ETSI ETS 300 392-10-23 ed.2 (1999-09)

Terrestrial Trunked Radio (TETRA); Voice plus Data (V+D); Part 10: Supplementary services stage 1; Sub-part 23: Call completion on no reply

RE/TETRA-03001-10-23

Prizemni snopovni radio (TETRA) – Govor in podatki (V+D) – 10. del: Dopolnilne storitve stopnje 1 – 23. poglavje: Dokončanje klicanja, ko ni odziva

General Information

• Status: Published
• Publication Date: 13-Sep-1999
• Technical Committee: TCCE 3 - TCCE Air Interface and Network Protocols
• Current Stage: 12 - Completion
• Due Date: 10-Sep-1999
• Completion Date: 14-Sep-1999
• Mandate: T-172-1A
• Ref Project: SIST ETS 300 392-10-23 E2:2003 - Terrestrial Trunked Radio (TETRA); Voice plus Data (V+D); Part 10: Supplementary services stage 1; Sub-part 23: Call completion on no reply

Standards Content (Sample)

SLOVENSKI STANDARD
SIST ETS 300 392-10-23 E2:2003
01-december-2003
3UL]HPQLVQRSRYQLUDGLR7(75$±*RYRULQSRGDWNL9'±GHO'RSROQLOQH
VWRULWYHVWRSQMH±SRJODYMH'RNRQþDQMHNOLFDQMDNRQLRG]LYD
Terrestrial Trunked Radio (TETRA); Voice plus Data (V+D); Part 10: Supplementary
services stage 1; Sub-part 23: Call completion on no reply
Ta slovenski standard je istoveten z: ETS 300 392-10-23 Edition 2
ICS:
33.070.10 Prizemni snopovni radio Terrestrial Trunked Radio
(TETRA) (TETRA)
SIST ETS 300 392-10-23 E2:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST ETS 300 392-10-23 E2:2003

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SIST ETS 300 392-10-23 E2:2003
EUROPEAN ETS 300 392-10-23
TELECOMMUNICATION September 1999
STANDARD Second Edition
Source: TETRA Reference: RE/TETRA-03001-10-23
ICS: 33.020
Key words: CCNR, data, radio, speech, stage 1, supplementary service, TETRA
Terrestrial Trunked Radio (TETRA);
Voice plus Data (V+D);
Part 10: Supplementary services stage 1;
Sub-part 23: Call completion on no reply
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
Foreword . 5
1 Scope. 7
2 References. 7
3 Definitions, symbols and abbreviations. 8
3.1 Definitions. 8
3.2 Symbols. 9
3.3 Abbreviations. 10
3.3.1 General abbreviations. 10
3.3.2 Supplementary service abbreviations . 10
4 SS-CCNR Stage 1 Specification. 11
4.1 Description. 11
4.1.1 General description. 11
4.1.2 Qualifications on applicability to telecommunication services. 11
4.2 Procedures . 11
4.2.1 Provision/Withdrawal . 11
4.2.2 Normal Procedures. 11
4.2.2.1 Activation/deactivation/registration/interrogation. 11
4.2.2.2 Invocation and operation. 12
4.2.2.3 Cancellation. 13
4.2.2.4 Timers . 13
4.2.3 Exceptional procedures . 13
4.2.3.1 Activation/deactivation/registration and Interrogation. 13
4.2.3.2 Invocation and operation. 13
4.2.3.2.1 Rejection of SS-CCNR service
request. 13
4.2.3.2.2 User A is busy on SS-CCNR recall . 14
4.2.3.2.3 Network congestion. 14
4.2.3.2.4 User B becomes busy after successful
SS-CCNR recall. 14
4.2.3.2.5 Duplicate SS-CCNR requests . 14
4.2.3.2.6 Other situations . 15
4.2.3.2.7 Other failure situations . 15
4.2.3.3 Cancellation. 15
4.3 Interactions with other supplementary services. 15
4.3.1 Calling Line Identification Presentation (SS-CLIP) . 15
4.3.2 Connected Line Identification Presentation (SS-COLP) . 15
4.3.3 Calling/Connected Line Identification Restriction (SS-CLIR). 15
4.3.4 Completion of Calls on Busy Subscriber (SS-CCBS) . 16
4.3.5 Call Forwarding Unconditional (SS-CFU) . 16
4.3.5.1 SS-CFU activated by user B before user A requests SS-
CCNR. 16
4.3.5.2 SS-CFU activated by user B after user A requests SS-
CCNR. 16
4.3.5.3 SS-CFU activation by user A. 16
4.3.6 Call Forwarding Busy (SS-CFB) . 16
4.3.6.1 SS-CFB activated by user B before user A requests SS-
CCNR. 16
4.3.6.2 SS-CFB activated by user B after user A requests SS-
CCNR. 16
4.3.6.3 SS-CFB activation by user A. 16
4.3.7 Call Forwarding on No Reply (SS-CFNR). 17

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4.3.8 Call Report (SS-CR).17
4.3.9 Talking Party Identification (SS-TPI) .17
4.3.10 Call Forwarding on Not Reachable (SS-CFNRc) .17
4.3.11 List Search Call (SS-LSC).17
4.3.12 Call Authorized by Dispatcher (SS-CAD) .17
4.3.13 Short Number Addressing (SS-SNA) .17
4.3.14 Area Selection (SS-AS).17
4.3.15 Access Priority (SS-AP) .18
4.3.16 Priority Call (SS-PC).18
4.3.17 Call Waiting (SS-CW) .18
4.3.18 Call Hold (SS-HOLD) .18
4.3.19 Late Entry (SS-LE) .18
4.3.20 Transfer of Control (SS-TC).18
4.3.21 Pre-emptive Priority Call (SS-PPC).18
4.3.22 Include Call (SS-IC).18
4.3.23 Advice of Charge (SS-AoC) .18
4.3.24 Barring of Outgoing Calls (SS-BOC).18
4.3.25 Barring of Incoming Calls (SS-BIC).18
4.2.26 Discreet Listening (SS-DL).18
4.2.27 Ambiance Listening (SS-AL) .19
4.2.28 Dynamic Group Number Assignment (SS-DGNA).19
4.2.29 Call Retention (SS-CRT).19
4.2.30 Interaction with ANFs .19
4.2.30.1 Mobility.19
4.2.30.1.1 Migration of user B while SS-CCNR is
active for a given call .19
4.2.30.1.2 Migration of user A while SS-CCNR is
active.19
4.2.30.1.3 Migration of either user A or user B to
a SwMI not supporting SS-CCNR.19
4.2.31 Inter-working considerations .19
4.3 SS-CCNR Overall SDL .20
Annex A (informative): Bibliography.22
History.23

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Foreword
This European Telecommunication Standard (ETS) has been produced by the Terrestrial Trunked Radio
(TETRA) Project of the European Telecommunications Standards Institute (ETSI).
This ETS is a multi-part standard and will consist of the following parts:
Part 1: "General network design";
Part 2: "Air Interface (AI)";
Part 3: "Interworking at the Inter-System Interface (ISI)";
Part 4: "Gateways basic operation";
Part 5: "Peripheral Equipment Interface (PEI)";
Part 6: "Line connected Station (LS)";
Part 7: "Security";
Part 9: "General requirements for supplementary services";
Part 10: "Supplementary services stage 1";
Part 11: "Supplementary services stage 2";
Part 12: "Supplementary services stage 3";
Part 13: "SDL model of the Air Interface (AI)";
Part 14: "Protocol Implementation Conformance Statement (PICS) proforma specification".
Transposition dates
Date of adoption of this ETS: 3 September 1999
Date of latest announcement of this ETS (doa): 31 December 1999
Date of latest publication of new National Standard
or endorsement of this ETS (dop/e): 30 June 2000
Date of withdrawal of any conflicting National Standard (dow): 30 June 2000

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1 Scope
This ETS specifies the Call Completion on No Reply (SS-CCNR) supplementary service which is
applicable to various basic services supported by TETRA Switching and Management Infrastructures
(SwMIs). TETRA basic services are specified in ETS 300 392-2 [8].
SS-CCNR allows completion of a call to a subscriber that was unsuccessful because of a no reply
condition. SS-CCNR enables a calling user A, encountering a destination user B, that, though alerted,
does not answer, to have the call completed when user B is available, without having to make a new
call attempt.
Supplementary service specifications are produced in three stages, according to the method described in
ITU-T Recommendation I.210 [4]. This ETS contains the stage 1 specifications of SS-CCNR.
The stage 1 descriptions specify the supplementary services as seen by users of networks.
This ETS is applicable to circuit mode TETRA tele-services and bearer services only. This ETS does not
describe the case where the MS is not reachable.
Man Machine Interfaces and charging principles are outside the scope of this ETS.
The first edition of this ETS was presented as a delta document to the first edition of ECMA-185 [2]. This
version has been redrafted based on the latest published text of ECMA-185 [2] as a self contained
document so as to be more readable. Additions to ECMA-185 [2] have been made to take into account
particular TETRA specifics and to include user requirements and situations not addressed in
ECMA-185 [2].
NOTE: Contrary to PISN SS-CCBS and SS-CCNR which are both specified in ECMA-185 [2],
TETRA SS-CCBS and TETRA SS-CCNR are specified in two separate ETSs.
2 References
This ETS incorporates by dated and undated reference, provisions from other publications. These
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] Void.
[2] Standard ECMA-185 (1997): "Private Integrated Services Network (PISN);
Specification, Functional Model and Information Flows; Call Completion
Supplementary Services (CCSD)".
[3] ITU-T Recommendation I.112 (1993): "Vocabulary of terms for ISDNs".
[4] ITU-T Recommendation I.210 (1993): "Principles of telecommunication services
supported by an ISDN and the means to describe them".
[5] ITU-T Recommendation I.221 (1993): "Common specific characteristics of
services".
[6] ITU-T Recommendation Z.100 (1993): "CCITT specification and description
language (SDL)".
[7] Void.
[8] ETS 300 392-2 (1995): "Terrestrial Trunked Radio (TETRA); Voice plus Data
(V+D); Part 2: Air Interface (AI)".

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[9] ETS 300 392-9 (1997): "Terrestrial Trunked Radio (TETRA); Voice plus Data
(V+D); Part 9: General requirements for supplementary services".
[10] CCITT Recommendation Q.9 (1988): "Vocabulary of switching and signalling
terms".
3 Definitions, symbols and abbreviations
3.1 Definitions
For the purposes of this ETS, the following definitions apply:
activity: Answering an incoming call or originating an outgoing call. Applies in particular to user B.
Additional Network Feature (ANF): Capability, over and above that of a basic service, provided by a
SwMI, but not directly to a user.
basic (…) service: Any stand alone bearer service or tele-service (derived from ITU-T
Recommendation I.210 [4]).
bearer service: Type of telecommunication service that provides the capability for the transmission of
signals between user-network interfaces (as defined in ITU-T Recommendation I.112 [3]).
busy: Property of a user for whom either a "network determined user busy" or "user determined user
busy" condition (see clause 3.1 of ITU-T Recommendation I.221 [5]) exists.
call, basic call: Instance of the use of a basic service.
call completion: Successful presentation of a previously unsuccessful Call to a destination user (user B)
which occurs when the call has entered an alerting phase or has been answered.
CCNR busy: Any one of the following conditions will cause user A to be considered as CCNR busy:
- maximum number of calls queued at user A;
- CCNR recall pending on user A;
- no resource available at user A.
NOTE 1: It is assumed that SS-CCNR busy is independent from SS-CCBS busy; one could
consider merging the two conditions in an SS-CC busy which would combine the total
numbers of CCBS and CCNR requests.
compatible MS/LS: MS/LS presenting the same basic TETRA class of service as the TETRA class of
service requested by the calling user MS/LS. By analogy to ISDN "compatible terminal".
free: Property of a user who can accept any attempt by the SwMI to present a call to that user (i.e. allow
the call to reach the alerting or answered state).
Line Station (LS): Physical grouping that contains all the fixed equipment that is used to obtain TETRA
services through a line.
Mobile Station (MS):
Physical grouping that contains all of the mobile equipment that is used to obtain
TETRA services. By definition, a mobile station contains at least one Mobile Radio Stack (MRS).
no reply: No reply condition is defined for this ETS as no answer from the called user; the no-answer
time-out has expired. There is no formal definition found in ITU-T, ECMA or ETSI on the terms No Reply.
not reachable:
Different case of no reply; the MS may be out of range or non fed.
path reservation: Reservation of resources just prior to SS-CCNR Recall in order that a connection path
through the network is available when user A accepts the SS-CCNR Recall.

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NOTE 2: Path Reservation would not guarantee that user B will be free when user A accepts the
SS-CCBS Recall.
NOTE 3: Path Reservation is not the preferred mode of operation in the TERA environment due
to mobility considerations.
recall timer: Timer specifies the length of time the network shall wait for a response from user A to a
CCNR Recall.
retention timer: Timer specifies the period of time the network retains the originating call information after
a valid call attempt is released.
SS-CCNR call: Call generated by the network from user A to user B resulting from user A’s acceptance of
a SS-CCNR recall.
SS-CCNR recall: Indication informing user A that user B is now non busy (after a period of no reply, user
B shows some activity and then becomes non-busy). Acceptance of this indication by user A will cause the
call to be completed by the SwMI.
SS-CCNR request: Instance of an activation of SS-CCNR held in a queue pending the correct conditions
for the SS-CCNR to be completed.
SS-CCNR service duration timer: Timer specifies the length of time that the service shall be active
within the network.
supplementary service: Any service provided by a network in addition to its basic service or services
(defined in CCITT Recommendation Q.9 [10]). A supplementary service modifies or supplements a basic
telecommunication service. Consequently, it cannot be offered to a customer as a stand alone service. It
must be offered together with or in association with a basic telecommunication service (except from
ITU-T Recommendation I.210 [4]).
suspended CCNR request: CCNR request that cannot be served even if destination B is not busy,
because user A is busy or CCNR busy.
Switching and Management Infrastructure (SwMI): All of the TETRA equipment for a Voice plus Data
(V+D) network except for subscriber terminals. The SwMI enables subscriber terminals to communicate
with each other via the SwMI.
tele-service: Type of telecommunications service that provides the complete capability, including terminal
equipment functions, for communication between users according to agreed protocols.
User A: Specific user that originated the call and requested the supplementary service.
User B: User that was initially addressed in the original individual call set up.
user B idle guard timer: Time the SwMI will wait after user B has become not busy, after having initiated
an activity before informing user A.
3.2 Symbols
For the purposes of this ETS, there are no special symbols besides the symbols used in SDL diagrams
and defined in ITU-T Recommendation Z.100 [6].

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3.3 Abbreviations
For the purposes of this ETS the following abbreviations apply:
3.3.1 General abbreviations
AI Air Interface
ANF Additional Network Feature
CC Call Control (functional entity)
CC Call Completion (generic term common to both CCBS and CCNR)
ISDN Integrated Services Digital Network
ISI Interworking at the Inter-System Interface
LS Line Station
MS Mobile Station
NRc Not Reachable
PEI Peripheral Equipment Interface
PISN Private Integrated Services Network
SDL Specification and Description Language
SS Supplementary Service
NOTE: The abbreviation SS is only used when referring to a specific supplementary service.
SwMI Switching and Management Infrastructure
V+D Voice Plus Data
3.3.2 Supplementary service abbreviations
AL Ambiance Listening
AoC Advice of Charge
AP Access Priority
AS Area Selection
BIC Barring of Incoming Calls
BOC Barring of Outgoing Calls
CAD Call Authorized by Dispatcher
CCBS Call Completion to Busy Subscriber (TETRA) or Completion of Calls to Busy
Subscriber (ECMA)
CCNR Call Completion on No Reply (TETRA) or Completion of Calls to Busy
Subscriber (ECMA)
CFB Call Forwarding on Busy
CFNRc Call Forwarding on Not Reachable
CFU Call Forwarding Unconditional
CLIP Calling Line Identification Presentation
CLIR Calling/Connected Line Identification Restriction
COLP COnnected Line identification Presentation
CR Call Report
CRT Call ReTention
CW Call Waiting
DGNA Dynamic Group Number Assignment
DL Discreet Listening
HOLD Call Hold
IC Include Call
LE Late Entry
LSC List Search Call
PC Priority Call
PPC Pre-emptive Priority Call
PTN Private Telecommunication Network
SNA Short Number Addressing
TC Transfer of Control
TPI Talking Party Identification

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4 SS-CCNR Stage 1 Specification
4.1 Description
4.1.1 General description
SS-CCNR is offered to a calling user A. On encountering a called user B which, though alerted does not
answer, it allows user A to request that the network monitors user B and notifies user A when user B
becomes free after a subsequent period of activity. On response by user A to that notification, the network
shall attempt to complete the call to user B.
NOTE: User activities that constitute a subsequent period of activity are implementation
specific and beyond the scope of this ETS.
SS-CCNR does not cover the case where the user B's MS is not reachable.
4.1.2 Qualifications on applicability to telecommunication services
This supplementary service is applicable to all basic individual circuit mode TETRA V+D services.
SS-CCNR is not applicable to group calls and is not applicable to SDS.
4.2 Procedures
4.2.1 Provision/Withdrawal
SS-CCNR may be provided after pre-arrangement with the service provider (to selected users), or may be
available generally to all users. SS-CCNR may be withdrawn on request of the user or for administrative
reasons.
No subscription options shall be offered by the SwMI.
NOTE 1: Contrary to ECMA-185 [2] which offers two selection options for recall mode,
SS-CCNR recall shall be offered only to the MS/LS which has invoked SS-CCNR.
NOTE 2: As a guidance to stage 3 ETS, the following main options in relation to ECMA 185 [2]
are selected for TETRA SS-CCNR:
- Path reservation is not provided in a TETRA network.
NOTE 3: In the TETRA network environment, path reservation is deemed not to be necessary
due to mobility considerations; a path reserved between two SwMIs could become not
available when one of the user migrates.
- Signaling connection is retained for the duration of the SS-CCNR request.
- Retention of the SS-CCNR service until expiration of the service duration timer (if user A and/or
user B is found busy after the recall).
4.2.2 Normal Procedures
4.2.2.1 Activation/deactivation/registration/interrogation
SS-CCNR shall be permanently activated upon provision and shall be deactivated upon withdrawal.
Called user B needs not be provided with SS-CCNR for calling user A invocation of SS-CCNR to operate
properly.
Restriction of SS-CCNR for called user B is outside the scope of this ETS.

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NOTE: A mechanism provided to user B which causes rejects of CCNR requests is outside
the scope of this ETS.
Interrogation will not be used to interrogate activation/deactivation status; however, a process similar to
interrogation may be implemented; see invocation clause below.
4.2.2.2 Invocation and operation
When a call from user A fails because the destination user, user B, does not answer, the network shall
retain the call information provided by user A, for a period governed by the retention timer. User A shall be
able to request SS-CCNR during that period. User A shall also be able to request SS-CCNR whilst user B
is alerting.
NOTE 1: User A recognizes that user B does not answer by expiration of the call set-up timer
which is presented to user A in a disconnect with cause expiration of basic call timer.
NOTE 2: User B may not answer the call or may be non reachable.
NOTE 3: Alerting received at user A indicates that user B is reachable.
On receipt of a request for SS-CCNR, the network shall check whether it is possible to initiate the service,
and if so shall send an acknowledgment to user A, start monitoring user B and start the SS-CCNR Service
Duration Timer. The acknowledgment means that user A shall expect to receive a SS-CCNR Recall if
user B becomes not busy, after a subsequent period of activity, within the period of the SS-CCNR Service
Duration Timer.
NOTE 1: The fact that user B is already being monitored, as a result of a call completion request
from another user, shall not cause rejection of the request from user A. The handling
of multiple requests against the same user B is an implementation matter, typically
involving some sort of queue arranged in chronological and/or priority order.
NOTE 2: The fact that user A has already invoked call completion against another user need not
cause rejection of any further requests for call completion from user A. The handling of
multiple requests by the same user A is an implementation matter.
NOTE 3: SS-CCBS requests and SS-CCNR may be dealt with either in a combined manner or
in independent manners; this is an implementation matter.
NOTE 4: Only users for which SS-CCNR has been activated by subscription are allowed to
invoke SS-CCNR for a particular no reply subscriber; users for which SS-CCNR has
not been activated and invoking SS-CCNR will receive a negative response to their
request.
After the SS-CCNR request has been acknowledged, user A shall be able to receive and initiate other
calls.
A network may provide user A with the ability to request a list of outstanding SS-CCNR requests that user
A has invoked. Only details of requests made by user A (and user A only) from that MS/LS should be
provided. The list will be empty if there are no outstanding SS-CCNR requests.
When the monitoring of user B indicates that user B has become free after a period of activity (related to
the same basic service as the original call to user B), and if user A is also free, the network shall provide
SS-CCNR Recall to user A, and start the SS-CCNR Recall timer. The priority of the recall signaling
process shall be equal to the priority of the original call.
If user A accepts the SS-CCNR Recall, the network shall attempt to complete the call between user A and
user B. User A shall not be able to modify the call parameters in the CCNR Call; this holds true for the
basic call setup (such as basic service, priority and area selection) as well as for the supplementary
services invoked for the initial call. If the call is successfully presented to user B and enters an alerting
phase or is answered, SS-CCNR shall be regarded as complete.

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In the case where several invocations of SS-CCNR are in the queue, the calls shall be handled in the
order they occurred unless their priority levels are different in which case the higher priority call shall be
handled first.
To properly operate, SS-CCNR shall be supported by the originating SwMI as well as the terminating
SwMI.
4.2.2.3 Cancellation
The network shall provide user A with the ability to request cancellation of at least one of the following:
- all outstanding SS-CCNR requests for which a SS-CCNR Recall is still expected;
- the most recent SS-CCNR request for which a SS-CCNR Recall is still expected; and
- a specific SS-CCNR request for which a SS-CCNR Recall is still expected.
User A shall be able to cancel its own request(s) and shall not be able to cancel requests from other
users.
User A shall be informed of successful cancellation.
4.2.2.4 Timers
This paragraph regroup
...