ETSI TS 103 389 V3.1.1 (2017-05)

Railway Telecommunications (RT); Global System for Mobile communications (GSM); Usage of Session Initiation Protocol (SIP) on the Network Switching Subsystem (NSS) to Fixed Terminal Subsystem (FTS) interface for GSM Operation on Railways

RTS/RT-0044

General Information

• Status: Published
• Publication Date: 04-May-2017
• Technical Committee: RT - Railway telecommunications
• Current Stage: 12 - Completion
• Due Date: 22-May-2017
• Completion Date: 05-May-2017

Standards Content (Sample)

ETSI TS 103 389 V3.1.1 (2017-05)






TECHNICAL SPECIFICATION
Railway Telecommunications (RT);
Global System for Mobile communications (GSM);
Usage of Session Initiation Protocol (SIP)
on the Network Switching Subsystem (NSS)
to Fixed Terminal Subsystem (FTS)
interface for GSM Operation on Railways

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2 ETSI TS 103 389 V3.1.1 (2017-05)



Reference
RTS/RT-0044
Keywords
GSM-R, railways
ETSI
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ETSI

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3 ETSI TS 103 389 V3.1.1 (2017-05)
Contents
Intellectual Property Rights . 5
Foreword . 5
Modal verbs terminology . 5
Introduction . 5
1 Scope . 7
2 References . 7
2.1 Normative references . 7
2.2 Informative references . 9
3 Definitions and abbreviations . 10
3.1 Definitions . 10
3.2 Abbreviations . 12
4 Reference System Architecture . 13
5 Interface Functionality . 14
5.0 General Description . 14
5.1 Basic Call . 15
5.1.0 Primary Function . 15
5.1.1 Progress Indication . 15
5.1.2 Early Media . 15
5.2 Connected Parties Identity Information . 15
5.3 Call Hold . 15
5.4 Multi Level Precedence and Pre-emption . 15
5.5 Voice Group Call and Broadcast Call Control . 15
5.6 User-User-Information-Element Transport . 16
5.7 Reason Transport . 16
5.8 Call Transfer Notification . 16
5.9 Conferencing . 16
5.10 Call Forwarding . 16
5.11 Call Waiting . 17
6 Signalling Interface . 17
6.1 Network Layer Protocol . 17
6.2 Transport Layer Protocol . 17
6.3 Signalling Protocol . 17
6.3.0 General Provisions . 17
6.3.1 SIP Entities . 18
6.3.1.0 SIP networks . 18
6.3.1.1 SIP User Agent . 18
6.3.1.2 SIP Proxy . 18
6.3.2 SIP Request Methods . 18
6.3.3 SIP Responses . 19
6.3.4 SIP Header Fields . 19
6.3.5 SIP Bodies . 21
6.3.6 SIP URI Convention . 22
6.3.6.0 General provisions . 22
6.3.6.1 Display Name . 23
6.3.6.2 User Part . 23
6.3.6.3 Host Part . 23
6.3.6.4 URI Parameters . 24
6.3.6.5 Use . 24
6.3.6.6 Examples . 25
6.3.7 Option Tags . 26
6.3.8 Feature Parameter . 26
6.4 Interface Functionality to Signalling Interface Mapping . 26
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4 ETSI TS 103 389 V3.1.1 (2017-05)
6.4.0 General . 26
6.4.1 Basic Call . 26
6.4.2 Connected Parties Identity Information . 28
6.4.3 Media Session Renegotiation and Call Hold . 30
6.4.4 Early Media . 32
6.4.5 Multi Level Precedence and Pre-emption . 34
6.4.5.0 General Provisions . 34
6.4.5.1 Resource Priority . 35
6.4.5.2 Reason Indication for Precedence and Pre-emption Events . 35
6.4.5.3 Signalling Procedure for Precedence Call Blocking . 35
6.4.5.4 Signalling Procedure for Pre-emption . 36
6.4.6 Group Call and Broadcast Call Control . 37
6.4.7 User-to-User-Information-Element Transport . 37
6.4.8 Release Cause Transport . 37
6.4.9 SIP Session Timer . 38
6.4.10 OPTIONS Processing . 39
6.4.10.0 General Provisions . 39
6.4.10.1 OPTIONS Heartbeating . 40
6.4.11 Signalling for Group Call and Broadcast Call Control . 40
6.4.12 Call Transfer Notification . 42
6.4.13 Conferencing. 45
6.4.14 Call Forwarding . 48
6.4.15 Call Waiting . 50
7 Media Interface . 51
7.1 Network Layer Protocol . 51
7.2 Transport Layer Protocol . 51
7.3 Real-Time Transport Protocol . 51
7.3.0 General Provisions . 51
7.3.1 Media inactivity detection . 52
7.4 Media Codecs . 52
7.4.0 General Provisions . 52
7.4.1 DTMF . 52
8 Recorder Interface . 53
8.1 Reference Architecture . 53
8.2 Interface Functionality . 54
8.2.0 General . 54
8.2.1 Recording Session . 54
8.3 Signalling Interface . 54
8.4 Media interface . 57
8.4.0 General . 57
8.4.1 Media mixing . 57
8.4.2 Multiple streams . 57
Annex A (normative): Locating SIP Entities . 58
Annex B (informative): Quality of Service framework . 61
Annex C (informative): Security Framework . 62
Annex D (informative): Mapping of EIRENE to Interface Features . 63
Annex E (informative): Group Call Control Scenarios . 65
Annex F (informative): Bibliography . 67
History . 68

ETSI

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5 ETSI TS 103 389 V3.1.1 (2017-05)
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 (https://ipr.etsi.org/).
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 Technical Specification (TS) has been produced by ETSI Technical Committee Railway Telecommunications
(RT).
Modal verbs terminology
In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and
"cannot" are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of
provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
Introduction
While a number of interoperability specifications for various interfaces at various layers of GSM-R systems exist, the
interface between the Network Switching Subsystem (NSS) and the Fixed Terminal Subsystem (FTS) has not yet been
addressed by any interoperability specification activity.
In most of the GSM-R system deployments available at the time of the creation of the present document, the Network
Switching Subsystem and the Fixed Terminal Subsystem are interconnected using TDM based interfaces such as
DSS1 [i.2].
ETSI TS 102 610 [9] specifies the usage and format of UUIE for call-related end-to-end functionality in GSM-R
systems but no other interworking topics.
The present document addresses the interoperability specification gap between the Network Switching Subsystem and
the Fixed Terminal Subsystem with an interface based on the Internet Protocol (IP) [2], the Session Initiation Protocol
(SIP) [3], the Session Description Protocol (SDP) [6] and the Real-Time Transport Protocol (RTP) [7].
In addition to the table of contents, the following explanation will help you navigate through and understand the
contents of the present document:
• Clauses 1 to 3 are predefined by ETSI.
• Clause 4 shows and explains the reference system architecture and identifies the interface(s) for the present
document.
• Clause 5 holds the functional requirements for the interface subject to the present document.
• Clause 6 specifies in detail the signalling interface for all supported functions and services.
• Clause 7 specifies in detail the media interface.
• Clause 8 specifies the additions and changes for a voice recorder interface.
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6 ETSI TS 103 389 V3.1.1 (2017-05)
• Annex A explains the mechanism to locate SIP entities at the present interface.
• Annex B contains recommendations on the use and implementation of standardized Quality of Service
mechanisms at the present interface.
• Annex C contains recommendations about the security mechanisms.
• Annex D contains a mapping table of EIRENE [1] to interface features.
• Annex E contains a description of group call control scenarios.
ETSI

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7 ETSI TS 103 389 V3.1.1 (2017-05)
1 Scope
The present document defines the signalling and media interface between the Network Switching Subsystem and the
Fixed Terminal Subsystem in order to provide a clear set of services needed for GSM-R operations. This includes voice
call service and available call-related supplementary services. In addition, requirements for specific implementation of
the signalling and media interface within either the Network Switching Subsystem or the Fixed Terminal Subsystem are
stated where applicable. The present document addresses the Internet Layer and upwards of the Internet Protocol Suite
IETF RFC 1122 [i.18] on the signalling and media interface.
Any service other than voice call service and call-related supplementary services (such as data services, Short Message
Service, etc.) is out of scope of the present document; additional features may be addressed in future releases.
The present document does not specify any other interface between the Network Switching Subsystem and the Fixed
Terminal Subsystem nor does it cover any internal interfaces of either NSS or FTS. Such interfaces may be addressed in
a future release of the present document.
The present document does not address any specific 3GPP Release or Architecture.
2 References
2.1 Normative references
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
referenced document (including any amendments) applies.
Referenced documents which are not found to be publicly available in the expected location might be found at
http://docbox.etsi.org/Reference.
NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee
their long term validity.
The following referenced documents are necessary for the application of the present document.
[1] UIC P001D010 (Version 15.1): "UIC Project EIRENE System Requirements Specification".
NOTE: Available at http://www.uic.org/IMG/pdf/eirene_srs_15.1.pdf.
[2] IETF RFC 791 (1981): "Internet Protocol".
[3] IETF RFC 3261 (2002): "SIP: Session Initiation Protocol".
[4] IETF RFC 3264 (2002): "An Offer/Answer Model Session Description Protocol (SDP)".
[5] IETF RFC 4733 (2006): "RTP Payload for DTMF Digits, Telephony Tones, and Telephony
Signals".
[6] IETF RFC 4566 (2006): "SDP: Session Description Protocol".
[7] IETF RFC 3550 (2003): "RTP: A Transport Protocol for Real-Time Applications".
[8] IETF RFC 3326 (2002): "The Reason Header Field for the Session Initiation Protocol (SIP)".
[9] ETSI TS 102 610 (V1.1.0): "Railways Telecommunications (RT); Global System for Mobile
communications (GSM); Usage of the User to User Information Element for GSM Operation on
Railways".
[10] IETF RFC 5234 (2008): "Augmented BNF for Syntax Specifications: ABNF".
[11] IETF RFC 3262 (2002): "Reliability of Provisional Responses in Session Initiation Protocol
(SIP)".
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8 ETSI TS 103 389 V3.1.1 (2017-05)
[12] IETF RFC 4412 (2006): "Communications Resource Priority for the Session Initiation Protocol
(SIP)".
[13] IETF RFC 3325 (2002): "Private Extensions to the Session Initiation Protocol (SIP) for Asserted
Identity within Trusted Networks".
[14] IETF RFC 5876 (2010): "Updates to Asserted Identity in the Session Initiation Protocol (SIP)".
[15] IETF RFC 3323 (2002): "A Privacy Mechanism for the Session Initiation Protocol (SIP)".
[16] IETF RFC 4028 (2005): "Session Timers in the Session Initiation Protocol (SIP)".
[17] IETF RFC 3311 (2002): "The Session Initiation Protocol (SIP) UPDATE Method".
[18] Void.
[19] Void.
[20] Void.
[21] Void.
[22] Recommendation ITU-T Q.850 (1998): "Usage of cause and location in the Digital Subscriber
Signalling System No. 1 and the Signalling System No. 7 ISDN user part".
[23] Recommendation ITU-T E.164 (2010): "The international public telecommunication numbering
plan".
[24] Recommendation ITU-T Q.955.3 (1993): "Stage 3 description for community of interest
supplementary services using DSS 1: Multi-level precedence and pre-emption (MLPP)".
[25] IETF RFC 3986 (2005): "Uniform Resource Identifier (URI): Generic Syntax".
[26] IETF RFC 768 (1980): "User Datagram Protocol".
[27] Recommendation ITU-T G.711 (1988): "Pulse code modulation (PCM) of voice frequencies".
[28] IETF RFC 2833 (2000): "RTP Payload for DTMF Digits, Telephony Tones and Telephony
Signals".
[29] Void.
[30] IETF RFC 3840 (2004): "Indicating User Agent Capabilities in the Session Initiation Protocol
(SIP)".
[31] IETF RFC 4574 (2006): "The Session Description Protocol (SDP) Label Attribute".
[32] Recommendation ITU-T I.255.3 (1990): "Multi-Level Precedence and Pre-emption service".
[33] IETF RFC 4579 (2006): "Session Initiation Protocol (SIP) Call Control - Conferencing for User
Agents".
[34] IETF RFC 3891 (2004): "The Session Initiation Protocol (SIP) "Replaces" Header".
[35] IETF RFC 7462 (2015): "URNs for the Alert-Info Header Field of the Session Initiation Protocol
(SIP)".
[36] IETF RFC 4244 (2005): "An Extension to the Session Initiation Protocol (SIP) for Request History
Information".
[37] IETF RFC 4458 (2006): "Session Initiation Protocol (SIP) URIs for Applications such as
Voicemail and Interactive Voice Response (IVR)".
[38] ETSI TS 129 163 (V12.13.0): "Digital cellular telecommunications system (Phase 2+) (GSM);
Universal Mobile Telecommunications System (UMTS); LTE; Interworking between the IP
Multimedia (IM) Core Network (CN) subsystem and Circuit Switched (CS) networks (3GPP TS
29.163 version 12.13.0 Release 12)".
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9 ETSI TS 103 389 V3.1.1 (2017-05)
2.2 Informative references
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
referenced document (including any amendments) applies.
NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee
their long term validity.
The following referenced documents are not necessary for the application of the present document but they assist the
user with regard to a particular subject area.
[i.1] IETF RFC 7433 (2015): "A Mechanism for Transporting User to User Call Control Information in
SIP".
[i.2] ETSI ETS 300 403-1 (V1.3.2): "Integrated Services Digital Network (ISDN); Digital Subscriber
Signalling System No. one (DSS1) protocol; Signalling network layer for circuit-mode basic call
control; Part 1: Protocol specification [ITU-T Recommendation Q.931 (1993), modified]".
[i.3] IETF RFC 6086 (2011): "Session Initiation Protocol (SIP) INFO Method and Package
Framework".
[i.4] IETF RFC 3428 (2002): "Session Initiation Protocol (SIP) Extension for Instant Messaging".
[i.5] IETF RFC 3515 (2001): "The Session Initiation Protocol (SIP) Refer Method".
[i.6] IETF RFC 3265 (2002): "Session Initiation Protocol (SIP)-Specific Event Notification".
[i.7] IETF RFC 3903 (2004): "Sess
...