . 51
10.2.4.5.2 Conditions requiring flow control
towards the MS . 51
10.2.4.6 Data buffers . 52
10.2.4.6.1 Transmit buffers (towards MS). 52
10.2.4.6.2 Receive buffers (from MS) . 52
10.2.4.7 BREAK Indication. 52
10.2.4.8 Signalling mapping modem status information or in band
rate adapted frame information. 52
10.2.4.9 Support of out-band flow control . 52
10.2.4.10 Synchronizations. 52
10.2.4.10.1 V110 Frame synchronizations. 52
10.2.4.10.2 RLP Frame start indication. 52
10.2.4.10.3 L2R Frame synchronizations. 53
10.2.4.10.4 Establishment of end-to-end terminal
synchronizations. 53
10.2.5 DTE/Modem interface (Filtering) . 53
10.3 Interworking Alternate speech data calls . 54
10.3.1 Alternate speech data bearer interworking. 55
10.3.1.1 General . 55
10.3.1.2 Mobile originated ISDN terminated . 55
10.3.1.3 ISDN originated mobile terminated . 55

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10.3.2 Speech followed by data interworking.56
10.3.2.1 General.56
11 V.110 Frame Synchronization .56
11.1 Initial V.110 frame synchronization .56
11.2 Action on loss of V.110 frame synchronization for non transparent services .56
11.3 Action on loss of V.110 frame synchronization for transparent services .56
Annex A (informative): SDLs.58
Annex B (informative): Change Request History .60
History.61

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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 SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially
Essential, IPRs notified to ETSI in respect of ETSI standards", which is available free of charge 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 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 (MSC) Interworking Functions (IWFs) and
requirements to support interworking between:
a) Public Land Mobile Network (PLMN) and Public Switched Telephone Network (PSTN);
b) PLMN and Integrated Services Digital Network (ISDN).
The contents of this ETS is subject to continuing work within SMG and may change following formal SMG
approval. Should SMG modify the contents of this ETS, it will be resubmitted for OAP by ETSI with an
identifying change of release date and an increase in version number as follows:
Version 4.x.y
where:
4 indicates GSM Phase 2;
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 of this ETS: 26 March 1999
Date of latest announcement of this ETS (doa): 30 June 1999
Date of latest publication of new National Standard
or endorsement of this ETS (dop/e): 31 December 1999
Date of withdrawal of any conflicting National Standard (dow): 31 December 1999

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1 Scope
The purpose of this European Telecommunication Standard (ETS) is to identify the Mobile-services
Switching Centre (MSC)/Interworking Functions (IWFs) and requirements to support interworking
between:
i) PLMN and PSTN;
ii) 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.110: "Support of data terminal equipments (DTEs)
with V-series interfaces by an integrated services digital network".
[5] ETS 300 102-1 Edition 1: "Integrated Services Digital Network (ISDN);
User-network interface layer 3 Specifications for basic call control".
[6] 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)".
[7] GSM 01.04 (ETR 100): "Digital cellular telecommunications system (Phase 2);
Abbreviations and acronyms".
[8] GSM 02.01 (ETS 300 500): "Digital cellular telecommunications system
(Phase 2); Principles of telecommunications services supported by a GSM
Public Land Mobile Network (PLMN)".
[9] GSM 02.02 (ETS 300 501): "Digital cellular telecommunications system
(Phase 2); Bearer Services (BS) supported by a GSM Public Land Mobile
Network (PLMN)".
[10] GSM 02.03 (ETS 300 502): "Digital cellular telecommunications system
(Phase 2); Teleservices supported by a GSM Public Land Mobile Network
(PLMN)".
[11] GSM 02.04 (ETS 300 503): "Digital cellular telecommunications system
(Phase 2); General on supplementary services".

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[12] GSM 02.81 (ETS 300 514): "Digital cellular telecommunications system
(Phase 2); Line identification supplementary services - Stage 1".
[13] GSM 02.82 (ETS 300 515): "Digital cellular telecommunications system
(Phase 2); Call Forwarding (CF) supplementary services - Stage 1".
[14] GSM 02.83 (ETS 300 516): "Digital cellular telecommunications system
(Phase 2); Call Waiting (CW) and Call Hold (HOLD) supplementary services -
Stage 1".
[15] GSM 02.84 (ETS 300 517): "Digital cellular telecommunications system
(Phase 2); MultiParty (MPTY) supplementary services - Stage 1".
[16] GSM 02.85 (ETS 300 518): "Digital cellular telecommunications system
(Phase 2); Closed User Group (CUG) supplementary services - Stage 1".
[17] GSM 02.86 (ETS 300 519): "Digital cellular telecommunications system
(Phase 2); Advice of charge (AoC) supplementary services - Stage 1".
[18] GSM 02.88 (ETS 300 520): "Digital cellular telecommunications system
(Phase 2); Call Barring (CB) supplementary services - Stage 1".
[19] GSM 03.03 (ETS 300 523): "Digital cellular telecommunications system
(Phase 2); Numbering, addressing and identification".
[20] GSM 03.08 (ETS 300 526): "Digital cellular telecommunications system
(Phase 2); Organization of subscriber data".
[21] GSM 03.11 (ETS 300 529): "Digital cellular telecommunications system
(Phase 2); Technical realization of supplementary services".
[22] GSM 03.45 (ETS 300 538): "Digital cellular telecommunications system
(Phase 2); Technical realization of facsimile group 3 transparent".
[23] GSM 03.46 (ETS 300 539): "Digital cellular telecommunications system
(Phase 2); Technical realization of facsimile group 3 non-transparent".
[24] GSM 03.50 (ETS 300 540): "Digital cellular telecommunications system
(Phase 2); Transmission planning aspects of the speech service in the GSM
Public Land Mobile Network (PLMN) system".
[25] GSM 04.08 (ETS 300 557): "Digital cellular telecommunications system
(Phase 2); Mobile radio interface layer 3 specification".
[26] GSM 04.21 (ETS 300 562): "Digital cellular telecommunications system
(Phase 2); Rate adaption on the Mobile Station - Base Station System (MS -
BSS) Interface".
[27] GSM 04.22 (ETS 300 563): "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".
[28] GSM 07.01 (ETS 300 582): "Digital cellular telecommunications system
(Phase 2); General on Terminal Adaptation Functions (TAF) for Mobile Stations
(MS)".
[29] GSM 07.02 (ETS 300 583): "Digital cellular telecommunications system
(Phase 2); Terminal Adaptation Functions (TAF) for services using
asynchronous bearer capabilities".

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[30] GSM 07.03 (ETS 300 584): "Digital cellular telecommunications system
(Phase 2); Terminal Adaptation Functions (TAF) for services using synchronous
bearer capabilities".
[31] GSM 07.05 (ETS 300 585): "Digital cellular telecommunications 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)".
[32] GSM 08.20 (ETS 300 591): "Digital cellular telecommunications system
(Phase 2); Rate adaption on the Base Station System - Mobile-services
Switching Centre (BSS - MSC) interface".
[33] GSM 08.60 (ETS 300 597): "Digital cellular telecommunications system
(Phase 2); Inband control of remote transcoders and rate adaptors for full rate
traffic channels".
[34] GSM 09.02 (ETS 300 599): "Digital cellular telecommunications system
(Phase 2); Mobile Application Part (MAP) specification".
[35] GSM 09.03 (ETS 300 600): "Digital cellular telecommunications 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)".
[36] GSM 09.05 (ETS 300 602): "Digital cellular telecommunications 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".
[37] GSM 09.06 (ETS 300 603): "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".
NOTE: As regards ETS 300 102-1 [5], the edition 1 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.

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3 Definitions and abbreviations
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.
For the purposes of this ETS, the following definitions apply:
bearer capability information: Specific information defining the lower layer characteristics required
within the network.
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 inter-network signalling system.
autobauding type 1: This information element value may be contained in the setup or call confirm
messages from the mobile station 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 maximum speed to be used by the MSC/IWF is the user speed indicated
in the setup/call confirm message.
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. In this
instance the maximum starting negotiation speed to be used by the MSC/IWF is the one indicated by the
user speed in the setup/call confirm message.
In addition to those below abbreviations used in this ETS are listed in GSM 01.04.
ADPCM Adaptive Differential Pulse Coded Modulation
DP Dial Pulse
ITC Information Transfer Capability
LE Local Exchange
NT Network Termination
PABX Private Automatic Branch Exchange
SPC Stored Program Control
SS No.7 Signalling System No.7
TE Terminal Equipment
TA Terminal Adaptor
TUP Telephone User Part (of Signalling System No.7)
DSS1 Digital Subscriber Signalling 1
UNI User Network Interface

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4 Introduction
General Network Interworking Scenarios are described in GSM 09.01. Since the numbering plan for the
ISDN era (E.164) includes the numbering plan for the telephone network (E.163), it is not possible to
distinguish by the number whether a given subscriber is a PSTN or ISDN subscriber. Further, in some
countries both PSTN and ISDN subscribers will be connected to the same exchange, so the only
difference for this type of combined network will be in the nature of the customer access. In this document
a PSTN is considered to support only an analogue interface towards the subscriber. An ISDN shall be
considered to support digital interface towards the subscriber. In addition, the ISDN is considered to
support a standardized outband signalling protocol both between the subscriber and the network and
within the network, i.e. DSS1 and ISUP, thus enabling the generation and transport of Compatibility
Information for compatibility checking and terminal/function/service selection at the user-network interface
as well as for MSC/IWF selection.
There now exist networks which do not fall into either of these categories in that they provide for digital
connectivity from subscriber to subscriber through the network. The subscribers have access to a wide
range of services by a limited set of standard multi-purpose user network interfaces. However, these
networks do not support the standardized inter-exchange signalling protocol throughout, in that they are
e.g. using TUP or National User Part (NUP). These types of network support 64 kbit/s
...