ISO/IEC 14845:1996
(Main)Information technology — Telecommunications and information exchange between systems — Private Integrated Services Network — Specification, functional model and information flows — Call intrusion supplementary service
Information technology — Telecommunications and information exchange between systems — Private Integrated Services Network — Specification, functional model and information flows — Call intrusion supplementary service
Technologies de l'information — Télécommunications et échange d'information entre systèmes — Réseau privé à intégration de services — Spécification, modèle fonctionnel et débit d'information — Service supplémentaire d'intrusion d'appel
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lSO/IEC
INTERNATIONAL
14845
STANDARD
First edition
1996-09-I 5
Information technology -
Telecommunications and information
exchange between systems - Private
Integrated Services Network -
Specification, functional model and
information flows - Call intrusion
supplementary service
Technologies de I ‘information - TMcommunica tions et khange
Rkseau priv6 ;j in tggration de services -
d ‘informa tion en tre sys t&mes -
Spkification, mod&/e fonctionnel et dkbit d’information - Service
suppkmentaire d/intrusion d’appel
Reference number
GO/I EC 14845: 1996(E)
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ISO/IEC 148451996 (E)
Contents
iv
Foreword
V
Introduction
1
1 Scope
1
2 Conformance
1
3 Normative references
2
4 Definitions
2
4.1 External definitions
3
4.2 Other definitions
4
5 List of acronyms
5
6 SS-CI stage 1 specification
5
6.1 Description
5
6.1.1 General description
5
6.1.2 Qualifications on applicability to telecommunication services
5
6.2 Procedures
5
6.2.1 Provision/withdrawal
5
6.2.2 Normal procedures
8
6.2.3 Exceptional procedures
8
6.3 Interactions with other supplementary services and ANFs
8
6.3.1 Calling Line Identification Presentation (SS-CLIP)
8
6.3.2 Connected Line Identification Presentation (SS-COLP)
8
6.3.3 Calling/Connected Line Identification Restriction (SS-CLIR)
8
6.3.4 Calling Name Identification Presentation (SS-CNIP)
8
6.3.5 Connected Name Identification Presentation (SS-CONP)
9
6.3.6 Calling/Connected Name Identification Restriction (SS-CNIR)
9
6.3.7 Completion of Calls to Busy Subscriber (SS-CCBS)
9
6.3.8 Completion of Calls on No Reply (SS-CCNR)
9
6.3.9 Call Transfer (SS-CT)
9
6.3.10 Call Forwarding Unconditional (SS-CFU)
9
6.3.11 Call Forwarding Busy (SS-CFB)
9
6.3.12 Call Forwarding No Reply (SS-CFNR)
10
6.3.13 Call Deflection (SS-CD)
10
6.3.14 Path Replacement (ANF-PR)
10
6.3.15 Do Not Disturb (DND)
10
6.3.16 Do Not Disturb Override (DNDO)
10
6.3.17 Call Offer (CO)
10
6.4 Interworki ng cons iderations
0 ISO/IEC 1996
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mission in writing from the publisher.
ISO/IEC Copyright Office * Case Postale 56 * CH-1211 Geneve 20 * Switzerland
Printed in Switzerland
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ISOAEC 14845:1996 (E)
OISO/IEC
10
6.5 Overall SDL
19
7 SS-CI stage 2 specification
19
7.1 Functional model
19
7.1.1 Functional model description
20
7.1.2 Description of functional entities
21
7.1.3 Relationship of functional model to basic call functional model
21
7.2 Information flows
21
7.2.1 Definition of information flows
27
7.2.2 Relationship of information flows to basic call information flows
30
7.2.3 Examples of information flow sequences
40
7.3 Functional entity actions
40
7.3.1 Functional entity actions of FE1
41
7.3.2 Functional entity actions of FE2
42
7.3.3 Functional entity actions of FE3
43
7.3.4 Functional entity actions of FE4
43
7.3.5 Functional entity actions of FE5
43
7.4 Functional entity behaviour
43
7.4.1 Behaviour of FE1
52
7.4.2 Behaviour of FE2
62
7.4.3 Behaviour of FE3
70
7.4.4 Behaviour of FE4
71
7.4.5 Behaviour of FE5
72
7.5 Allocation of functional entities to physical equipment
72
7.6 Interworking considerations
. . .
111
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ISO/IEC 14845:1996 (E) OISO/IEC
Foreword
IS0 (the International Organization for Standardization) and IEC (the International Electrotechnical Commission) form the
specialized system for worldwide standardization. National bodies that are members of IS0 or IEC participate in the
development of International Standards through technical committees established by the respective organization to deal with
particular fields of technical activity. IS0 and IEC technical committees collaborate in fields of mutual interest. Other
international organizations, governmental and non-governmental, in liaison with IS0 and IEC, also take part in the work.
In the field of information technology, IS0 and IEC have established a joint technical committee, ISO/IEC JTC 1. Draft
International Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75% of the national bodies casting a vote.
International Standard ISOLIEC 14845 was prepared by ECMA (as Standard ECMA-202) and was adopted, under a special
“fast-track procedure”, by Joint Technical Committee ISO/IEC JTC 1, Infomzation technology, in parallel with its approval
by national bodies of IS0 and IEC.
iv
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OISOLIEC
ISO/IFX 14845: 1996 (E)
Introduction
This International Standard is one of a series of International Standards defining services and signalling protocols applicable to
Private Integrated Services Networks (PISNs). The series uses ISDN concepts as developed by ITU-T and conforms to the
framework of International Standards for Open Systems Interconnection as defined by ISO/IEC.
This particular International Standard specifies the Call Intrusion supplementary service.
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ISOIIEC 14845:1996 (E)
INTERNATIONAL STANDARD @ ISWIEC
Information technology - Telecommunications and information exchange between
systems - Private Integrated Services Network - Specification, functional model and
information flows - Call intrusion supplementary service
1 Scope
This International Standard specifies the Call Intrusion supplementary service (SS-CI), which is applicable to various basic
services supported by Private Integrated Services Networks (PISN). Basic services are specified in ISO/IEC 11574.
Call Intrusion (SS-CI) is a supplementary service which, on request from the served user, enables the served user to establish
communication with a busy called user (user B) by breaking into an established call between user B and a third user (user
.
C>
Supplementary service specifications are produced in three stages, according to the method described in CCITT
Recommendation I. 130. This International Standard contains the stage 1 and stage 2 specifications of SS-CI. The stage 1
specification (clause 6) specifies the supplementary service as seen by users of PISNs. The stage 2 specification (clause 7)
identifies the functional entities involved in the supplementary service and the information flows between them.
Note - For this International Standard, stage 2 does not consider the split of functionality between a functional terminal at user B and the local PINX. Terminal
functions and local PINX functions at user B are included in the same Functional Entity.
2 Conformance
In order to conform to this International Standard, a stage 3 International Standard shall specify signalling protocols and
equipment behaviour that are capable of being used in a PISN which supports the supplementary service specified in this
International Standard. This means that, to claim conformance, a Stage 3 International Standard is required to be adequate
for the support of those aspects of clause 6 (stage 1) and clause 7 (stage 2) which are relevant to the interface or equipment
to which the Stage 3 International Standard applies.
3 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions of this International
Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to
agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent
editions of the standards indicated below. Members of IEC and IS0 maintain registers of currently valid International
Standards.
ISO/IEC 11571:1994, Information technology - Telecommunications and information exchange between systems -
Numbering and sub-addressing in private integrated services networks.
Telecommunications and information exchange between systems -
ISOIIEC 11574: 1994, Information technology -
Private Integrated Services Network - Circuit-mode 64 kbit/s bearer services - Service
description, functional capabilities and information fzows.
ISOIIEC 11579- 1: 1994, Information technology - Telecommunications and information exchange between systems -
Private integrated services network - Part 1: Reference configuration for PISN Exchanges
(PINX).
ISO/IEC 13863: 1995, Information technology - Telecommunications and information exchange between systems -
Private Integrated Services Network - Specification, functional model and information flows -
Path replacement additional network feature.
ISOIIEC 13864: 1995, Information technology - Telecommunications and information exchange between systems -
Private Integrated Services Network - Specification, functional model and information flows -
Name identification supplementary services.
ISO/IEC 13865:1995, Information technology - Telecommunications and information exchange between systems -
Private Integrated Services Network - Specification, functional model and information flows -
Call transfer supplementary service.
Information technology -
ISO/IEC 13866: 1995, Telecommunications and information exchange between systems -
Private Integrated Services Network -
Specification, functional model and information flows -
Call completion supplementary services.
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OISOLIEC
ISO/IEC 148451996 (E)
Telecommunications and information exchange between systems
ISO/IEC 13872: 1995, Information technology -
Specification, functional model and information flows -
Private Integrated Services Network -
Call diversion supplementary services.
Telecommunications and information exchange between systems -
ISO/IEC 14136:1995, Information technology -
Specification, functional models and information flows -
Private Integrated Services Network -
Identification supplementary services.
ISOIIEC 14841:1996, Information technology - Telecommunications and information exchange between systems -
Private Integrated Services Network - Specification, functional model and information flows -
Call offer supplementary service.
Telecommunications and information exchange between systems -
ISO/IEC 14842: 1996, Information technology -
Private Integrated Services Network - Specification, functional model and information flows - Do
not disturb and do not disturb override supplementary services.
Vocabulary of terms for ISDNs (Blue Book).
CCITT Rec. I. 112: 1988,
CCITT Rec. I. 130: 1988, Method for the characterization of telecommunication services supported by an ISDN and
network capabilities of an ISDN (Blue Book).
Principles of telecommunication services supported by an ISDN and the means to describe them
CCITI’ Rec. 1.210: 1988,
(Blue Book).
CCITI’ Rec. 1.221:1988, Common specific characteristics of services, Definition of par. 3 “busy” in an ISDN (Blue Book).
CCITI Rec. 2.100: 1988, Specification and Description Language (Blue Book).
4 Definitions
For the purposes of this International Standard, the following definitions apply.
41 . External definitions
This International Standard uses the following terms defined in other documents:
-
(CCITT Rec. 1.210)
Basic service
(ISO/IEC 13864)
Calling Party Name
-
(CCITT Rec. I. 112)
Connection
-
Integrated Services Digital Network (CCITT Rec. I. 112)
-
(ISOLIEC 13864)
Name
-
(CCITT Rec. 1.221)
Network Determined User Busy
-
Number (ISOLIEC 11571)
-
(ISOLIEC 11579- 1)
Private Integrated Services Network (PISN)
-
(ISOLIEC 11579- 1)
Private Integrated Services Network Exchange (PINX)
-
Service (CCITT Rec. I. 112)
-
(CCITT Rec. I. 112)
Signalling
-
(ISO/IEC 1157 1)
Subaddress
-
Supplementary Service (CCITT Rec. 1.210)
-
(ISOLIEC 11574)
User
-
(CCITI’ Rec. 1.221)
User Determined User Busy
This International Standard refers to the following basic call functional entity (FEs) defined in ISO/IEC 11574:
- Call Control (CC)
- Call Control Agent (CCA)
2
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OISOIIEC ISO/IEC 14845: 1996 (E)
This International Standard refers to the following basic call inter-FE relationships defined in ISO/IEC 11574:
-
rl
-
r2
-
r3
This International Standard refers to the following basic call information flows defined in ISO/IEC 11574:
- Disconnect request/indication
- Release request/indication
-
Release response/confirmation
- Setup request/indication
- Setup response/confirmation.
ISO/IEC 11574:
This International Standard refers to the following basic call information flow service elements defined in
-
Destination Number
- Connection type.
This International Standard refers to the following information flow elements defined in ISO/IEC 14136:
- Originating number
- Originating subaddress.
4.2 Other definitions
busy : A property of a user for whom either a Network Determined User Busy or User Determined User Busy condition exists.
conference type connection : A connection between the served user, user B and user C, where all users have user information
connection with each other.
consultation : Invocation of SS-CI after the calling user has been informed that a call has failed because of busy at the
destination.
consultation timer : A timer governing the time in which the calling user is allowed to request invocation of SS-CI after being
informed that a call has failed because of busy at the destination. The duration of the timer is an implementation option.
established call : The active call that is selected for intruding on.
forced release : The release of the established call on request from the served user during the intrusion state.
immediate invocation : Invocation of SS-CI as part of the initial call set up.
impending intrusion state : The condition of an established call and an intruding call after provision of an impending intrusion
warning notification and before establishment of communication between the served user and user B.
notification : A notification provided before communication established between the served
impending intrusion
user and user B.
implementation option : An option for the implementor of the service to include or not to include in the service providing
system.
intruding call : A call in which the served user requests SS-CI.
the served user and user B
intrusion state : The condition of an established call after establi shment of communication between
and prior to termination of SS-CI or invocation of wait on busy.
intruding call connected notification : A notification provided on establishment of communication between the served user
and user B.
isolation : The breaking of the user information connection to and from user C during the intrusion state.
the destination CC so that a
path retention : The retaining of the network connection between the originating CC and
supplementary service (such as SS-CI) can be invoked without establishing a new connection.
3
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OISOIIEC
ISO/IEC 14845: 1996 (E)
served user The user who requests SS-CI.
time to intrusion : The duration of the impending intrusion state.
user B : The wanted user that is subject to the call intrusion.
user C : The other user in the established call.
wait on busy state : A state that can be entered from the intrusion state and in which the intruding call is disconnected from
user B and is waiting for user B to answer the call.
5 List of acronyms
ANF Additional Network Feature
cc Call Control (functional entity)
CCA Call Control Agent (functional entity)
Call Completion to Busy Subscriber
CCBS
CCNR Call Completion No Reply
CD Call Deflection
CFB Call Forwarding Busy
CFNR Call Forwarding No Reply
Call Forwarding Unconditional
CFU
CI Call Intrusion
CICL Call Intrusion Capability Level
CIPL Call Intrusion Protection Level
Calling Line Identification Presentation
CLIP
CLIR Calling/Connected Line Identification Restriction
CNIP Calling Name Identification Presentation
CNIR Calling/Connected Name Identification Restriction
co Call Offer
Connected Line Identification Presentation
COLP
CONP Connected Name Identification Presentation
CT Call Transfer
DND Do Not Disturb
DNDO Do Not Disturb Override
Functional Entity
FE
Integrated Services Digital Network
ISDN
NDUB Network Determined User Busy
PINX Private Integrated Services Network Exchange
PISN Private Integrated Services Network
SDL Specification and Description Language
Supplementary Service
ss
TE Terminal Equipment
UDUB User Determined User Busy
WOB Wait On Busy
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OISOIIEC
ISO/IEC 14845: 1996 (E)
6 SS-CI stage 1 specification
6.1 Description
6.1.1 General description
Call Intrusion (SS-CI) is a supplementary service which, on request from the served user, enables the served user to establish
communication with a busy called user (user B) by breaking into an established call between user B and a third user (user C).
On successful intrusion, user C is either connected in a conference type connection with the served user and user B or
disconnected from user B (isolated).
An intrusion request is only accepted if the served user has a higher Call Intrusion Capability Level (CICL) than the Call
Intrusion Protection Level (CIPL) of both user B and user C.
There are three implementation options that provide the served user with additional capabilities following successful intrusion:
0
Forced release, allowing the served user to release the established call;
a Isolation, allowing the served user, if a conference type connection has been established, to isolate user C;
0
Wait on busy, allowing the served user to cause a transition from the intrusion state to the wait on busy state.
6.1.2 Qualifications on applicability to telecommunication services
SS-CI is applicable to all basic services defined in ISO/IEC 11574.
6.2 Procedures
6.2.1 Provision/withdrawal
SS-CI shall be provided or withdrawn after prearrangement with the service provider.
SS-CI shall be provided on a per PISN number basis. For each PISN number, the supplementary service may be provided for
those basic services for which it is considered meaningful (see 6.1.2) provided at that PISN number or for only some of these
basic services provided at that PISN number.
A Call Intrusion Capability Level (CICL) shall be allocated to the served user. Call Intrusion Protection Levels (CIPLs) shall be
allocated to potential individual users B and C within the PISN and to gateways to other networks (for use on behalf of users
outside the PISN). The procedure by which CICL and CIPL are allocated is outside the scope of this International Standard.
CICL shall have a value in the range 1 (lowest capability) to 3 (highest capability). At least one of the CICL values shall be
offered.
CIPL shall have a value in the range 0 (no protection) to 3 (total protection). CIPL values 0 and 3 shall be offered, and values 1
and 2 may, as an implementation option, be offered.
Note - It is not precluded that CIPL values can be variable, e.g. a user may have the possibility to change the CIPL value with a user procedure. CIPL values
assigned to gateways may also be variable, e.g. depending on whether the gateway is used for an incoming or outgoing call to the PISN. The details of such
capabilities are outside the scope of this International Standard.
At least one of the methods of invoking SS-CI (see 6.2.2.2.1) shall be supported. If both methods given in 6.2.2.2.1 are
supported, then a user may be provided with one or both methods.
A number of implementation options concern features available to the served user during call intrusion. The served user may, at
time of provision of SS-CI, be given the choice of being provided with some, all or none of these or the options may be
generally available. These implementation options are: forced release, isolation, and wait on busy.
When these options are selectable on a per served user basis, they may be selectable separately for each basic service for which
SS-CI is provided, or selectable only for all basic services for which SS-CI is provided.
6.2.2 Normal procedures
6.2.2.1 Activation/deactivation/registration/interrogation
SS-CI shall be activated by the service provider upon provision, and deactivated upon withdrawal.
Registration and interrogation shall not apply.
c
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ISO/IEC 14845: 1996 (E) OISO/IEC
6.2.2.2 Invocation and operation
6.2.2.2.1 Methods of invoking SS-CI
There are two different ways to invoke SS-CI. A PISN shall offer one or both of these ways. These ways are:
shall be able,
Consultation: the served user, on being informed that a call has failed because of busy at the destination,
0
within a defined period (consultati .on timer), to request SS-CI.
ii) Immediate invocation: the served user shall be able to request SS-CI as part of the initial call set up.
6.2.2.2.2 Verification and selection of compatible call
If the consultation method is provided to the served user, the following procedure shall apply. If a call fails due to busy at the
called user B and the PISN is not aware that intrusion is not allowed (e.g. because of insufficient CICL), the PISN shall notify
the served user that the call has failed because of busy at the called user B and that intrusion may be possible. The served user
may then request SS-CI.
If the immediate invocation method is provided to the served user, the served user may request SS-CI with the initial call set up.
For both invocation alternatives the following shall apply. Upon receiving an intrusion invocation request from the served user,
the PISN shall check that the user B’s number used by the served user, when requesting the service, is also a number involved in
a compatible call in the active state. A called user’s subaddress supplied by the served user shall not be taken into account when
selecting a call to intrude on. Further, the PISN checks that the CIPL values of the users in the active call are lower than the
CICL value of the served user. If user B’s CIPL value is lower than the CICL value and user B has several compatible calls in
the active state, the CIPL values of the other users in the calls shall be checked, in any order, until a CIPL value lower than the
CICL value is found. A call that passes these checks shall be selected as the established call.
When the established call has been selected, the users in the established call may as an option be provided with an Impending
intrusion warning notification and a short delay (not exceeding 10s) before the connection between the served user and user B
is formed. If this notification is provided, it shall be sent to both users in the established call and optionally to the served user
and the impending intrusion state shall be entered.
notificati on can be accompanied by an in-band tone or announcement to user B and user C. An
Note - The Impending intrusion warning
announcement can be given to the served user.
If no Impending intrusion warning notification is provided, the procedures of 6.2.2.2.4 for setting up the connection between
the served user and user B shall apply immediately.
6.2.2.2.3 Actions during impending intrusion state
6.2.2.2.3.1 Impending intrusion state ends
A time period, time to intrusion (l-10 seconds, implementation option), after the Impending intrusion warning notification has
been provided the impending intrusion state shall be terminated and the procedures of 6.2.2.2.4 for setting up the connection
between the served user and user B shall apply.
6.2.2.2.3.2 Release of intruding call
If the served user releases the intruding call during the impending intrusion state, user B and user C shall each be notified that
intrusion has terminated. SS-CI shall be terminated.
6.2.2.2.3.3 Release of established call
If user B or user C releases the established call, the served user shall be notified that intrusion is no longer applicable. SS-CI
shall be terminated and the network shall attempt to present the call from the served user to user B and continue in accordance
with basic call procedure.
6.2.2.2.4 Setting up the connection between served user, user B and user C
There are two different ways (implementation options) for the served user to be connected to user B. Either the network shall
form a conference type connection between user B, user C and the served user, or the network shall isolate user C and connect
the served user only to user B. In either case, when the connection has been established, the intrusion state shall be entered.
If the first option is implemented, the users in the established call shall be provided with an Intruding call connected
notification when the served user is connected. The served user shall receive confirmation that the intrusion request has been
accepted and that a conference type connection has been formed.
Note - The three users can also receive a superimposed in-band indication (e.g. a repeated tone) while the conference type connection exists.
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OISO/IEC ISO/IEC 14845: 1996 (E)
If the latter option is implemented, user C shall be given a notification that isolation has occurred and user B shall be informed
that user C has been isolated and that an intrusion has occurred. The served user shall receive confirmation that the intrusion
request has been accepted and that isolation has occurred. The served user and user B shall be connected and no conference
type connection shall be formed. The established call shall remain in progress but with the user information connection to user
C broken.
Note - User C can also receive an in-band tone or announcement while isolated.
Note - The option selected can depend on the particular basic service being used.
6.2.2.2.5 Actions during intrusion state
6.2.2.2.5.1 Release of intruding call
If the served user releases the intruding call, the established call shall revert to the state that existed before the intrusion state,
and the intrusion state shall be terminated. User B and user C shal 1 be notified that the intrusion state has been terminated.
If user B releases the intruding call, the established call shall revert to the state that existed before the intrusion state, and the
intrusion state shall be terminated. U ser C shall be notified that the intrusion state has terminated.
6.2.2.2.5.2 Release of the established call
If user B or user C releases the established call, the served user shall be notified that call intrusion has terminated. If user C
releases the established call, user B shall be notified that intrusion has terminated. The intruding call shall become an ordinary
call between user B and the served user.
6.2.2.2.5.3 Forced release
As an implementation option the served user may, during the intrusion state, request a forced release of user C. User C may be
isolated or in a conference type connection when the request is made. A successful forced release shall be notified to the served
user, to user B and to user C. The intruding call shall continue as an ordinary call between the served user and user B, the
established call shall be released, and the intrusion state shall be terminated.
6.2.2.2.5.4 Isolation on request from served user
If a conference type connection is used, user C may (implementation option) be isolated from the conference type connection
on request from the served user. If the request is accepted the served user shall receive confirmation and the established call
shall be disconnected from user B, but not released. The served user shall be connected only to user B. The intrusion state shall
continue and the ensuing situation shall be identical to the situation where isolation occurred when the intrusion state was
entered. User C and user B shall be notified that user C has been isolated.
6.2.2.2.5.5 Transition from intrusion state to wait on busy state
As an implementation option it may be possible for the served user to request transition from the intrusion state to the wait on
busy state. On acceptance of such a request, the served user shall receive a confirmation, the established call shall revert back to
the state that existed before intrusion, user B shall be reconnected to user C if isolated, the intruding call shall be disconnected
from user B and the intrusion state shall be terminated. The intruding call shall not be released but shall enter the wait on busy
state. User B shall be notified that the intrusion has terminated and wait on busy has been invoked. User C shall be notified that
the intrusion has terminated.
6.2.2.2.6 Actions during wait on busy state
6.2.2.2.6.1 Served user releases
If the served user releases during the wait on busy state, user B shall be notified and SS-CI terminated.
6.2.2.2.6.2 User B answers the waiting call
If user B answers the waiting call, SS-CI shall be terminated, and the served user shall be notified and connected to user B. The
call shall become an ordinary call between user B and the served user.
6.2.2.2.6.3 Re-intrusion request
When the network receives a request for re-intrusion, the network shall verify the request and select an established call in
accordance with 6.2.2.2.2 and set up the connection in accordance with 6.2.2.2.3 (if applicable) and 6.2.2.2.4.
6.2.
...
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