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\s12PART\ II
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.RT
.ce 0
.sp 1P
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\fBI.200\(hySeries Recommendations\fR \v'2P'
.EF '%	 \ \ \ ^''
.OF ''' \ \ \ ^	%'
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\fR \fBSERVICE\ CAPABILITIES\fR 
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.LP
\fBMONTAGE: PAGE 102 = PAGE BLANCHE\fR 
.sp 1P
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.LP
.bp
.sp 2P
.LP
\fBRecommendation\ I.200\fR 
.RT
.sp 2P
.sp 1P
.ce 1000
\fBGUIDANCE\ TO\ THE\ I.200\(hySERIES\ OF\ RECOMMENDATIONS\fR 
.EF '%	Fascicle\ III.7\ \(em\ Rec.\ I.200''
.OF '''Fascicle\ III.7\ \(em\ Rec.\ I.200	%'
.ce 0
.sp 1P
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\fI(Melbourne, 1988)\fR 
.sp 9p
.RT
.ce 0
.sp 1P
.LP
\fB1\fR 	\fBGeneral\fR 
.sp 1P
.RT
.PP
The Recommendations in the I.200\(hySeries cover the aspects of the
telecommunications services supported by ISDNs. They contain the definitions, 
descriptions and details on the provision of bearer services, teleservices 
and their associated supplementary services. 
.PP
In the layout of the I.200\(hySeries of Recommendations the following
objectives have been taken into account:
.RT
.LP
	\(em
	to achieve a systematic structure which is open to future
enhancement;
.LP
	\(em
	to facilitate the requirements of different readers by
separating, in specific Recommendations, general service concepts and
definitions from Recommendations covering detailed characteristics of
individual services;
.LP
	\(em
	to use systematically the service description method given
in Recommendation\ I.130 where, the stage\ 1, telecommunication services are
described in three steps:
.LP
	1)
	prose definition and description;
.LP
	2)
	static description using attributes;
.LP
	3)
	dynamic description using graphic means.
.sp 2P
.LP
\fB2\fR 	\fBStructure of the I.200\(hySeries of Recommendations\fR 
.sp 1P
.RT
.PP
Section\ 2.1 gives the layout and Figure\ 1/I.200 illustrates the
structure of the I.200\(hySeries of Recommendations.
.PP
The general service concepts and principles are given in
Recommendation\ I.210. Annexes to Recommendation\ I.210 describe the application 
of the service description method to the three service families: bearer 
services, teleservices and supplementary services.
.PP
A separate section of the I.200\(hySeries is allocated to each service
family. Within each of these sections the first Recommendation gives an
overview of the services within each family and the subsequent Recommendations 
specify in detail individual services. The reader interested in an overview 
of service concepts and principles, as well as the method to describe services, 
will find them in Recommendations\ I.210, I.230, I.240 and\ I.250.
.PP
The reader interested in the detailed characteristics of individual
services will find them in Recommendations\ I.231, I.232, I.241 and\ I.251\(hyI.257. 
Detailed items of common significance are defined and described in 
the\ I.220\(hySeries of Recommendations.
.PP
\fINote\fR \ \(em\ In the CCITT Red Book\ (1984) all ISDN service requirements
were contained in three Recommendations, numbered\ I.210, I.211 and\ I.212.
References have been made widely to these three Recommendations in other
Recommendations and elsewhere, and to facilitate a translation to the new
CCITT Blue Book\ (1988) version of the I.200\ Recommendations Appendix\ I shows
the mapping between the Red Book and Blue Book versions of the I.200\(hySeries 
of Recommendations. 
.RT
.sp 2P
.LP
2.1
	\fILayout of the I.200\(hySeries of Recommendations\fR 
.sp 1P
.RT
.sp 1P
.LP
I.200
	Guidance to the I.200\(hySeries of Recommendations
.sp 9p
.RT
.sp 2P
.LP
SECTION\ 1\ \(em
	\fIGeneral aspects of services in an ISDN\fR 
.sp 1P
.RT
.sp 1P
.LP
I.210
	Principles of telecommunication services supported by an ISDN and the
means to describe them
.sp 9p
.RT
.sp 2P
.LP
SECTION\ 2\ \(em
	\fICommon aspects of services in an ISDN\fR 
.sp 1P
.RT
.sp 1P
.LP
I.220
	Common dynamic description of basic telecommunication services
.sp 9p
.RT
.LP
I.221
	Common specific characteristics of services
.bp
.sp 2P
.LP
SECTION\ 3\ \(em
	\fIBearer services supported by an ISDN\fR 
.sp 1P
.RT
.sp 1P
.LP
I.230
	Definition of bearer services categories
.sp 9p
.RT
.LP
I.231
	Circuit mode bearer services categories
.LP
I.232
	Packet mode bearer services categories
.sp 2P
.LP
SECTION\ 4\ \(em
	\fITeleservices supported by an ISDN\fR 
.sp 1P
.RT
.sp 1P
.LP
I.240
	Definition of teleservices
.sp 9p
.RT
.LP
I.241
	Teleservices supported by an ISDN
.sp 2P
.LP
SECTION\ 5\ \(em
	\fISupplementary services in an ISDN\fR 
.sp 1P
.RT
.sp 1P
.LP
I.250
	Definition of supplementary services
.sp 9p
.RT
.LP
I.251
	Number identification supplementary services
.LP
I.252
	Call offering supplementary services
.LP
I.253
	Call completion supplementary services
.LP
I.254
	Multi\(hyparty supplementary services
.LP
I.255
	\*QCommunity of Interest\*U supplementary services
.LP
I.256
	Charging supplementary services
.LP
I.257
	Additional information transfer supplementary services
.LP
.rs
.sp 29P
.ad r
\fBFigure 1/I.200, p.\fR 
.sp 1P
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APPENDIX\ I
.ce 0
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(to Recommendation I.200)
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\fBMapping between the Red Book and Blue Book\fR 
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.sp 1
\fIRed Book Recommendations\fR \fIBlue Book Recommendations\fR Rec.
	I.210\ \(sc
	1\(hy6
	Rec.
	I.210\ \(sc
	1\(hy6
	
Rec.
	I.211\ \(sc
	1
	2
	2.1
	2.1.1
	2.1.2
	2.1.3
	2.1.4
	2.1.5
.LP
	2.1.6
	2.1.7
	2.1.8
	2.2
	2.2.1
	2.2.2
	3
	3.1.1
	3.1.2
	3.1.3
	3.1.4
	3.1.5
	3.1.6
	3.1.7
	3.1.8
	3.2.1
	3.2.2
	
.LP
Rec.
	I.210\ Annex B 
	I.230\ \(sc
	2
	2.1
	I.231\ \(sc
	1
	2
	3
	4
	Deleted
	I.231\ \(sc
	6
	7
	8
	I.230\ \(sc
	2.2
	I.232\ \(sc
	1
	2
	I.230\ \(sc
	3
	I.231\ \(sc
	1.7.2
	2.7.2
	3.7.2
	4.7.2
	Deleted
.LP
	I.231\ \(sc
	6.7.2
	7.7.2
	8.7.2
	I.232\ \(sc
	1
	2
	Rec.
	I.212\ \(sc
	1
	2
	Rec.
	I.210\ \(sc
	C.1
	C.2
	
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SECTION\ 1
.ce 0
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\fBGENERAL\ ASPECTS\ OF\ SERVICES\ IN\ ISDN\fR 
.ce 0
.sp 1P
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\fBRecommendation\ I.210\fR 
.RT
.sp 2P
.ce 1000
\fBPRINCIPLES\ OF\ TELECOMMUNICATION\ SERVICES\ SUPPORTED\ BY\ AN\fR  |
\fBISDN\fR 
.EF '%	Fascicle\ III.7\ \(em\ Rec.\ I.210''
.OF '''Fascicle\ III.7\ \(em\ Rec.\ I.210	%'
.ce 0
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\fBAND\ THE\ MEANS\ TO\ DESCRIBE\ THEM\fR 
.ce 0
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\fI(Malaga\(hyTorremolinos, 1984; amended at Melbourne, 1988)\fR 
.sp 9p
.RT
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.LP
\fB1\fR 	\fBGeneral\fR 
.sp 1P
.RT
.PP
An ISDN will support a wide range of services as described
generally in Recommendation I.120. The purpose of this Recommendation is to
provide a classification of such services, the means for the description of
such services based on the description method as defined in
Recommendation\ I.130, and to give a basis for the definition of the network
capabilities required by an ISDN. These network capabilities are defined 
in the I.300\(hySeries of Recommendations. 
.PP
Using the service concepts and the means for the description of
services as given in this Recommendation, recommended bearer services are
defined and described in the I.230\(hySeries of Recommendations, recommended
teleservices are defined and described in the I.240\(hySeries of Recommendations 
and recommended supplementary services are defined and described in the 
I.250\(hySeries of Recommendations.
.RT
.sp 2P
.LP
\fB2\fR 	\fBService concepts\fR 
.sp 1P
.RT
.PP
2.1
Services supported by an ISDN are the communication capabilities
made available to customers by telecommunication service providers. An ISDN
will provide a set of network capabilities which are defined by standardized
protocols and functions and enable telecommunication services to be offered 
to customers. 
.sp 9p
.RT
.PP
A service provision by a telecommunication service provider to a
customer connected to an ISDN may cover the whole or only part of the means
required to fully support the service. The operational and commercial features 
associated with provision of the service are included in the service concept. 
.PP
The service classification and descriptions which follow are
independent of different possible arrangements for ownership and provision 
to the customer of the means required to support a service. The customer 
may 
therefore be offered, by the Administration, services or service
support.
.RT
.PP
2.2
The method used for the characterization of telecommunication
services is described in Recommendation I.130 \*QMethod for the characterization 
of telecommunication services supported by an ISDN and network capabilities 
of an ISDN\*U. Within this method the first stage is an overall service 
description from the user's point of view. In stage 1 there are three steps: 
.LP
	Step\ 1.1
	Prose service definition and description
.LP
	Step\ 1.2
	Static description of the service using attributes
.LP
	Step\ 1.3
	Dynamic description of the service using graphic
means
.PP
Together these three steps define the service characteristics as
they apply at a given reference point where the customer accesses the
service.
.bp
.PP
Annexes A to D of this Recommendation give the format of stage 1
service descriptions as follows:
.RT
.LP
	Annex\ A:
	Structure for prose service definition and description
.LP
	Annex\ B:
	List of attributes and their possible values for
describing bearer services
.LP
	Annex\ C:
	List of attributes and their possible values for
describing teleservices
.LP
	Annex\ D:
	Dynamic description of the service using graphic
means
.PP
\fINote\ 1\fR \ \(em\ Recommendation I.140 describes the use of attributes 
for this purpose. 
.PP
\fINote\ 2\fR \ \(em\ The use of attributes for describing supplementary 
services is for further study. 
.PP
This format allows the information contained within stage 1 to be
structured in a consistent, comprehensive and logical manner. Only one 
overall format is recommended but it is recognized that certain sections 
of this format are only applicable to certain types of services. 
.RT
.PP
2.3
Telecommunication services are classified using their static
characteristics described by attributes. Therefore this Recommendation 
(except Annexes A and D) deals mainly with step 1.2 of the description 
method. 
.PP
A 
telecommunication service
is, from the static point of
view, composed of:
.LP
	\(em
	technical attributes as seen by the customer; and
.LP
	\(em
	other attributes associated with the service provision, e.g.
operational and commercial attributes.
.PP
Realization of the technical attributes of a telecommunication
service requires a combination of network and terminal capabilities and 
other service providing systems. 
.PP
2.4
Telecommunication services are divided in two broad families,
i.e.
.LP
	\(em
	bearer services
, and
.LP
	\(em
	teleservices
.
.PP
A 
supplementary service
modifies or supplements a 
basic  telecommunication service
. Consequently, it cannot be offered to a customer
.PP
as a stand alone service. It must be offered together with or in association
with a basic telecommunication service. The same supplementary service 
may be common to a number of telecommunication services. 
.PP
\fINote\fR \ \(em\ The concept of supplementary services corresponds to the
concept of optional user facilities in the X\(hySeries of Recommendations.
.PP
The concepts introduced here are illustrated in Table\ 1/I.210 and
are defined in more detail in\ \(sc\ 5.
.RT
.ce
\fBH.T. [T1.210]\fR 
.ce
TABLE\ 1/I.210
.ce
\fBClassification of telecommunication services\fR 
.T&
lw(48p) | lw(66p) | lw(48p) | lw(66p) .
			
.TE
.nr PS 9
.RT
.ad r
\fBTable [T1.210], p.\fR 
.sp 1P
.RT
.ad b
.RT
.sp 2P
.LP
\fB3\fR 	\fBCustomer access to telecommunication services supported\fR 
\fBby an ISDN\fR 
.sp 1P
.RT
.PP
3.1
Considering the reference configurations defined in
Recommendation\ I.411, customers can access various telecommunication services 
at different access points. Figure 1B/FI.210 shows these access points. 
.sp 9p
.RT
.PP
This figure takes into account that the network provider may offer to a 
customer connected to an ISDN the whole or only part of the means to fully 
support the service. 
.bp
.LP
.rs
.sp 16P
.ad r
\fBFigure 1/I.210, p.\fR 
.sp 1P
.RT
.ad b
.RT
.PP
3.2
The definitions of the access points introduced in Figure\ 1/I.210
are as follows:
.LP
	i)
	access points 1 (reference point T) and 2 (reference
point\ S)
are the access points for bearer services supported by an ISDN.
The choice between access point\ 1 (T) and\ 2 (S) depends on the ownership and
form of provision (to the customer) of the communications equipment at the
customer premises. The service classification and descriptions in the following 
are independent of different possible arrangements for such provision; 
.LP
	ii)
	at 
access point 4
(reference point R), depending on   the type of 
terminal adaptors
provided, other CCITT standardized
services may be accessed, e.g.\ according to the X\(hy and V\(hySeries of
Recommendations;
.LP
	iii)
	at 
access points 3 and 5
(user\(hyto\(hyterminal
interface), 
teleservices
are accessed \(em the teleservice concept
includes the terminal capabilities.
.PP
3.3
The following customer entities may be connected at access\fR 
points 1 and 2:
.LP
	\(em
	customer terminals;
.LP
	\(em
	customer systems, e.g. PABXs, LANs, service vendor systems;
.LP
	\(em
	private networks.
.PP
\fINote\fR \ \(em\ Customer terminals and systems may be private or provided 
by Administrations. 
.PP
All customer equipment connected to an ISDN interface at one of these
access points should meet the specifications of the protocols at that interface 
for all the layers that are included in the definition of the telecommunication 
service used. 
.PP
For some telecommunication services the service definition also covers 
some terminal functions and characteristics in addition to those specified 
by the protocols at the interface. This relates in particular to teleservices, 
and also to supplementary services (see Recommendation I.250). 
.RT
.PP
3.4
From the user's point of view the telecommunication services as
defined in the I.200\(hySeries of Recommendations will be used for some
applications.\fR For example, the telephony teleservice will be typically 
used for a 
human conversation (application). Likewise bearer services will be used for
applications. The area of applications is outside the scope of the I\(hySeries 
of Recommendations. The user's application of services is the responsibility 
of 
the user and not of the network. The network can have no knowledge of what
application is being used at any given time.
.PP
3.5
The telecommunication service, as described in this
Recommendation, is time\(hyindependent, that is to say that the description is
valid for all the time the service is available. Whenever a demand or
reserved service is invoked by a user, then the particular instance of the
service is referred to as a \fIcall\fR . Similarly, the instance also applies 
to 
the application as described in \(sc\ 3.4. The instance of an application is
referred to as a \fIcommunication\fR .
.bp
.sp 2P
.LP
\fB4\fR 	\fBCapabilities to support a telecommunication service\fR 
.sp 1P
.RT
.PP
4.1
The capabilities required to fully support a telecommunication service 
for a customer connected to an ISDN include: 
.sp 9p
.RT
.LP
	\(em
	network capabilities;
.LP
	\(em
	terminal capabilities, when required;
.LP
	\(em
	other services providing capabilities, when required;
.LP
	\(em
	operational and commercial features associated with the
service provision (i.e. sales or marketing aspects).
.PP
4.2
Network capabilities are described in detail in
Recommendation\ I.310.  Two different levels of ISDN network capabilities are
introduced in that Recommendation:
.LP
	\(em
	low layer capabilities which relate to bearer services;
.LP
	\(em
	high layer capabilities which together with low layer
capabilities relate to teleservices.
.PP
The low layer capabilities are defined as a set of Low Layer
Functions\ (LLF) (relating to layers 1\(hy3 in Recommendation X.200) which 
provide the capability for the carriage of user information over an ISDN 
connection.\fR These functions include: 
.LP
	\(em
	Basic Low Layer Functions (BLLF) supporting the necessary
layer\ 1\(hy3 requirements;
.LP
	\(em
	 Additional Low Layer Functions (ALLF) supporting, in addition to BLLFs, 
lower layer requirements of supplementary services. 
.PP
High layer capabilities are defined as a set of High Layer
Functions\ (HLF) generally associated with layers 4\(hy7 in Recommendation
X.200.
.PP
High Layer Functions are sub\(hydivided into Basic High Layer
Functions\ (BHLF) and Additional High Layer Functions (AHLF).
.PP
\fINote\fR \ \(em\ Depending on national regulations, ALLF, BHLF, and AHLF may
be provided by Administrations, or other suppliers.
.RT
.PP
4.3
The concept of describing network capabilities in terms of low
layer capabilities and high layer capabilities can equally be applied to
describe terminal capabilities. In the description of teleservices the 
HLF and LLF are included in the service definition. In the case of bearer 
service 
definition the terminal capabilities are not included but the terminal must
conform to the LLF of the bearer service.
.PP
\fINote\fR \ \(em\ The relationships between service categories,
network/terminal capabilities and functions are illustrated in Table 2/I.210.
.ce
\fBH.T. [T2.210]\fR 
.ce
TABLE\ 2/I.210
.ce
\fBRelationship between service categories,\fR 
.ce
\fBnetwork/terminal capabilities and functions\fR 
.T&
lw(36p) | lw(21p) | lw(21p) | lw(21p) | lw(15p) | lw(21p) | lw(21p) | lw(21p) 
| lw(15p) | lw(36p) . 
									
.TE
.nr PS 9
.RT
.ad r
\fBTable [T2.210], p.\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.PP
4.4
The operational service capabilities associated with a service
offering may include capabilities for maintenance, charging, user control of
service features, etc.
.PP
The use of such capabilities may involve terminal\(hynetwork
communication and may therefore be viewed as specific applications.
.PP
A more precise description of these capabilities and the
relationship to Recommendation X.200 needs further study.
.RT
.sp 2P
.LP
\fB5\fR 	\fBTelecommunication service classification\fR 
.sp 1P
.RT
.PP
5.1
The static characteristics of a telecommunication service
supported by an ISDN are described by service attributes. They are given in
Annexes\ B and\ C.
.sp 9p
.RT
.PP
There are two groups of service attributes applicable to user
information flow:
.LP
	\(em
	low layer attributes;
.LP
	\(em
	high layer attributes.
.PP
Bearer services are defined as including only low layer attributes. Teleservices 
are defined as including both low layer attributes and high layer attributes. 
.PP
The relationship between telecommunication service attributes and
low/high layer functions is illustrated in Figure\ 2/I.210.
.RT
.LP
.rs
.sp 32P
.ad r
\fBFigure 2/I.210, p.\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.sp 2P
.LP
5.2
	\fIBearer services supported by an ISDN\fR 
.sp 1P
.RT
.PP
5.2.1
Bearer services supported by an ISDN provide the capability for information 
transfer between ISDN access points 1 or 2 and involve only low 
layer functions.
.sp 9p
.RT
.PP
The customer may choose any set of high layer (at least 4\(hy7)
protocols for his communication, and the ISDN does not ascertain compatibility 
at these layers between customers. An example of a bearer service is a 
demand circuit\(hymode, 64\ kbitB/Fs unrestricted, 8\ kHz structured bearer 
service. 
.PP
5.2.2
Bearer services are characterized from a static point of view
by a set of low layer attributes given in Annex\ B. These
attributes are classified into three categories:
.LP
	\(em
	information transfer attributes
;
.LP
	\(em
	access attributes
; and
.LP
	\(em
	general attributes
, including 
operational and
commercial attributes
.
.PP
The bearer capability defines the technical features of a bearer
service as they appear to the user at the appropriate access point (1 or 2).
.PP
The bearer capability is characterized by information transfer and
access attributes. A bearer capability is associated with every bearer
service.
.PP
\fINote\fR \ \(em\ It is likely that some Quality of Service parameters 
\(em such as error rate or call set\(hyup delay \(em should be extracted 
in order to form a new 
attribute allocated to the information transfer category. Identification 
and definition of such parameters require further consideration. 
.PP
Individual bearer services categories are defined and described in
the I.230\(hySeries of Recommendations.
.RT
.PP
5.2.3
A bearer service provides the user with the possibility of
gaining access to various forms of communication, covering for example:
.LP
	\(em
	information transfer between users employing the same
access points (1 or 2) and access attributes (see\ Figure\ 3\fIa\fR /I.210);
.LP
	\(em
	 information transfer between users employing different access attributes 
at the access points (1 or 2) involved 
(see\ Figure\ 3\fIb\fR /I.210); and
.LP
	\(em
	information transfer between a user and a separate resource
providing high layer functions (see\ Figure\ 3\fIc\fR /I.210).
.sp 2P
.LP
5.3
	\fITeleservices supported by an ISDN\fR 
.sp 1P
.RT
.PP
5.3.1
Teleservices provide the full capacity for communication by
means of terminal and network functions and possibly functions provided by
dedicated centres.
.sp 9p
.RT
.PP
A teleservice supported by an ISDN should use only one (or a small number 
of) bearer capability(ies) recommended by the CCITT. It should be noted 
that in the case where more than one of the recommended bearer capabilities 
is used for a given teleservice, network interworking functions may be 
required 
under the responsi
bility of the teleservice provider. However, a user
operating a specific application is not prevented from using a terminal
compatible with a given teleservice in association with a bearer capability 
not recommended for this teleservice. Examples of teleservices are telephony, 
Teletex and Videotex.
.PP
5.3.2
Teleservices are described from a static point of view by a set
of low layer and high layer attributes, and operational and commercial
attributes, as given in Annex C of this Recommendation.
.PP
Low layer attributes are those used to characterize the bearer
capability (see \(sc\ 5.2.2). High layer attributes are used in
Recommendation\ I.241 to describe message\(hyrelated (i.e.\ message on 
layer\ 7) 
characteristics of a service (basic high layer attributes) or of a
supplementary service (supplementary high layer attributes). They refer 
to the functions and protocols of layers\ 4\(hy7 in the Recommendation\ 
X.200 framework 
which are concerned with the transfer, storage and processing of user messages 
(provided by a subscriber's terminal, a retrieval centre, or a network 
service centre). 
.PP
Therefore, not all these attributes can be applied directly at the
user\(hyto\(hyterminal interface (access points 3 or 5) as they represent 
two kinds of features, the bearer capability and the terminal features, 
that are not 
directly perceived by the user.
.PP
The definition of appropriate attributes and the specifications of
teleservices at this access point from the user point of view (man\(hymachine
interface) is for further study and the subject of E\(hyand F\(hySeries
Recommendations.
.PP
Individual teleservices are defined and described in the
I.240\(hySeries of Recommendations.
.bp
.RT
.LP
.rs
.sp 36P
.ad r
\fBFigure 3/I.210, p.\fR 
.sp 1P
.RT
.ad b
.RT
.PP
5.3.3
A teleservice provides the user with the possibility of gaining
access to various forms of applications (or teleservice applications) covering, 
for example: 
.LP
	\(em
	 teleservice application involving two terminals providing the same teleservice 
attributes at both access points (3 or 5) \(em (see 
Figure\ 4\fIa\fR /I.210);
.LP
	\(em
	teleservice application involving a terminal at one access
point (3 or 5) and HLF functions located within the ISDN \(em (see
Figure\ 4\fIb\fR /I.210);
.LP
	\(em
	 teleservice application involving terminals based on different teleservice 
attributes at each access point \(em in this case, the use of HLF 
functions in the ISDN is necessary (interworking situation) \(em
(see\ Figure\ 4\fIc\fR /I.210);
.LP
	\(em
	 teleservice application involving a terminal at one access point (3 or 
5) and a system providing HLF functions (see Figure\ 4\fId\fR /I.210); 
.LP
	\(em
	teleservice application involving two terminals at both
access points (3 or 5) and an intervening system providing HLF functions 
(see Figure\ 4\fIe\fR /I.210). In this case, teleservice attributes can 
be different at 
each terminal access point.
.bp
.LP
.rs
.sp 41P
.ad r
\fBFigure 4/I.210, p.\fR 
.sp 1P
.RT
.ad b
.RT
.sp 1P
.LP
5.4
	\fISupplementary services supported by an ISDN\fR 
.sp 9p
.RT
.PP
Supplementary services supported by an ISDN provide additional
capabilities to be used with bearer services and teleservices. They cannot 
be offered to a customer as a stand alone service. 
.PP
Supplementary services are characterized by a prose definition and
description following the layout given in Annex A and a dynamic description
applying the means given in Annex D.
.PP
The use of the attribute technique for supplementary services is for
further study. The individual supplementary services are described in the\fR 
I.250\(hySeries of Recommendations.
.bp
.RT
.sp 2P
.LP
\fB6\fR 	\fBProvision of telecommunication services\fR 
.sp 1P
.RT
.PP
6.1
A telecommunication service is provided
by an Administration, andB/For other service providers. Customer terminals
and systems may be privately owned or provided by Administrations.
Depending on the nature of customer ownership within the customer premises 
(TE or TE and NT2), a telecommunication service is provided at different 
access 
points.
.sp 9p
.RT
.PP
6.2
The provision of telecommunication services implies:
.LP
	\(em
	subscription ensuring the basic service
and possibly
subscription to supplementary services;
.LP
	\(em
	registration into a service directory
in the case where demand services are used;
.LP
	\(em
	compatibility between terminals;
.LP
	\(em
	interworking capabilities
(this point needs further
study).
.PP
6.3
The provision of individual bearer services is given in the\fR 
I.230\(hySeries, the provision of individual teleservices is given in the
I.240\(hySeries and the association of supplementary services to bearer 
services and teleservices is given in Recommendation I.250. 
\v'1P'
.ce 1000
ANNEX\ A
.ce 0
.ce 1000
(to Recommendation I.210)
.sp 9p
.RT
.ce 0
.ce 1000
\fBStructure for\fR 
\fBprose service definition and\fR 
.sp 1P
.RT
.ce 0
.ce 1000
\fBdescription\fR \fB\ \(em\ Step 1.1 of description method (Recommendation 
I.130)\fR 
.ce 0
.LP
A.1
	\fIStructure of prose service definition and description\fR 
.sp 1P
.RT
.PP
Prose service definition and description is the first step (1.1) of the 
stage 1 overall service description from the user's point of view 
(Recommendation\ I.130). The prose definition of a telecommunication service
will be structured as follows:
.RT
.LP
	1
	\fIDefinition\fR 
.LP
	2
	\fIDescription\fR 
.LP
	2.1
	General description
.LP
	2.2
	Specific terminology
.LP
	2.3
	Qualifications
.LP
	3
	\fIProcedures\fR 
.LP
	3.1
	ProvisionB/Fwithdrawal
.LP
	3.2
	Normal procedures
.LP
	3.2.1
	ActivationB/FdeactivationB/Fregistration
.LP
	3.2.2
	Invocation and operation
.LP
	(3.2.3
	InterrogationB/Fediting)
.LP
	3.3
	Exceptional procedures
.LP
	3.3.1
	ActivationB/FdeactivationB/Fregistration
.LP
	3.3.2
	Invocation and operation
.LP
	(3.3.3
	InterrogationB/Fediting)
.LP
	3.4
	Alternative procedures
.LP
	3.4.1
	Activation/deactivation/registration
.LP
	3.4.2
	Invocation and operation
.LP
	(3.5
	Verification)
.LP
	4
	\fINetwork capabilities for charging\fR 
.LP
	5
	\fIInterworking requirements\fR 
.LP
	6
	\fIInteraction with other supplementary services\fR 
.PP
\fINote\ 1\fR \ \(em\ Where a particular section would not be appropriate 
for a particular service (basic or supplementary) \*Qnot applicable\*U 
appears in that 
section for that service. Some such items have been identified by paragraph
numbering in parenthesis.
.bp
.PP
\fINote\ 2\fR \ \(em\ Where information contained under one item (e.g. 
3.2.1) for a particular service is extensive, then this item may be further 
sub\(hydivided 
under sub\(hyheadings as necessary.
.PP
\fINote\ 3\fR \ \(em\ In a Recommendation containing prose definitions and
descriptions, an additional digit is prefixed to the above numbering structure 
to make the section numbering conform to the presentation rules laid out 
in 
Recommendation\ A.15.
.RT
.sp 2P
.LP
A.2
	\fIExplanation of the terms and content of the items in the\fR 
\fIservice prose definition and description\fR 
.sp 1P
.RT
.LP
	1
	\fIDefinition\fR 
.LP
	This section provides a short description of the service in
terms of the perceptions of the user receiving the service and any other 
users involved in the service. 
.LP
	2
	\fIDescription\fR 
.LP
	This section expands on the definition and summarizes the
operation of the service in a generic form which does not constrain terminal 
or network design. It is intended to allow an understanding of the service 
without regard to implementation. It also includes any specific terminology 
used within the prose definition and description, and any qualifications. 
For basic 
services this section details the applications which could utilize the 
service whilst for supplementary services this section details their applicability 
to particular telecommunication services. 
.LP
	3
	\fIProcedures\fR 
.LP
	 The overall operation of the service in its various states is described 
in this section 3. These procedures relate to all actions between the user(s) 
and the network during the period that the service is available. 
.LP
	3.1
	\fIProvision/withdrawal\fR 
.LP
	This section describes the means by which the service is made
available by the service provider, e.g.\ it may be generally available to all
customers, or only be available to those customers who have made a prior
arrangement.
.LP
	3.2
	\fINormal procedures\fR 
.LP
	The paragraphs under this heading describe the normal procedures
for activation, deactivation, registration, invocation and operation for the
service as appropriate. This section describes only the successful outcome 
of each procedure, and the procedures which are executed as a result of 
such 
successful outcomes. The procedures are described in a time\(hybased sequence 
of events. They describe the interactions of the users involved in the 
service 
with the service provider and with each other which lead to, and are elements 
of, the successful operation of the service. 
.LP
	3.2.1
	\fIActivation/deactivation/registration\fR 
.LP
	 The procedures for activation, which is the operation of bringing the 
service into the \*Qready for invocation\*U state, and deactivation, which 
is the complementary action, are described in this section. For some services 
there may be a specific user procedure to allow activation and deactivation 
as necessary, whilst for others the service is permanently activated on 
provision and thus no procedure is provided. 
.LP
	Registration describes the procedures by which any specific
information, necessary for the successful operation of the supplementary
service, is given to the network. The need to register information with the
network, e.g.\ a forwarding number, only applies to certain supplementary
services.
.LP
	3.2.2
	\fIInvocation and operation\fR 
.LP
	This section describes the procedures for invocation, which is
the action and conditions under which the service
.LP
is brought into operation; in the case of a supplementary service this may
only be on a particular call. It should be noted that although a supplementary 
service may be activated, it may not necessarily be invoked on all calls. 
(Invocation takes place either subsequent to or simultaneously with
activation.)
.LP
	In the case of basic services this section describes the events,
perceived at the service access point, during the establishment, information
transfer and clearing phases.
.LP
	Operation is the procedure which occurs once a service has been
invoked. In the case of a supplementary service this is described in terms 
of the way in which the supplementary service modifies/enhances 
the network's treatment of a call. This description gives details of the
significant actions of the network, treated in principle as a single entity,
and the perception of the users involved on the call. It includes details of
the information exchanged between the network and relevant users and the
indications given to each user, by the network, concerning the states of the
call.
.bp
.LP
	3.2.3
	\fIInterrogation/editing\fR 
.LP
	Interrogation is the facility which enables a served user to
determine, from the service provider, the current status of a particular
service. Whether this facility is provided for the service being described, 
and if so, the procedures that accompany it, are detailed in this section. 
.LP
	Editing describes the process whereby any registered information
(see section\ 3.2.1 under this \(sc\ A.2) specific to a service may be 
erased or 
modified by the served user.
.LP
	3.3
	\fIExceptional procedures\fR 
.LP
	 The paragraphs under this heading describe, for each of the items shown 
under section\ 3.2 of this \(sc\ A.2, the exceptional procedures which 
result in an unsuccessful outcome of the call. Included within this description 
are 
the details for such situations as invalid user action and the handling of
certain network and interface conditions. For the case of basic services 
this includes the handling of such network conditions as congestion. 
.LP
	3.4
	\fIAlternative procedures\fR 
.LP
	The paragraphs under this heading describe any alternative
procedures, where available, for each of the items shown under section\ 
3.2 of this \(sc\ A.2. 
These either allow an alternative way of activating or invoking the service, 
or detail a possible alternative treatment of the call by the network. 
.LP
	3.5
	\fIVerification\fR 
.LP
	This section describes the facilities that are provided by the
network to enable the subscriber to verify the operation of the service 
once it has been activated. Not all services allow provision for verification 
of the 
operation of the service.
.LP
	4
	\fINetworking capabilities for charging\fR 
.LP
	This section details only those charging aspects specific to the
service in question and includes, where necessary, both static (subscription) 
and dynamic (call related) aspects. 
.LP
	5
	\fIInterworking requirements\fR 
.LP
	 This section describes special aspects of the individual service, if 
the service is used in a connection which exists partly inside and partly 
outside a given ISDN, or which, for certain operational aspects, routes
through more than one ISDN.
.LP
	6
	\fIInteraction with other supplementary services\fR 
.LP
	 This section only applies in the case of supplementary services and describes 
all interactions of the supplementary service being described with 
other supplementary services as far as they have been identified and which 
are relevant for standardization. 
.LP
	For example, for some supplementary service pairs there is no
interaction as the two supplementary services are not permitted to be both 
in operation at the same time. For other pairs, one or both supplementary 
services may be modified whilst the pair of services are in operation simultaneously. 
.LP
	 It is recognized that although the layout, and the detailed work to date, 
has only dealt with the interactions between two supplementary services, 
further work is necessary on combinations of more than two supplementary 
services.
\v'1P'
.ce 1000
ANNEX\ B
.ce 0
.ce 1000
(to Recommendation I.210)
.sp 9p
.RT
.ce 0
.ce 1000
\fBList of attributes and their possible values for describing\fR 
.sp 1P
.RT
.ce 0
.ce 1000
\fBbearer services \(em Step 1.2 of description method\fR 
.ce 0
.ce 1000
\fB(Recommendation I.130)\fR 
.ce 0
.LP
B.1
	\fIFramework for the\fR 
\fIstatic description of bearer services\fR 
\fIsupported by an ISDN\fR 
.sp 1P
.RT
.PP
Static description of the service using attributes is the second
step (1.2) of the stage\ 1 overall service description from the user's 
point of view (Recommendation I.130). These attributes are described and 
defined in 
Recommendation I.140. Attributes to describe bearer services are intended 
to be independent and are grouped into three categories: 
.RT
.LP
	i)
	 \fIinformation transfer attributes\fR  | hich characterize the network 
capabilities for transferring information from one S/T reference 
point to one (or more) other S/T reference point(s), corresponding to access
points\ 2 and\ 1 as defined in Recommendation I.210;
.bp
.LP
	ii)
	\fIaccess attributes\fR  | hich describe the means for
accessing network functions or facilities as seen at one S/T reference 
point; and 
.LP
	iii)
	\fIgeneral attributes\fR  | hich deal with the service in general.
.PP
Figure B\(hy1/I.210 shows the relation between the groups of attributes 
and their fields of applicability. \(sc\ B.2 gives the list of the attributes. 
For the definitions and possible values of these attributes, see
Recommendation\ I.140.
.LP
.rs
.sp 16P
.ad r
\fBFigure B\(hy1/I.210, p.\fR 
.sp 1P
.RT
.ad b
.RT
.sp 1P
.LP
B.2
	\fIList of bearer service attributes\fR 
.sp 9p
.RT
.LP
	\fIInformation transfer attributes\fR 
.LP
	1.
	Information transfer mode
.LP
	2.
	Information transfer rate
.LP
	3.
	Information transfer capability
.LP
	4.
	Structure
.LP
\fR 	5.
	Establishment of communication
.LP
\fR 	6.
	Symmetry
.LP
\fR 	7.
	Communication configuration
.LP
\fR 	\fIAccess attributes\fR  | Note)
.LP
	8.
	Access channel and rate
.LP
\fR 	9.
	Access protocol
.LP
	\fIGeneral attributes\fR 
.LP
	10.
	Supplementary services provided
.LP
\fR 	11.
	Quality of Service
.LP
\fR 	12.
	Interworking possibilities
.LP
\fR 	13.
	Operational and commercial
.PP
\fINote\fR \ \(em\ Different access attributes may apply at each of the 
(two or more) network interfaces involved in the use of a bearer service. 
.PP
Table B\(hy1/I.210 presents a list of possible values for each
attribute. Where options exist for a given attribute, the selection is 
subject to agreement between the customer and the Administration. 
.PP
According to Recommendation I.210 the bearer capability defines the
technical features of a bearer service as they appear to the user at the S/T
reference point. The bearer capability is characterized by information 
transfer and access attributes. A bearer capability is associated with 
every bearer 
service.
.bp
.RT
.ce
\fBH.T. [1T3.210]\fR 
.ce
TABLE\ B\(hy1/I.210
.ce
\fBValues for each bearer service attribute\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(60p) | cw(168p) .
Attributes | ua\d\u)\d	Possible values of attributes
_
.T&
lw(60p) | lw(120p) | lw(48p) .
 {
\fIInformation transfer attributes\fR
 }	 {
1.
Information transfer mode
 }	
.T&
cw(60p) | cw(120p) | lw(48p) .
Circuit	Packet	
.TE
.TS
center box ;
lw(60p) | cw(30p) | cw(18p) | cw(24p) | cw(24p) | cw(24p) | cw(18p) | cw(30p) .
 {
3.
Information transfer capability
 }	 {
Unrestricted digital information
 }	Speech	3.1 kHz audio	7 kHz audio	15 kHz audio	Video	Others for further study
_
.T&
lw(60p) | cw(30p) | cw(66p) | cw(42p) | cw(12p) | cw(18p) .
4. Structure	8 kHz integrity	 {
Service data
unit integrity | ub\d\u)\d
 }	Unstructured	TSSI | uc\d\u)\d	RDTD | ud\d\u)\d
_
.T&
lw(60p) | cw(30p) | cw(66p) | cw(72p) .
 {
5.
Establishment of communication | ue\d\u)\d
 }	Demand	Reserved	Permanent
_
.T&
lw(60p) | cw(30p) | cw(66p) | cw(72p) .
6. Symmetry	Unidirectional	Bidirectional symmetric	Bidirectional asymmetric
_
.T&
lw(60p) | cw(30p) | cw(66p) | cw(72p) .
 {
7.
Communication configuration
 }	Point\(hyto\(hypoint	Multipoint	Broadcast | uf\d\u)\d
_
.T&
lw(60p) | cw(18p) | cw(12p) | cw(12p) | cw(18p) | cw(18p) | cw(18p) | cw(72p) .
 {
\fIAccess attributes\fR
8.
Access channel and rate
 }	D | 16)	D | 64)	B	H 0	H 1 1	H 1 2	Others for further study
_
.T&
lw(60p) | cw(18p) | cw(12p) | cw(24p) | cw(18p) | cw(24p) | cw(72p) .
 {
9.1
Signalling access 
protocol\ layer\ 1
 }	Rec. | .430/  Rec. I.431	Rec. I.461	Rec. I.462	Rec. I.463	(Rec. V.120)  Rec. I.465	Others for further study
_
.T&
lw(60p) | cw(30p) | cw(24p) | cw(18p) | cw(96p) .
 {
9.2
Signalling access 
protocol\ layer\ 2
 }	Rec. I.440/  Rec. I.441	Rec. I.462	Rec. X.25	Others for further study
_
.T&
lw(60p) | cw(30p) | cw(24p) | cw(18p) | cw(24p) | cw(24p) | cw(48p) .
 {
9.3
Signalling access 
protocol\ layer\ 3
 }	Rec. I.450/  Rec. I.451	Rec. I.461	Rec. I.462	Rec. X.25	Rec. I.463	Others for  further study
_
.T&
lw(60p) | cw(18p) | cw(12p) | cw(24p) | cw(18p) | cw(24p) | cw(12p) | cw(12p) | cw(12p) | cw(36p) .
 {
9.4
Information access 
protocol\ layer\ 1
 }	Rec. | .430/  Rec. I.431	Rec. I.460 | ug\d\u)\d	Rec. I.461	Rec. I.462	Rec. I.463	(Rec. V.120)  Rec. I.465	Rec. G.711	Rec. G.722	Others for  further study
_
.T&
lw(60p) | cw(18p) | cw(12p) | cw(24p) | cw(42p) | cw(72p) .
 {
9.5
Information access protocol layer\ 2
 }	HDLC LAPB	I.440/  I.441	Rec. X.25	Rec. I.462	Others for further study
_
.T&
lw(60p) | cw(18p) | cw(36p) | cw(42p) | cw(72p) .
 {
9.6
Information access protocol layer\ 3 | uh\d\u)\d
 }	T.70\(hy3	Rec. X.25	Rec. I.462	Others for further study
_
.T&
lw(60p) | cw(168p) .
 {
\fIGeneral attributes\fR
10.
Supplementary services provided
11.
Quality of service
12.
Interworking possibilities
13.
Operational and commercial aspects
 }	Under study  
_
.TE
.nr PS 9
.RT
.ad r
\fBTable B\(hy1 [1T3.210], p.\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.ce
\fBH.T. [2T3.210]\fR 
.ce
\fINotes to Table B\(hy1/I.210\fR 
.LP
\ua\d\u)\d
The attributes are intended to be independent of each
other.
.LP
\ub\d\u)\d
The need for a \*Qdata sequence integrity\*U attribute is
for further study.
.LP
\uc\d\u)\d
Time slot sequence integrity (TSSI).
.LP
\ud\d\u)\d
Restricted differential time delay (RDTD).
.LP
\ue\d\u)\d
A definition of the establishment of communication is
given in Recommendation I.140.
.LP
\uf\d\u)\d
The characterization of the information transfer
configuration attribute \*Qbroadcast\*U is for further study.
.LP
\ug\d\u)\d
The inclusion of Recommendation I.460 implies the support of
non\(hyISDN CCITT standardized services (e.g., at
X.1\ rate). The necessary user\(hynetwork signalling is provided in
Recommendation\ I.451.
.LP
\uh\d\u)\d
The use of Recommendation I.451 as an information access protocol
is for further study.
.ce
\fBH.T. [1T4.210]\fR 
.ce
TABLE\ C\(hy1/I.210
.ce
\fBPossible values for each teleservice attribute\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(60p) | cw(168p) .
Attributes | ua\d\u)\d	Possible values of attributes
_
.T&
lw(60p) | lw(120p) | lw(48p) .
 {
\fIInformation transfer attributes\fR
 }	 {
1.
Information transfer mode
 }	
.T&
cw(60p) | cw(120p) | lw(48p) .
Circuit	Packet	
_
.T&
lw(60p) | lw(12p) sw(108p) | lw(48p) , ^  | l | l | l.
		
			
.TE
.TS
center box;
lw(60p) | cw(30p) | cw(18p) | cw(24p) | cw(24p) | cw(72p) .
 {
3.
Information transfer capability
 }	 {
Unrestricted digital information
 }	Speech	3.1 kHz audio	7 kHz audio	Others for further study
_
.T&
lw(60p) | cw(30p) | cw(66p) | cw(42p) | cw(30p) .
4. Structure	8 kHz integrity	Service data  unit integrity	Unstructured	Others for further study
_
.T&
lw(60p) | cw(30p) | cw(66p) | cw(72p) .
 {
5.
Establishment of communication | ub\d\u)\d
 }	Demand	Reserved	Permanent
_
.T&
lw(60p) | cw(30p) | cw(66p) | cw(72p) .
6. Symmetry	Unidirectional	Bidirectional symmetric	Bidirectional asymmetric
_
.T&
lw(60p) | cw(30p) | cw(66p) | cw(72p) .
 {
7.
Communication configuration
 }	Point\(hyto\(hypoint	Multipoint	Broadcast | uc\d\u)\d
_
.T&
lw(60p) | cw(30p) | cw(36p) | cw(30p) | cw(72p) .
 {
\fIAccess attributes\fR
8.
Access channel and rate
 }	D | 16)	D | 64)	B	Others for further study
_
.T&
lw(60p) | cw(18p) | cw(12p) | cw(24p) | cw(18p) | cw(24p) | cw(72p) .
 {
9.1
Signalling access 
protocol\ layer\ 1
 }	Rec. | .430/  Rec. I.431	Rec. I.461	Rec. I.462	Rec. I.463	Rec. I.465  (Rec. V.120)	Others for further study
_
.T&
lw(60p) | cw(30p) | cw(24p) | cw(18p) | cw(96p) .
 {
9.2
Signalling access 
protocol\ layer\ 2
 }	Rec. I.440/  Rec. I.441	Rec. I.462	Rec. X.25	Others for further study
_
.T&
lw(60p) | cw(30p) | cw(24p) | cw(18p) | cw(24p) | cw(24p) | cw(48p) .
 {
9.3
Signalling access 
protocol\ layer\ 3
 }	Rec. I.450/  Rec. I.451	Rec. I.461	Rec. I.462	Rec. X.25	Rec. I.463	Others for  further study
_
.TE
.TS
center box;
lw(60p) | cw(18p) | cw(12p) | cw(24p) | cw(18p) | cw(24p) | cw(12p) | cw(12p) | cw(48p) .
 {
9.4
Information access protocol layer\ 1
 }	Rec. | .430/  Rec. I.431	Rec. I.460	Rec. I.461  (Rec. | .30)	Rec. I.462  (Rec. | .31)	Rec. I.463  (Rec. V.110)	Rec. I.465  (Rec. V.120)	Rec. G.711	Others for  further study
_
.T&
lw(60p) | cw(30p) | cw(24p) | cw(18p) | cw(24p) | cw(72p) .
 {
9.5
Information access protocol layer\ 2
 }	HDLC LAPB	Rec. | .440/  Rec. I.441	Rec. X.75 SLP	Rec. X.25 LAPB	Others for further study
_
.T&
lw(60p) | cw(54p) | cw(42p) | cw(72p) .
 {
9.6
Information access protocol layer\ 3
 }	 {
ISO 8208 | ud\d\u)\d
(Rec. X.25 PLP)
 }	Rec. X.25 PLP	Others for further study
_
.TE
.nr PS 9
.RT
.ad r
\fBTableau B\(hy1/I.210 [2T3.210], p. 10\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.sp 8
.ce 1000
ANNEX\ C
.ce 0
.ce 1000
(to Recommendation I.210)
.sp 9p
.RT
.ce 0
.ce 1000
\fBList of attributes and their possible values for describing\fR 
.sp 1P
.RT
.ce 0
.ce 1000
\fBteleservices\ \(em\ Step 1.2 of description method\fR 
.ce 0
.ce 1000
\fB(Recommendation I.130)\fR 
.ce 0
.LP
C.1
	\fIFramework for the\fR 
\fIstatic description of teleservices\fR 
\fIsupported by an ISDN\fR 
.sp 1P
.RT
.PP
A static description of the service using attributes is the second step 
(step\ 1.2) of the stage\ 1 overall service description from the user's 
point of view (Recommendation I.130). These attributes are described and
defined in Recommendation I.140.
.PP
Attributes to describe teleservices supported by an ISDN are
intended to be largely independent. They are grouped into three
categories:
.RT
.LP
	a)
	low layer attributes
.LP
	\(em
	information transfer attributes,
.LP
	\(em
	access attributes;
.LP
	b)
	high layer attributes;
.LP
	c)
	general attributes.
.PP
\fINote\fR \ \(em\ Teleservices generally make use of underlying lower 
layer capabilities of bearer services specified in the I.230\(hySeries 
of 
Recommendations. However, where teleservices are provided by a single
administration, RPOAs or other service providers, the combination of values 
of lower layer attributes applicable to specific teleservices may not necessarily 
be identical to any of those identified for the bearer services appearing 
in 
the I.230\(hySeries of Recommendations.
.PP
Figure C\(hy1/I.210 shows the relationship between the different
categories of service attributes and their scope within a teleservice.
.bp
.RT
.LP
.rs
.sp 17P
.ad r
\fBFigure C\(hy1/I.210, p.\fR 
.sp 1P
.RT
.ad b
.RT
.sp 1P
.LP
C.2
	\fIList of the teleservice attributes\fR 
.sp 9p
.RT
.LP
	\fILow layer attributes\fR 
.LP
	\fIInformation transfer attributes\fR 
.LP
	1.
	Information transfer mode
.LP
	2.
	Information transfer rate
.LP
\fR 	3.
	Information transfer capability
.LP
\fR 	4.
	Structure
.LP
\fR 	5.
	Establishment of communication
.LP
\fR 	6.
	Symmetry
.LP
\fR 	7.
	Communication configuration
.LP
	\fIAccess attributes\fR 
.LP
	8.
	Access channel and rate
.LP
\fR 	9.
	Access protocol
.LP
	9.1
	Signalling access protocol layer 1
.LP
\fR 	9.2
	Signalling access protocol layer 2
.LP
\fR 	9.3
	Signalling access protocol layer 3
.LP
\fR 	9.4
	Information access protocol layer 1
.LP
\fR 	9.5
	Information access protocol layer 2
.LP
\fR 	9.6
	Information access protocol layer 3
.LP
	\fIHigh layer attributes\fR 
.LP
	10.
	Type of user information
.LP
\fR 	11.
	Layer 4 protocol functions
.LP
\fR 	12.
	Layer 5 protocol functions
.LP
\fR 	13.
	Layer 6 protocol functions
.LP
	\(em
	Resolution
	?04
	\(em
	Graphic mode
	?05\ if applicable
	\(rb
.LP
	14.
	Layer 7 protocol functions
.LP
	\(em
	TE\(hyto\(hyTE protocol functions
	?04
	\(em
	TE\(hyto\(hyHLF protocol functions
	?05\ if applicable
(Note)
	\(rb
.LP
	\fIGeneral attributes\fR 
.LP
	15.
	Supplementary services provided
.LP
	16.
	Quality of Service
.LP
	17.
	Interworking possibilities
.LP
	18.
	Operational and commercial
.bp
.PP
\fINote\fR \ \(em\ These attribute values are shown in order to give an
example of a description of a teleservice appliction involving terminals at
both access points\ (3 or\ 5) and an intervening system providing HLF functions 
(see Figure\ 3\fIc\fR /I.210 and Figure\ 3\fIe\fR /I.210). A specific teleservice 
attribute description for this case is for further study. 
.PP
Table C\(hy1/I.210 presents a list of possible values for each service
attribute. Where optional values of given attributes are offered, their
selection is subject to agreement between the customer and service
provider.
.RT
.LP
.sp 2
.ce
\fBH.T. [1T4.210]\fR 
.ce
TABLE\ C\(hy1/I.210
.ce
\fBPossible values for each teleservice attribute\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(60p) | cw(168p) .
Attributes | ua\d\u)\d	Possible values of attributes
_
.T&
lw(60p) | lw(120p) | lw(48p) .
 {
\fIInformation transfer attributes\fR
 }	 {
1.
Information transfer mode
 }	
.T&
cw(60p) | cw(120p) | lw(48p) .
Circuit	Packet	
_
.T&
lw(60p) | lw(12p) sw(108p) | lw(48p) , ^  | l | l | l.
		
			
.TE
.TS
center box;
lw(60p) | cw(30p) | cw(18p) | cw(24p) | cw(24p) | cw(72p) .
 {
3.
Information transfer capability
 }	 {
Unrestricted digital information
 }	Speech	3.1 kHz audio	7 kHz audio	Others for further study
_
.T&
lw(60p) | cw(30p) | cw(66p) | cw(42p) | cw(30p) .
4. Structure	8 kHz integrity	Service data  unit integrity	Unstructured	Others for further study
_
.T&
lw(60p) | cw(30p) | cw(66p) | cw(72p) .
 {
5.
Establishment of communication | ub\d\u)\d
 }	Demand	Reserved	Permanent
_
.T&
lw(60p) | cw(30p) | cw(66p) | cw(72p) .
6. Symmetry	Unidirectional	Bidirectional symmetric	Bidirectional asymmetric
_
.T&
lw(60p) | cw(30p) | cw(66p) | cw(72p) .
 {
7.
Communication configuration
 }	Point\(hyto\(hypoint	Multipoint	Broadcast | uc\d\u)\d
_
.T&
lw(60p) | cw(30p) | cw(36p) | cw(30p) | cw(72p) .
 {
\fIAccess attributes\fR
8.
Access channel and rate
 }	D | 16)	D | 64)	B	Others for further study
_
.T&
lw(60p) | cw(18p) | cw(12p) | cw(24p) | cw(18p) | cw(24p) | cw(72p) .
 {
9.1
Signalling access 
protocol\ layer\ 1
 }	Rec. | .430/  Rec. I.431	Rec. I.461	Rec. I.462	Rec. I.463	Rec. I.465  (Rec. V.120)	Others for further study
_
.T&
lw(60p) | cw(30p) | cw(24p) | cw(18p) | cw(96p) .
 {
9.2
Signalling access 
protocol\ layer\ 2
 }	Rec. I.440/  Rec. I.441	Rec. I.462	Rec. X.25	Others for further study
_
.T&
lw(60p) | cw(30p) | cw(24p) | cw(18p) | cw(24p) | cw(24p) | cw(48p) .
 {
9.3
Signalling access 
protocol\ layer\ 3
 }	Rec. I.450/  Rec. I.451	Rec. I.461	Rec. I.462	Rec. X.25	Rec. I.463	Others for  further study
_
.TE
.TS
center box;
lw(60p) | cw(18p) | cw(12p) | cw(24p) | cw(18p) | cw(24p) | cw(12p) | cw(12p) | cw(48p) .
 {
9.4
Information access protocol layer\ 1
 }	Rec. | .430/  Rec. I.431	Rec. I.460	Rec. I.461  (Rec. | .30)	Rec. I.462  (Rec. | .31)	Rec. I.463  (Rec. V.110)	Rec. I.465  (Rec. V.120)	Rec. G.711	Others for  further study
_
.TE
.TS
center box;
lw(60p) | cw(30p) | cw(24p) | cw(18p) | cw(24p) | cw(72p) .
 {
9.5
Information access protocol layer\ 2
 }	HDLC LAPB	Rec. | .440/  Rec. I.441	Rec. X.75 SLP	Rec. X.25 LAPB	Others for further study
_
.T&
lw(60p) | cw(54p) | cw(42p) | cw(72p) .
 {
9.6
Information access protocol layer\ 3
 }	 {
ISO 8208 | ud\d\u)\d
(Rec. X.25 PLP)
 }	Rec. X.25 PLP	Others for further study
_
.TE
.nr PS 9
.RT
.ad r
\fBTable C\(hy1 [1T4.210], p.\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.ce
\fBH.T. [2T4.210]\fR 
.ce
TABLE\ C\(hy1/I.210 | fI(cont.)\fR 
.ce
\fBPossible values for each teleservice attribute\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(60p) | cw(168p) .
Attributes | ua\d\u)\d	Possible values of attributes
_
.TE
.TS
center box;
lw(60p) | cw(12p) | cw(18p) | cw(24p) | cw(18p) | cw(24p) | cw(18p) | cw(12p) | cw(24p) | cw(18p) .
10. Type of user information	Speech  (telephony)	Sound	Text  (Teletex)	Facsimile  (Telefax | )	 {
Text\(hy
facsimile
(Mixed mode)
 }	Videotex	Video	Text interactive  (Telex)	Other
_
.TE
.TS
center box;
lw(60p) | cw(54p) | cw(42p) | cw(72p) .
11. Layer 4 protocol	Rec. X.224	Rec. T.70	Others for further study
_
12. Layer 5 protocol	Rec. X.225	Rec. T.62	Others for further study
_
.TE
.TS
center box;
lw(60p) | cw(30p) | cw(24p) | cw(18p) | cw(24p) | cw(72p) .
13. Layer 6 protocol	T.400\(hySeries	Rec. G.711	Rec. T.61	Rec. T.6	Others for further study
_
.T&
lw(60p) | cw(30p) | cw(24p) | cw(18p) | cw(24p) | cw(72p) .
 {
Resolution | ue\d\u)\d\ \uf\d\u)\d
 }	200  ppi	240  ppi	300  ppi	400  ppi	Others for further study
_
.T&
lw(60p) | cw(18p) | cw(36p) | cw(42p) | cw(72p) .
Graphic mode | uf\d\u)\d	Alpha\(hymosaic	Geometric	Photographic	Others for further study
_
.T&
lw(60p) | cw(54p) | cw(42p) | cw(72p) .
14. Layer 7 protocol	Rec. T.60	T.500\(hySeries	Others for further study
_
.T&
lw(60p) | cw(168p) .
\fIGeneral attributes\fR	Under study
.TE
.IP SLP
Single link protocol
.IP PLP
Packet layer protocol
.IP ppi
Picture elements per inch
.LP
\ua\d\u)\d
The attributes are intented to be independent of each
other.
.LP
\ub\d\u)\d
A definition of the establishment of communication is
given in Recommendation I.140.
.LP
\uc\d\u)\d
The characterization of the information transfer configuration
attribute \*Qbroadcast\*U is for further study.
.LP
\ud\d\u)\d
For those teleservices that use circuit mode bearer
capability X.25 PLP description is as per
ISO\ 8208.
.LP
\ue\d\u)\d
These attribute values are mentioned in order to give an example
of a specific presentation description of characteristics such as
coding of the user information, resolution, and graphic mode.
Attribute values for other presentation characteristics
are for further study.
.LP
\uf\d\u)\d
If applicable.
.nr PS 9
.RT
.ad r
\fBTableau C\(hy1/I.210 [2T4.210], p. 13\fR 
.sp 1P
.RT
.ad b
.RT
.ce 1000
ANNEX\ D
.ce 0
.ce 1000
(to Recommendation I.210)
.sp 9p
.RT
.ce 0
.ce 1000
\fBDynamic description of the service using graphic means\ \(em\fR 
.sp 1P
.RT
.ce 0
.ce 1000
\fBStep 1.3 of description method\fR 
.ce 0
.ce 1000
\fB(Recommendation I.130)\fR 
.ce 0
.LP
D.1
	\fIIntroduction\fR 
.sp 1P
.RT
.PP
Dynamic description of the service using graphic means is the third step 
(1.3) of the stage\ 1 overall service description from the user's point 
of view (Recommendation I.130). 
.PP
The dynamic description of a service contains all the information that 
is sent and received by the user from activationB/Finvocation of the service 
to completion of the service. The information is presented in the form 
of an 
Overall Specification and Description Language (SDL) diagram or state
transition diagrams.
.bp
.PP
\fINote\fR \ \(em\ Currently, state transition diagrams are not used for the
dynamic descriptions of services.
.PP
An overall SDL diagram shows the flow of events and states within the service, 
in a time\(hysequenced format, and identifies all possible actions 
relevant to the service as perceived by the user. It treats the network as a
single entity, that is, no information flows between nodes within the network 
are considered. 
.PP
SDL diagrams
, drawn according to the principles laid down in Recommendation\ Z.100, 
are included in step 1.3 in order to help to clarify and support the processing 
and information flows necessary for each service. 
.RT
.sp 1P
.LP
D.2
	\fIOverall specifications and description language (OSDL) diagrams\fR 
.sp 9p
.RT
.PP
In this third step of stage 1 each service state is shown in
conjunction with all the external or internal actions which cause state
changes. The actions may be inputs from users or the outcome of an internal
process. Ideally all situations are included in a single diagram although 
the diagram may have to be distributed over more than one document because 
of its complexity. 
.PP
The symbols used in OSDL diagrams and their meanings are as
follows:
.RT
.LP
.rs
.sp 36P
.ad r
\fBDiagramme T1806920\(hy88, p. 14\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.LP
.rs
.sp 47P
.ad r
\fBDiagramme T1806930\(hy88, p. 15\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.LP
\fBMONTAGE : PAGE 126 = PAGE BLANCHE\fR 
.sp 1P
.RT
.LP
.bp
.sp 1P
.ce 1000
\v'3P'
SECTION\ 2
.ce 0
.sp 1P
.ce 1000
\fBCOMMON\ ASPECTS\ OF\ SERVICES\ IN\ THE\ ISDN\fR 
.ce 0
.sp 1P
.sp 2P
.LP
\fBRecommendation\ I.220\fR 
.RT
.sp 2P
.ce 1000
\fBCOMMON\ DYNAMIC\ DESCRIPTION\ OF\ BASIC\fR 
.EF '%	Fascicle\ III.7\ \(em\ Rec.\ I.220''
.OF '''Fascicle\ III.7\ \(em\ Rec.\ I.220	%'
.ce 0
.sp 1P
.ce 1000
\fBTELECOMMUNICATION\ SERVICES\fR 
.ce 0
.sp 1P
.ce 1000
\fI(Melbourne, 1988)\fR 
.sp 9p
.RT
.ce 0
.sp 1P
.LP
\fB1\fR 	\fBIntroduction\fR 
.sp 1P
.RT
.PP
This Recommendation provides the dynamic description of basic
telecommunication services. The dynamic description for basic telecommunication 
services using the circuit\(hymode means of service 
establishment/dis
establishment
is provided in \(sc\ 2. The packet\(hymode description is for further study.
.PP
The dynamic description shows the flow of events, and states within
.PP
the service, in a time\(hysequenced format and identifies all possible actions
relevant to the service as perceived by end\(hyusers.
.PP
Although the service is described from the end\(hyuser perspective it does 
not concern details of the human\(hyto\(hymachine interface itself. In 
addition, the service description considers the network as a single entity. 
For example, 
information flows between nodes within the network are not shown.
.PP
End\(hyuser perceptions of the service are shown in terms of
\*Quser/network\*U interactions
. Internal network actions are included
whenever they are or can be perceived by an end\(hyuser during the operation of
the service, and as required by SDL drawing rules.
.PP
The terminology and the meaning of the \*Quser/network\*U interactions 
are provided in Annex\ A. The means for developing dynamic descriptions, 
e.g. the 
SDL symbols and their usage, is further elaborated in Recommendation\ I.210.
.PP
\fINote\fR \ \(em\ In the development of the circuit\(hymode dynamic description, 
the bearer services (speech,\ 3.1\ kHz audio, unrestricted) and the teleservices 
(telephony, Teletex, Telefax\ 4, mixed\(hymode and Videotex) were considered. 
Others are for further study.
.RT
.sp 2P
.LP
\fB2\fR 	\fBCircuit\(hymode dynamic description of basic bearer services\fR 
\fBand teleservices\fR 
.sp 1P
.RT
.PP
See Annex\ A for terminology used in Figures 1/I.220 to 6/I.220.
.PP
In Figures 1/I.220 to 6/I.220, the following notes are common:
.PP
\fINote\ 1\fR \ \(em\ This is an event which may occur at the S/T reference
point and can be reflected at the user interface.
.PP
\fINote\ 2\fR \ \(em\ This is an event which may occur at the S/T reference 
point but is not reflected at the user interface. 
.PP
\fINote\ 3\fR \ \(em\ In some networks this decision is optional, that is,
multipoint operation is assumed.
.bp
.RT
.LP
.rs
.sp 27P
.ad r
\fBFigure 1/I.220, p. 16\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.rs
.sp 21P
.ad r
\fBFigure 2/I.220, p. 17\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.LP
.rs
.sp 47P
.ad r
\fBFigure 3/I.220, p. 18\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.LP
.rs
.sp 43P
.ad r
\fBFigure 4/I.220 (feuillet 1 sur 4), p. 19\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.LP
.rs
.sp 47P
.ad r
\fBFigure 4/I.220 (feuillet 2 sur 4), p. 20\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.LP
.rs
.sp 47P
.ad r
\fBFigure 4/I.220 (feuillet 3 sur 4), p. 21\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.LP
.rs
.sp 47P
.ad r
\fBFigure 4/I.220 (feuillet 4 sur 4), p. 22\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.LP
.rs
.sp 47P
.ad r
\fBFigure 5/I.220, p. 23\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.LP
.rs
.sp 32P
.ad r
\fBFigure 6/I.220, p. 24\fR 
.sp 1P
.RT
.ad b
.RT
.ce 1000
ANNEX\ A
.ce 0
.ce 1000
(to Recommendation I.220)
.sp 9p
.RT
.ce 0
.ce 1000
\fBTerminology for \*Quser/network\*U interactions\fR 
.sp 1P
.RT
.ce 0
.LP
\fR SETUP
	Interaction across the \*Quser/network\*U interface regarding a
service request.
.sp 1P
.RT
.LP
REPORT
	 Interaction across the \*Quser/network\*U interface regarding alerting 
of the user's terminal function, interworking whih a non\(hyISDN network, 
or 
routing progress.
.LP
CONNECT
	Interaction across the \*Quser/network\*U interface regarding
completion of circuit cut\(hythrough.
.LP
DISCONNECT
	 Interaction across the \*Quser/network\*U interface regarding a user 
who has disconnected, or regarding a user A who cannot be connected (e.g.\ 
busy) to a user B. 
.LP
RELEASE
	 Interaction across the \*Quser/network\*U interface regarding freeing 
of resources associated with the call/connection, such as call references 
and channels. 
.LP
NDUB
	Network determined user busy.
.LP
UDUB
	User determined user busy.
.bp
.sp 2P
.LP
\fBRecommendation\ I.221\fR 
.RT
.sp 2P
.sp 1P
.ce 1000
\fBCOMMON\ SPECIFIC\ \fR \fBCHARACTERISTICS\ OF\ SERVICES\fR 
.EF '%	Fascicle\ III.7\ \(em\ Rec.\ I.221''
.OF '''Fascicle\ III.7\ \(em\ Rec.\ I.221	%'
.ce 0
.sp 1P
.ce 1000
\fI(Melbourne, 1988)\fR 
.sp 9p
.RT
.ce 0
.sp 1P
.LP
\fB1\fR 	\fBIntroduction\fR 
.sp 1P
.RT
.PP
The principles of telecommunication services supported by an ISDN and the 
means to describe them are given in Recommendation\ I.210. 
.PP
The attribute technique and values of attributes, which form part of the 
standardized description method, (see Recommendation\ I.130) for services, 
are given in Recommendation\ I.140. 
.PP
This Recommendation refers to and details the common specific
characteristics of services for both basic services and supplementary
services.
.RT
.sp 2P
.LP
\fB2\fR 	\fBScope and content of the Recommendation\fR 
.sp 1P
.RT
.PP
This Recommendation identifies and describes those common specific
characteristics of services which are a common feature of each of the
individual services and which help to form a relationship between services.
.PP
These characteristics are used in a consistent manner throughout the
ISDN services and are intended to be service independent. They are used, for
instance, to help to identify the situations under which certain supplementary 
services are invoked during the operation of basic services. 
.RT
.LP
\fB3\fR 	\fBCommon specific characteristics\fR 
.sp 1P
.RT
.sp 2P
.LP
3.1
	\fIDefinition of\fR 
\fI\*Qbusy\*U in an ISDN\fR 
.sp 1P
.RT
.sp 1P
.LP
3.1.1
	\fIScope\fR 
.sp 9p
.RT
.PP
This section describes the conditions under which a given ISDN
destination is considered \*Qbusy\*U. In general, this occurs whenever the
resources associated with that destination (and needed to successfully 
complete the call) exist but are not available for the call. In existing 
networks, such as the PSTN, this is indicated to the calling subscriber 
by \*Qbusy tone\*U. 
.PP
In addition, the operation of certain ISDN supplementary services occurs 
when certain of these resources are busy. Therefore, these \*Qresource 
busy\*U 
conditions are also described herein.
.PP
This section does not cover the cases where network resources not
associated with a given destination are unavailable, or when such resources 
are out\(hyof\(hyservice or otherwise non\(hyfuntional. 
.RT
.sp 1P
.LP
3.1.2
	\fIResources\fR 
.sp 9p
.RT
.PP
Two main categories of resources may become involved in the
determination of \*Qbusy\*U: interface resources and customer resources.
.PP
\fIInterface resources\fR  | nclude the signalling channel
(D\(hychannel), other physical channels (B\(hy and H\(hychannels), logical 
channels (for packet\(hymode services) and maximum number of calls supported. 
It is noted that with the ongoing activities on \*Qcalls versus connections\*U 
other interface 
resources may become important in the future.
.PP
For the purposes of this Recommendation, the signalling channel is
considered to be always available and with sufficient capacity to handle
signalling for new calls. Situations where this is not true are considered 
to be \*Qfailure conditions\*U and are not covered here. For the other 
interface 
resources, descriptions are given below of what is meant when they are
considered busy.
.PP
\fISubscriber resources\fR  | nclude the terminal(s) themselves and the 
persons or processes using them. For the purposes of this Recommendation, 
it is not considered significant which of the subscriber resources are 
busy, or why. An indication from the subscriber that (some, necessary) 
subscriber 
resources are busy is sufficient.
.bp
.RT
.sp 1P
.LP
3.1.3
	\fIResource busy conditions\fR 
.sp 9p
.RT
.PP
Three resource busy conditions have been found necessary to refer
to and are defined below:
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	1)
	channels busy: this condition occurs when there is no
appropriate information channel (physical or logical) available for the 
network to use for the call. 
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	2)
	 maximum number of total calls reached: this condition occurs when the 
maximum number of total calls supported at the given subscriber's 
interface(s) has been reached.
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	3)
	subscriber busy: this condition is indicated by the
subscriber's terminal equipment, e.g. by having all compatible terminals 
which could respond to the call request indicate \*Quser busy\*U either 
when they are 
offered a call, or in response to an enquiry from the network.
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3.1.4
	\fIProcedural aspects\fR 
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The resource busy conditions described above significantly influence the 
call offering procedures, both for the basic ISDN calls and for calls that 
may involve ISDN supplementary services. The procedural aspects of call 
offering are outlined below and shown in Figure\ 1/I.221.
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	1)
	 Assume that a call of a telecommunications service subscribed to by the 
called subscriber is about to be offered. 
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	2)
	 If all of the appropriate user\(hynetwork interface information channels 
are busy (i.e. channels busy) and either the network does not support the 
offering of additional calls beyond the number of appropriate channels, 
or the maximum number of such additional calls has been reached, the network 
will clear the call [see also item\ 7, below] and indicate \*Qnetwork determined 
user busy\*U back towards the calling subscriber. 
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	3)
	 Similarly, if the maximum number of total calls supported at the given 
subscriber's interface(s) has been reached, the network will clear 
the call (see also item\ 7 below) and indicate \*Qnetwork determined user 
busy\*U 
back towards the calling subscriber.
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	4)
	Otherwise, the network offers the call to the subscriber.
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	5)
	 If any compatible terminal responds \*Qpositively\*U to the call offering, 
i.e. gives some indication that the call may progress towards 
successful completion, the normal call offering procedure should continue.
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	6)
	If no compatible terminal responds \*Qpositively\*U but one or
more compatible terminal responds \*Quser busy\*U, then when the
response\(hyto\(hycall\(hyoffering timeout occurs, the network will clear 
the call with the indication \*Quser determined user busy\*U. 
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	7)
	It is recognized that for the determination of a \*Qnetwork
determined user busy\*U condition, the network does not assume any knowledge 
of whether or not a compatible terminal exists at the called interface. 
This may mask the determination of a \*Qno compatible terminal available\*U 
condition, i.e. a NDUB condition may be returned when, in fact, no compatible 
terminal is 
connected. The use of an explicit compatibility check to prevent this from
occuring is a service provider option and is for further study.
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3.1.5
	\fIDefinition of\fR \fBbusy\fR 
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An ISDN destination is considered to be busy if either a \*Qnetwork
determined user busy\*U or a \*Quser determined user busy\*U condition 
occurs, as 
described above.
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\fBFigure 1/I.221, p. 25\fR 
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