SIST ETS 300 186 E1:2003

• Abstract:

  T/NA1(89)28

• Status: Published
• Publication Date: 30-Nov-2003
• 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 300 186 ed.1 (1993-07) - Integrated Services Digital Network (ISDN); Three-Party (3PTY) supplementary service; Service description

SIST ETS 300 186 E1:2003 is the Slovenian adoption of ETS 300 186 Edition 1 from ETSI. It gives the stage 1 service description for the Integrated Services Digital Network (ISDN) Three-Party (3PTY) supplementary service, defining how a served user can set up and control a three-way conversation. It is written for public ISDN operators and for people implementing, configuring, or checking the service.

What does SIST ETS 300 186 E1:2003 specify?

SIST ETS 300 186 E1:2003 specifies the stage one, or overall user-level description, of the ISDN 3PTY supplementary service. It focuses on service behavior and interworking, not on the human interface details or on charging principles.

The document is organized into clauses for scope, normative references, definitions, symbols and abbreviations, description, procedures, intercommunication considerations, and interaction with other supplementary services. Annex A is informative and explains how active and held calls are managed when a user has more than one call.

Annex	What it covers
A	Management of active and held calls for a user controlling more than one call

What are the key requirements of SIST ETS 300 186 E1:2003?

Service access and use

SIST ETS 300 186 E1:2003 says the 3PTY supplementary service shall be available to users connected through a basic access or a primary rate access. A served user can invoke it only when already involved in at least two established calls, with one active call and at least one held call.

In practice, this means the service is not started from an idle state. The user must first have two connected calls ready, so implementation and customer instructions need to support hold, retrieve, and then 3PTY invocation.

Creating and controlling a three-way conversation

SIST ETS 300 186 E1:2003 allows the served user to join the active call and the held call into a three-way conversation. Once the conversation is active, the served user can disconnect one remote party, end the whole conversation, or move one party into private communication while the other call remains held.

This matters because the service is not just a conference join function - it also defines how the conversation is split, how calls remain connected, and how the service terminates automatically after those actions.

Notifications and rejection handling

SIST ETS 300 186 E1:2003 requires the served user and the remote parties to be informed when the 3PTY service is invoked and when it ends. If the service cannot be provided, the request shall be rejected with a reason, such as no subscription, lack of resources, or calls not being in the right state.

For operators, this means the network must present clear feedback and must leave the existing calls unchanged when a request is rejected.

Interworking and network boundaries

SIST ETS 300 186 E1:2003 covers interworking with non-ISDNs and private ISDNs. It allows the remote parties to be on other networks, and it notes that indications may need to be forwarded across network boundaries. It also states that two three-way conversations in different networks can be connected together, with the served user in one becoming a remote party in the other.

This is important for service design across mixed networks, where signaling and user notifications may not behave exactly the same as inside a single public ISDN.

Interaction with other supplementary services

SIST ETS 300 186 E1:2003 describes how 3PTY interacts with services such as call hold, explicit call transfer, conference services, terminal portability, closed user group, number identification services, and user-to-user signalling. Some combinations are allowed, while others require the served user to end 3PTY first.

In practice, implementers need to check service combinations carefully, because the behavior depends on which supplementary service is being invoked and by whom.

What terms does SIST ETS 300 186 E1:2003 define?

• Integrated Services Digital Network (ISDN) - The digital network environment in which the service is provided, using the CCITT Recommendation I.112 definition.
• Served user - The user to whom the 3PTY supplementary service is provided and who invokes it.
• Remote party - Any user in the call other than the served user; there are two remote parties in a three-way conversation.
• Three-way conversation - Communication among the served user and both remote parties at the same time.
• Private communication - Communication between the served user and one remote party only, excluding the other remote party.
• Basic access - An ISDN access type referenced from CCITT Recommendation Q.9.
• Primary rate access - Another ISDN access type referenced from CCITT Recommendation Q.9.

Who uses SIST ETS 300 186 E1:2003?

SIST ETS 300 186 E1:2003 is used by public telecommunications operators, ISDN service providers, and network engineers who design or configure supplementary services. It is also relevant to implementers of private ISDNs that interwork with the public ISDN, because the document defines how 3PTY behaves across network boundaries.

Quality managers and testers use it to check that the service behavior matches the stage 1 description before comparing implementation against the stage 3 protocols and switching functions.

What changed in SIST ETS 300 186 E1:2003 from the previous edition?

SIST ETS 300 186 E1:2003 is identified as identical to ETS 300 186 Edition 1. The history records the first edition as July 1993 and notes a February 1996 conversion into PDF format.

Which standards are used with SIST ETS 300 186 E1:2003?

• CCITT Recommendation I.130 - Provides the three-stage model used to describe ISDN supplementary services.
• CCITT Recommendation I.112 - Supplies ISDN vocabulary used for core terms such as ISDN and telecommunications service.
• CCITT Recommendation I.210 - Gives the principles for telecommunication services supported by an ISDN and how to describe them.
• CCITT Recommendation Q.9 - Provides switching and signalling vocabulary used for access terms and related definitions.

What does the SIST ETS 300 186 E1:2003 document contain?

The document contains a stage 1 description of the 3PTY service, followed by procedural text for provision, invocation, operation, and exceptional handling. It also explains intercommunication with non-ISDNs and private ISDNs, then gives service interaction rules for other supplementary services.

Annex A adds guidance on managing active and held calls when a user has more than one call in progress. That annex is useful for understanding the call control actions that sit around 3PTY, even though it is informative rather than mandatory.

SLOVENSKI STANDARD
01-december-2003
Digitalno omrežje z integriranimi storitvami (ISDN) – Dopolnilna storitev:
konferenca treh (3PTY) – Opis storitve
Integrated Services Digital Network (ISDN); Three-Party (3PTY) supplementary service;
Service description
Ta slovenski standard je istoveten z: ETS 300 186 Edition 1
ICS:
33.080 Digitalno omrežje z Integrated Services Digital
integriranimi storitvami Network (ISDN)
(ISDN)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN ETS 300 186
TELECOMMUNICATION July 1993
STANDARD
Source: ETSI TC-NA Reference: T/NA1(89)28
ICS: 33.080
ISDN, supplementary service
Key words:
Integrated Services Digital Network (ISDN);
Three-Party (3PTY) supplementary service
Service description
ETSI
European Telecommunications Standards Institute
ETSI Secretariat
F-06921 Sophia Antipolis CEDEX - FRANCE
Postal address:
650 Route des Lucioles - Sophia Antipolis - Valbonne - FRANCE
Office address:
c=fr, a=atlas, p=etsi, s=secretariat - [e-mail]
X.400: Internet:
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 1993. All rights reserved.
New presentation - see History box

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ETS 300 186: July 1993
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 Editing and Committee Support Dept." at the address shown on the title page.

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ETS 300 186: July 1993
Contents
Foreword .5
1 Scope .7
2 Normative references.7
3 Definitions.8
4 Symbols and abbreviations .8
5 Description .8
6 Procedures.9
6.1 Provision and withdrawal .9
6.2 Normal procedures .9
6.2.1 Activation, deactivation and registration.9
6.2.2 Erasure.9
6.2.3 Invocation and operation .9
6.2.3.1 Beginning the 3PTY supplementary service.9
6.2.3.2 Managing the three-way conversation.9
6.2.3.3 Actions available to the remote parties.9
6.2.3.4 Information provided to participants .10
6.2.4 Interrogation .10
6.3 Exceptional procedures .10
6.3.1 Activation, deactivation and registration.10
6.3.2 Erasure.10
6.3.3 Invocation and operation .10
6.3.4 Interrogation .10
7 Intercommunication considerations.10
7.1 Interworking with non-ISDNs .10
7.2 Interworking with private ISDNs.11
8 Interaction with other supplementary services .11
8.1 Advice of charge services.11
8.1.1 Charging information at call set-up time.11
8.1.2 Charging information during the call.11
8.1.3 Charging information at the end of the call.11
8.2 Call waiting.12
8.3 Call hold .12
8.4 Explicit call transfer.12
8.5 Number identification services.12
8.5.1 Calling line identification presentation .12
8.5.2 Calling line identification restriction .12
8.5.3 Connected line identification presentation.12
8.5.4 Connected line identification restriction.12
8.6 Closed user group.12
8.7 Completion of calls to busy subscriber .12
8.8 Conference services .13
8.8.1 Conference call, add-on .13
8.8.2 Meet-me conference .13
8.9 Direct dialling in.13
8.10 Diversion services.13
8.10.1 Call forwarding unconditional .13
8.10.2 Call forwarding busy.13
8.10.3 Call forwarding no reply.13

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ETS 300 186: July 1993
8.10.4 Call deflection . 13
8.11 Freephone. 13
8.12 Malicious call identification. 14
8.13 Multiple subscriber number . 14
8.14 Subaddressing . 14
8.15 Terminal portability. 14
8.16 Three-party. 14
8.17 User-to-user signalling . 14
Annex A (informative): Management of active and held calls . 15
A.1 Introduction. 15
A.2 Functionality available to the served user controlling more than one call. 15
History. 16

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ETS 300 186: July 1993
Foreword
This European Telecommunication Standard (ETS) has been produced by the Network Aspects (NA)
Technical Committee of the European Telecommunications Standards Institute (ETSI).
In accordance with CCITT Recommendation I.130 [1], the following three level structure is used to
describe the supplementary telecommunications services as provided by European public
telecommunications operators under the pan-European Integrated Services Digital Network (ISDN):
- Stage 1: is an overall service description, from the user's standpoint;
- Stage 2: identifies the functional capabilities and information flows needed to support the
service described in stage 1; and
- Stage 3: defines the signalling system protocols and switching functions needed to implement
the service described in stage 1.
This ETS details the stage 1 aspects (overall service description) for the Three-Party (3PTY)
supplementary service. Stage 2 and stage 3 aspects are detailed in ETS 300 187 (1993) and
ETS 300 188 (1993) respectively.

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ETS 300 186: July 1993
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ETS 300 186: July 1993
1 Scope
This standard defines the stage one of the Three-Party (3PTY) supplementary service for the
pan-European Integrated Services Digital Network (ISDN) as provided by European public
telecommunications operators. Stage one is an overall service description from the user's point of view
(see CCITT Recommendation I.130 [1]), but does not deal with the details of the human interface itself.
This standard defines the interworking requirements of private ISDNs with the public ISDN.
In addition, this standard specifies the base functionality where the service is provided to the user via a
private ISDN.
This standard does not specify the additional requirements where the service is provided to the user via a
telecommunications network that is not an ISDN but does include interworking requirements of other
networks with the public ISDN.
Interaction with supplementary services not listed in Clause 8 are outside the scope of this standard.
Charging principles are outside the scope of this standard.
The 3PTY supplementary service enables a user to establish, participate in and control, a three-way
conversation, i.e. a simultaneous communication involving the served user and two remote parties.
The 3PTY supplementary service is applicable to all circuit-switched telecommunications services carrying
speech.
This standard is applicable to the stage two and the stage three standards for the ISDN 3PTY
supplementary service. The terms "stage two" and "stage three" are also defined in CCITT
Recommendation I.130 [1]. Where the text indicates the status of a requirement (i.e. as strict command or
prohibition, as authorisation leaving freedom, or as a capability or possibility), this shall be reflected in the
text of the relevant stage two and stage three standards.
Furthermore, conformance to this standard is met by conforming to the stage three standard with the field
of application appropriate to the equipment being implemented. Therefore, no method of testing is
provided for this standard.
2 Normative references
This standard incorporates, by dated or 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 standard only when incorporated in it by amendment or revision. For undated references the
latest edition of the publication referred to applies.
[1] CCITT Recommendation I.130 (1988): "Method for the characterisation of the
telecommunication services supported by an ISDN and network capabilities of
an ISDN".
[2] CCITT Recommendation I.112 (1988): "Vocabulary of terms for ISDNs".
[3] CCITT Recommendation I.210 (1988): "Principles of telecommunication
services supported by an ISDN and the means to describe them".
[4] CCITT Recommendation Q.9 (1988): "Vocabulary of switching and signalling
terms".
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ETS 300 186: July 1993
3 Definitions
For the purpose of this standard, the following definitions apply:
Integrated Services Digital Network (ISDN): see CCITT Recommendation I.112 [2], § 2.3, definition
308.
Service; telecommunications service: see CCITT Recommendation I.112 [2], § 2.2, definition 201.
Supplementary service: see CCITT Recommendation I.210 [3], § 2.4.
Served user: the user to whom the 3PTY supplementary service is provided and who invokes the 3PTY
supplementary service.
Remote party: a user involved in a call, other than the served user.
NOTE: Whilst two calls are connected in a three-way conversation, there are two remote
parties involved.
Basic access: see CCITT Recommendation Q.9 [4], § 1, definition 1551.
Primary rate access: see CCITT Recommendation Q.9 [4], § 1, definition 1552.
Three-way conversation: communication between all three users, i.e. the served user and both remote
parties.
Private communication: communication between the served user and one remote party. This excludes
communication with the other remote party.
4 Symbols and abbreviations
3PTY Three-Party
ISDN Integrated Services Digital Network
5 Description
The 3PTY supplementary service shall be available to users who are connected to the network via a basic
access or a primary rate access.
The 3PTY supplementary service enables a user to establish, participate in and control, a three-way
conversation.
The 3PTY supplementary ser
...