SIST ETS 300 284 E1:2003

• Abstract:

  DE/NA-012206

• 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 300 284 ed.1 (1996-03) - Integrated Services Digital Network (ISDN); User-to-User Signalling (UUS) supplementary service; Service description

SIST ETS 300 284 E1:2003 is the Slovenian standard identical to ETS 300 284 Edition 1. It gives the stage 1 service description for the Integrated Services Digital Network (ISDN) User-to-User Signalling (UUS) supplementary service, from the user's point of view. In practice, it tells service providers and ISDN implementers how UUI is requested, activated, transferred, and handled during a call.

What does SIST ETS 300 284 E1:2003 specify?

SIST ETS 300 284 E1:2003 specifies the stage 1 description of the UUS supplementary service for pan-European ISDN. It covers the service as seen by the user, the interworking of private ISDNs with the public ISDN, and the base functionality when the service is provided through a private ISDN.

The standard says UUS is a limited user-to-user information transfer over the signalling channel in association with a call. It applies to circuit-switched telecommunications services. The standard also states that charging principles, the detailed human interface, and interactions with supplementary services not listed in clause 8 are outside its scope.

The document is organized into the following main clauses: scope, normative references, definitions, symbols and abbreviations, description, procedures, intercommunication considerations, and interaction with other supplementary services. Annex A is informative and gives interaction details for call deflection and call forwarding no reply.

Annex	What it covers
Annex A	Interaction between UUS and call deflection after alerting, and call forwarding no reply

A key point for readers is that SIST ETS 300 284 E1:2003 is a service description, not a test standard. The foreword says conformance is met by conforming to the stage 3 standard for the relevant equipment, so this document itself does not provide a test method.

What are the key requirements of SIST ETS 300 284 E1:2003?

SIST ETS 300 284 E1:2003 sets out how UUS works, when it can be used, and what the network must do with UUI. The most important points are the service access conditions, the three service variants, the activation rules, and the interaction with other call services.

Service access and UUI handling

Clause 5 says UUS shall be available to users connected via a basic access or a primary rate access. The network must pass UUI transparently, without changing its content or interpreting it. In practice, this means the network acts as a transport path for signalling information, not as an application layer.

The three service forms

Clause 5 defines service 1, service 2, and service 3 by the phase of the call in which UUI may be transferred. Service 1 allows UUI during call origination and termination, service 2 allows UUI after the called user is being informed and before connection, and service 3 allows UUI only after connection is established. For implementers, the service form determines when sending and receiving UUI is permitted.

Provision, withdrawal, activation, and requests

Clause 6 says the service is provided only after prior arrangement with the service provider, and the remote user does not need a subscription. The service may be offered as service 1 implicit request, service 1 implicit and explicit request together, service 2, service 3, or combinations of these. Service 1 can be requested implicitly or explicitly, while service 2 and service 3 require explicit request. The document also defines “UUS required” and “UUS not required” requests, which matter when the caller wants the call to proceed only if UUI can be passed.

Message size and service 3 flow control

Clause 5 says service 1, service 2, and service 3 allow 128 octets per message. Clause 6.2.3.3 adds network flow control for service 3 after the connection is established, with burst parameter X = 16, replenishment parameter Y = 8, and replenishment intervals of T = 10 seconds. This means implementations must control the rate of UUI messages and discard excess traffic rather than queueing it indefinitely.

Interworking and call-level behavior

Clause 7 states that only requests supported on both networks are transferred to the other user. It also covers interworking with non-ISDNs, where UUI can be delivered only if the non-ISDN has a way to convey it, and with private ISDNs, where the public network considers its task complete once UUI is delivered to the private ISDN. For international calls, the same flow-control values apply. This matters when systems cross network boundaries, because unsupported service requests are rejected rather than partially passed.

Interaction with other supplementary services

Clause 8 describes how UUS behaves with call waiting, explicit call transfer, diversion services, conference services, terminal portability, and three party. For example, explicit call transfer cancels UUS on the resulting call, terminal portability is not compatible because UUI cannot be transferred while a call is suspended, and during a three party call UUI can be exchanged separately with each remote party but not between those remote parties. Annex A gives a detailed interaction table for call forwarding no reply and call deflection.

What terms does SIST ETS 300 284 E1:2003 define?

SIST ETS 300 284 E1:2003 defines the terms needed to use the service description precisely.

• User-to-User Information (UUI) - the information transferred by using UUS.
• User-to-User Signalling (UUS) - the supplementary service that transfers UUI between users associated with a call.
• Service 1 - UUI can be sent and received during call origination and termination.
• Service 2 - UUI can be sent and received after the called user is being informed and before connection.
• Service 3 - UUI can be sent and received only while the connection is established.
• Explicit request - the user has asked for activation of UUS.
• Implicit request - UUI is sent when originating a call without an explicit service request.
• Served user - the user to whom the UUS supplementary service is provided and who requests activation.

These definitions matter because the same call can behave differently depending on whether the request is implicit or explicit, and which service form is active.

Who uses SIST ETS 300 284 E1:2003?

SIST ETS 300 284 E1:2003 is used by telecommunications service providers, ISDN network designers, switch and signalling engineers, and product teams implementing ISDN supplementary services. It is also useful for quality managers and buyers who need to check whether an ISDN solution supports UUS in the expected call phases and interworking situations.

In practice, users of the standard use it to decide how UUI is offered to subscribers, how network nodes should respond to activation and rejection, and how UUS behaves when calls are forwarded, deflected, transferred, or placed in conference. It is most relevant where public ISDN and private ISDN interwork.

Which standards are used with SIST ETS 300 284 E1:2003?

SIST ETS 300 284 E1:2003 relies on several CCITT recommendations for its terminology and service model.

• CCITT Recommendation I.130 - defines the three-stage method for characterizing ISDN services and network capabilities; this is the framework used by the standard.
• CCITT Recommendation I.112 - provides the vocabulary of ISDN terms.
• CCITT Recommendation I.210 - gives the principles of ISDN telecommunication services and how to describe them.
• CCITT Recommendation Q.9 - provides switching and signalling vocabulary, including access terms used in the definitions.
• ETR 285 - gives the stage 2 aspects of the UUS supplementary service.
• ETS 300 286 - gives the stage 3 aspects of the UUS supplementary service.

These references matter because this document is only the stage 1 service description; the functional capabilities and signalling details are defined in the companion stage 2 and stage 3 documents.

What does the SIST ETS 300 284 E1:2003 document contain?

SIST ETS 300 284 E1:2003 contains a clause-by-clause service description, not implementation code or test procedures. It describes the service, the activation and deactivation paths, normal and exceptional procedures, and the handling of UUI during call setup, established calls, and call release.

The document also includes detailed intercommunication considerations and a long interaction section covering call waiting, explicit call transfer, diversion services, conference services, terminal portability, and three party. Annex A adds a practical interaction table for call forwarding no reply and call deflection, which is useful when checking network behavior at call routing boundaries.

The foreword records that this ETS is a stage 1 service description in the I.130 framework. It also notes that stage 2 and stage 3 are covered in separate companion documents, so this standard is mainly the service reference for planning, implementation checks, and interworking analysis.

SLOVENSKI STANDARD
01-december-2003
Digitalno omrežje z integriranimi storitvami (ISDN) – Dopolnilna storitev:
meduporabniška signalizacija (UUS) – Opis storitve
Integrated Services Digital Network (ISDN); User-to-User Signalling (UUS)
supplementary service; Service description
Ta slovenski standard je istoveten z: ETS 300 284 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 300 284
TELECOMMUNICATION March 1996
STANDARD
Source: ETSI TC-NA Reference: DE/NA-012206
ICS: 33.080
ISDN, supplementary service
Key words:
Integrated Services Digital Network (ISDN);
User-to-User Signalling (UUS) 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 1996. All rights reserved.

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ETS 300 284: March 1996
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 300 284: March 1996
Contents
Foreword .5
1 Scope .7
2 Normative references.7
3 Definitions.8
4 Symbols and abbreviations .9
5 Description .9
6 Procedures.10
6.1 Provision and withdrawal .10
6.2 Normal procedures .10
6.2.1 Activation, deactivation and registration.10
6.2.1.1 Service 1.11
6.2.1.2 Service 2.11
6.2.1.3 Service 3.12
6.2.1.4 "UUS required" request .12
6.2.2 Erasure.12
6.2.3 Invocation and operation .12
6.2.3.1 Service 1.12
6.2.3.2 Service 2.12
6.2.3.3 Service 3.13
6.2.4 Interrogation .13
6.3 Exceptional procedures .13
6.3.1 Activation, deactivation and registration.13
6.3.2 Erasure.13
6.3.3 Invocation and operation .14
6.3.4 Interrogation .14
7 Intercommunication considerations.14
7.1 Interworking with non-ISDNs .14
7.2 Interworking with private ISDNs.14
8 Interaction with other supplementary services .15
8.1 Advice of charge services.15
8.1.1 Charging information at call set-up time.15
8.1.2 Charging information during the call.15
8.1.3 Charging information at the end of the call.15
8.2 Call waiting.15
8.3 Call hold .15
8.4 Explicit call transfer.15
8.5 Number identification services.15
8.5.1 Calling line identification presentation .15
8.5.2 Calling line identification restriction .15
8.5.3 Connected line identification presentation.15
8.5.4 Connected line identification restriction.16
8.6 Closed user group.16
8.7 Completion of calls to busy subscriber .16
8.8 Conference services .16
8.8.1 Conference call add-on .16
8.8.2 Meet-me conference .17
8.9 Direct dialling in.17
8.10 Diversion services.17

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8.10.1 Call forwarding unconditional. 17
8.10.2 Call forwarding busy . 17
8.10.3 Call forwarding no reply . 17
8.10.4 Call deflection . 18
8.10.4.1 Request for the call deflection supplementary service in
response to the offered call. 18
8.10.4.2 Request for the call deflection supplementary service
during the period that the user is being informed of the
incoming call . 19
8.10.4.3 After deflection . 19
8.11 Freephone. 20
8.12 Malicious call identification. 20
8.13 Multiple subscriber number . 20
8.14 Subaddressing . 20
8.15 Terminal portability. 20
8.16 Three party. 20
8.17 User-to-user signalling . 20
Annex A (informative): Interaction between the UUS supplementary service and the call deflection
(after alerting) and the call forwarding no reply supplementary services. 21
History. 22

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ETS 300 284: March 1996
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 User-to-User Signalling (UUS)
supplementary service. Stage 2 and stage 3 aspects are detailed in ETR 285 (1996) and
ETS 300 286 (1996) respectively.
Transposition dates
Date of adoption of this ETS: 1 March 1996
Date of latest announcement of this ETS (doa): 30 June 1996
Date of latest publication of new National Standard
or endorsement of this ETS (dop/e): 31 December 1996
Date of withdrawal of any conflicting National Standard (dow): 31 December 1996

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1 Scope
This standard defines the stage one of the User-to-User Signalling (UUS) 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.
Charging principles are outside the scope of this standard.
Interaction with supplementary services not listed in clause 8 are outside the scope of this standard.
The UUS supplementary service enables a user to send/receive a limited amount of information to/from
another user over the signalling channel in association with a call to the other user.
The UUS supplementary service is applicable to all circuit-switched telecommunications services.
This standard is applicable to the stage two and the stage three standards for the ISDN UUS
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
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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3 Definitions
For the purposes of this standard, the following definitions apply:
"UUS not required" request: a request where originating a call shall continue even if the request for the
UUS supplementary service cannot be accepted.
"UUS required" request: a request where originating a call shall be rejected if the request for the UUS
supplementary service cannot be accepted.
Basic access: see CCITT recommendation Q.9 [4], § 1, definition 1552.
Called user: the user who received an incoming call (originated by the calling user).
Calling user: the user who originates, or originated, the call.
Explicit request: the UUS supplementary service is considered as explicitly requested when a user
requests the activation of the UUS supplementary service.
Implicit request: the UUS supplementary service is considered as implicitly requested when no explicit
request for the UUS supplementary service is made and UUI is sent by the user when originating a call.
Integrated Services Digital Network (ISDN): see CCITT Recommendation I.112 [2], § 2.3, definition
308.
Point-to-multipoint configuration: a situation where multiple responses to an incoming call can occur.
Point-to-point configuration: a situation where multiple responses to an incoming call cannot occur.
Primary rate access: see CCITT recommendation Q.9 [4], § 1, definition 1552.
Remote user: the user who receives a request for activation of the UUS supplementary service.
Basic service; telecommunications service: see CCITT Recommendation I.112 [2], § 2.2, definition
201.
Served user: the user to whom the UUS supplementary service is provided and who requests the
activation of the UUS supplementary service.
Service 1: a form of the UUS supplementary service where UUI can be sent and received during the
origination and termination of calls.
Service 2: a form of the UUS supplementary service where UUI can be sent and received after the calling
user has received an indication that the called user is being informed of the call and prior to the
establishment of the connection.
Service 3: a form of the UUS supplementary service where UUI can be sent and received only while the
connection is established.
Supplementary service: see CCITT Recommendation I.210 [3], § 2.4.
User-to-User Information (UUI): the information transferred by using the UUS supplementary service.

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4 Symbols and abbreviations
ISDN Integrated Services Digital Network
ISUP ISDN User Part
UUI User-to-User Information
UUS User-to-User Signalling
5 Description
The UUS supplementary service shall be available to users who are connected to a network via a basic
access or a primary rate access.
The UUS supplementary service enables a user to send/receive a limited amount of information to/from
another user over the signalling channel in association with a call to the other user. This information shall
be passed transparently (i.e. without modification of contents) through the network. The network shall not
interpret or act upon this information.
The user can transfer UUI in different phases of the call depending on the service(s) to which the user
subscribes. These services are:
- service 1:
UUI can be sent and received during the origination and termination of calls.
In the case of a point-to-multipoint configuration at the called user, the following restrictions shall
apply to the transfer of UUI:
- in the forward direction: UUI can be sent by the calling user only as part of the request for the
origination of a call, or as part of the request to terminate the call. If the calling user
terminates the call prior to the connection being established, UUI shall only be delivered to
those terminals which have indicated that the user has been informed of the call;
- in the backward direction: UUI can be sent from the called user to the calling user with the
indication that the called user is being informed of the call. It shall be the called user's
responsibility to avoid contention. UUI can also be sent from the called user when answering
the call;
- if the called user rejects the call and the network receives a single rejection from the called
user, then the reason for rejection and the accompanying UUI (if any) shall be sent to the
calling user.
- If the network receives multiple rejections from the called user, with the same or differing
reasons for rejection, then the network shall select the first received, highest priority rejection
(based upon the reason(s) for rejection). The reason for rejection and the accompanying UUI
(if any) of the selected rejection shall be sent to the calling user.
- service 2:
UUI can be sent and received after the calling user has received an indication that the called user is
being informed of the call and prior to the establishment of the connection. UUI sent by the calling
user prior to receiving the acceptance of the call by the called user may, as a service provider
option, be delivered to the called user after the call has been established.
Service 2 is only applicable if a point-to-point configuration exists at the called user's side;

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- service 3:
UUI can be sent and received only while the connection is established.
Service 1, service 2 and service 3 shall allow the transmission of 128 octets per message.
NOTE: During an interim period of time, some service providers may support the transfer of
only 32 octets of UUI on service 1.
Limitations are also placed on the number of messages per time unit for service 3. The flow control of
each direction shall operate independently.
6 Procedures
6.1 Provision and withdrawal
The UUS supplementary service shall be provided to the user after prior arrangement with the service
provider. No subscription is required for the remote user.
As a service provider option, one or any combination of the following can be provided:
- service 1 implicit request, or service 1 implicit request together with service 1 explicit request;
- service 2;
- service 3.
The UUS supplementary service shall be withdrawn by the service provider upon request of the subscriber
or for service provider reasons.
As a service provider option, withdrawal can be done separately per service provided, or globally for all
services provided to the served user.
6.2 Normal procedures
6.2.1 Activation, deactivation and registration
The UUS supplementary service is activated when:
- it is implicitly requested (for service 1); or
- it is explicitly requested (for service 1, service 2 and service 3) and accepted by the remote user.
Depending on the served user's subscription to the UUS supplementary service and the provision of the
UUS supplementary service by the service provider, service 1 implicit, service 1 explicit, service 2 and
service 3 can be activated individually or in combination. Service 1 implicit and service 1 explicit cannot be
simultaneously active.
Once a service is activated (i.e. service 1 and/or service 2 and/or service 3) the network shall accept UUI
from either user in the call, according to the service that has been activated.
The UUS supplementary service requires no registration.

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6.2.1.1 Service 1
Service 1 shall be requested by the calling user when originating a call, if UUI transfer is desired in either
direction.
Service 1 can be activated by means of an implicit request or an explicit request. Service 1 is implicitly
requested when UUI is included when originating a call. The served user shall be given an explicit
response (acceptance or rejection) to an explicit request. An explicit request can include UUI.
When service 1 is explicitly requested, the network shall inform the remote user of the request. The
network shall interrogate for the availability of the UUS supplementary service of the remote user. No
response from the remote user shall be taken by the network as a rejection of the request for the UUS
supplementary service. The network shall explicitly indicate to the served user whether or not the
requested service has been successfully activated.
When service 1 is explicitly requested, the remote user can include UUI when accepting the request for
the UUS supplementary service.
When service 1 is implicitly requested, service 1 is active for the call, i.e. the remote user is not required to
send a response to the implicit request. However, the remote user can include UUI in the call response
(e.g. for user-to-user negotiation).
Service 1 is automatically deactivated when the call is terminated.
6.2.1.2 Service 2
Service 2 shall be requested by the calling user when originating a call, if UUI transfer is desired in either
direction.
Service 2 shall be explicitly requested. The served user shall be given an explicit response (acceptance or
rejection) to an explicit request.
For service 2 the network shall confirm the request for the UUS supplementary service. This confirmation
shall be preceded by an end-to-end check by the network for service availability. The network shall
interrogate for the availability of the UUS supplementary service of the remote user. No response from the
remote user shall be taken by the network as a rejection of the request for the UUS supplementary
service. The network shall explicitly indicate to the served user whether or not the requested service has
been successfully activated.
Service 2 is automatically deactivated when the called user is no longer being informed of the call.

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6.2.1.3 Service 3
The calling user can request the activation of service 3 when a call is originated or after the connection
has been established. As a service provider option, the called user can request the activation of service 3
after the connection has been established. The calling user shall accept this request fo
...