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.EN
.nr LL 40.5P
.nr ll 40.5P
.nr HM 3P
.nr FM 6P
.nr PO 4P
.nr PD 9p
.po 4P

.rs
\v | 5i'
.sp 1P
.ce 1000
\v'12P'
\s12FASCICLE\ VI.9
\v'4P'
.RT
.ce 0
.sp 1P
.ce 1000
\fBRecommendations Q.771 to Q.795\fR \v'2P'
.ce 0
.sp 1P
.ce 1000
\fBSPECIFICATIONS\ OF\fR 
.ce 0
.sp 1P
.ce 1000
\fBSIGNALLING\ SYSTEM\ No.\ 7\fR 
.ce 0
.sp 1P
.LP
.rs
.sp 28P
.ad r
Blanc
.ad b
.RT
.LP
.bp
.LP
\fBMONTAGE:\ \fR PAGE 2 = PAGE BLANCHE
.sp 1P
.RT
.LP
.EF '%	Fascicle\ VI.9\ \(em\ Rec.\ Q.771''
.OF '''Fascicle\ VI.9\ \(em\ Rec.\ Q.771	%'
.LP
.bp
.sp 1P
.ce 1000
\v'3P'
SECTION\ 1
.ce 0
.sp 1P
.ce 1000
\fBTRANSACTION CAPABILITIES APPLICATION PART (TCAP)\fR 
.ce 0
.sp 1P
.sp 2P
.LP
\fBRecommendation\ Q.771\fR 
.RT
.sp 2P
.sp 1P
.ce 1000
\fBFUNCTIONAL DESCRIPTION OF TRANSACTION CAPABILITIES\fR 
.EF '%	Fascicle\ VI.9\ \(em\ Rec.\ Q.771''
.OF '''Fascicle\ VI.9\ \(em\ Rec.\ Q.771	%'
.ce 0
.sp 1P
.LP
\fB1\fR 	\fBIntroduction\fR 
.sp 1P
.RT
.sp 1P
.LP
1.1
	\fIGeneral\fR 
.sp 9p
.RT
.PP
Transaction Capabilities (TC) provide functions and protocols to a large 
variety of applications distributed over exchanges and specialized 
centres in telecommunication networks.
.PP
The support of TC by terminal equipments is for further study.
.PP
The term \*QTransaction Capabilities\*U refers to Application layer
services and protocols, called Transaction Capabilities Application Part,
or\ TCAP, plus any supporting Presentation, Session and Transport layers
services and protocols, called the Intermediate Service Part, or ISP.
.PP
To date, only Signalling System\ No.\ 7 MTP plus SCCP have been
considered as network layer service providers. However, any standard OSI
Network Layer might be used in place of the MTP plus SCCP, provided that the
requirements of the applications supported by TC (e.g.\ service and performance 
requirements) can be met. This area requires further study. 
.PP
Figure 1/Q.771 shows the general structure of TC. It shows that the
Transaction Capabilities Application Part (TCAP) forms a part of layer\ 
7 of the OSI Reference Model. The remainder of layer\ 7 is referred to 
as a TC\(hyuser. The Intermediate Service Part (ISP) covers layers\ 4 to\ 
6. 
.RT
.PP
Figure 2/Q.771 illustrates the situation of TC in the\ No.\ 7
Signalling System.
.sp 1P
.LP
1.2
	\fIContents of the Recommendations Series Q.771\(hyQ.775\fR 
.sp 9p
.RT
.PP
Recommendation Q.771 contains a general description of the services provided 
by the Transaction Capabilities, and the service expected from the 
SCCP.
.PP
Recommendation Q.772 defines the Transaction Capabilities Information Elements, 
and their functions. 
.PP
Recommendation Q.773 defines the formats and encoding used for the
Transaction Capabilities Messages. Annex\ A specifies the protocol data units
using the ASN.1 formal notation (Recommendations\ X.208/X.209).
.PP
Recommendation Q.774 specifies the Transaction Capabilities
procedures. Annex\ A to this Recommendation contains SDL diagrams for\ TC.
.PP
Recommendation Q.775 contains guidelines and examples on how to define 
applications and their use of TC. 
.bp
.RT
.LP
.rs
.sp 29P
.ad r
\fBFigure 1/Q.771, p.  \fR 
.sp 1P
.RT
.ad b
.RT
.LP
.rs
.sp 17P
.ad r
\fBFigure 2/Q.771, p.  \fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.PP
The present Recommendation contains both introductory information (chapters\ 
1 and\ 2), and a detailed description (chapters\ 3 and\ 4), using 
primitives, of the services provided by TC. The reader interested in the 
first aspect only may read the first two chapters only; chapters\ 3 and 
on contain 
more detailed information.
.RT
.sp 2P
.LP
1.3
	\fIObjectives\fR 
.sp 1P
.RT
.sp 1P
.LP
1.3.1
	\fIDefinition of Transaction Capabilities\fR 
.sp 9p
.RT
.PP
The overall objective of Transaction Capabilities is to provide the means 
for the transfer of information between nodes, and to provide generic 
services to applications, while being independent of any of these.
.RT
.sp 1P
.LP
1.3.2
	\fIScope of Transaction Capabilities\fR 
.sp 9p
.RT
.PP
Transaction Capabilities in a Signalling System\ No.\ 7 network
should be considered for use between:
.RT
.LP
	1)
	exchanges
.LP
	2)
	an exchange and a network service centre (e.g.\ data base,
specialized facility unit, OA&M Centre).
.LP
	3)
	network service centres.
.PP
The following applications have been recognized as TC\(hyusers:
.LP
	\(em
	mobile service application (e.g.\ location of roamers)
.LP
	\(em
	registration, activation and invocation of supplementary
services involving specialized facility units (e.g.\ freephone service credit
card service)
.LP
	\(em
	non circuit control\(hyrelated exchange of signalling
information (e.g.\ closed user group, look\(hyahead procedure)
.LP
	\(em
	 operation and maintenance applications (e.g.\ query/response, bulk data 
transfer). 
.PP
This list is not exhaustive.
.PP
These applications can be classified into two broad
categories:
.RT
.LP
	\(em
	real\(hytime sensitive, with small amounts of data to be
transferred
.LP
	\(em
	 less real\(hytime sensitive, with possibly large amounts of data to be 
transferred. 
.PP
A more precise definition of the boundary between these two
categories requires further study. A given application is not compelled to
belong to only one of these categories.
.PP
TC services offered to applications in the first category are based on 
a connectionless network service. They are introduced in\ \(sc\ 2.3, and 
further 
described in chapter\ 3 of this Recommendation.
.PP
TC services offered to applications in the second category are based on 
a connection\(hyoriented network service. They are introduced in\ \(sc\ 
2.4, and 
further described in chapter\ 4 of this Recommendation.
.PP
The mechanism for selecting a category is for further study.
.RT
.sp 2P
.LP
\fB2\fR 	\fBOverview\fR 
.sp 1P
.RT
.sp 1P
.LP
2.1
	\fITerminology\fR 
.sp 9p
.RT
.PP
The following terms are used throughout the\ Q.77x Series of
Recommendations and are defined in the Signalling System\ No.\ 7 glossary: 
class of operation; component correlation; component portion; dialogue; 
information element; Intermediate Service Part; linked operation; operation; 
reply; result; tag; transaction; Transaction Capabilities; Transaction 
Capabilities 
Application Part; transaction portion.
.RT
.sp 2P
.LP
2.2
	\fIStructure of TC\fR 
.sp 1P
.RT
.sp 1P
.LP
2.2.1
	\fIArchitectural concepts\fR 
.sp 9p
.RT
.PP
The OSI protocol reference model (Recommendation\ X.200) is used to  model\ TC.
.bp
.PP
From an end\(hyuser point of view, Transaction Capabilities for initially 
planned services lie within the Network layer of the OSI model. Provision 
of 
network layer services to end\(hyusers requires communication between TC\(hyusers 
at various network nodes; these intra\(hynetwork communications may in 
turn be 
modelled using the\ 7\(hylayer reference model of OSI.
.PP
TCAP is structured in two sub\(hylayers:
.RT
.LP
	\(em
	 the component sub\(hylayer, which deals with individual actions or data, 
called components 
.LP
	\(em
	 the transaction sub\(hylayer, which deals with the exchange of messages 
cotaining components between two TC\(hyusers. 
.PP
This is illustrated by Figure 3/Q.771.
.LP
.rs
.sp 17P
.ad r
\fBFigure 3/Q.771, p.  \fR 
.sp 1P
.RT
.ad b
.RT
.sp 1P
.LP
2.2.2
	\fIAddressing issues\fR 
.sp 9p
.RT
.PP
When TC uses the Signalling System\ No.\ 7 network service, the
addressing options supported by the SCCP are used.
.PP
When other network layer service providers are used, the addressing
options supported by these providers will be used; further study on this 
area is required. 
.RT
.sp 1P
.LP
2.2.3
	\fIManagement aspects\fR 
.sp 9p
.RT
.PP
For further study.
.RT
.sp 1P
.LP
2.2.4
	\fIAlignment of TCAP with X.219 and X.229 (ROSE)\fR 
.sp 9p
.RT
.PP
The Component sub\(hylayer of TCAP is in partial alignment with the
capabilities of the Remote Operation Service Element\ (ROSE). The current
status of TCAP and ROSE alignment is on the basis of protocol alignment, 
namely the\ X.229 protocol is contained within the TCAP component protocol. 
In 
addition, the Component sub\(hylayer includes some extensions to ROSE. Service
alignment on the primitive interface to TC/ROSE users is for further study.
.PP
The X.219 Remote Operation Service provides five classes of
operations. Class\ 1 is synchronous, reporting both success and failure.
Classes\ 2 to\ 5 are asynchronous and correspond to the TCAP operation 
classes\ 1 to\ 4. TCAP has not adopted ROSE class\ 1 (synchronous), because 
the full\(hyduplex mode of operation is used in TCAP. TC\(hyusers may use 
the TCAP operation class\ 1 in a synchronous mode if appropriate. Further 
details are given in 
Recommendation\ Q.775.
.bp
.RT
.sp 2P
.LP
2.3
	\fITC Based on a Connectionless Network Service\fR 
.sp 1P
.RT
.sp 1P
.LP
2.3.1
	\fIArchitecture\fR 
.sp 9p
.RT
.PP
This chapter defines a class of TC services based on a
connectionless network service, in this case, no functionality is provided 
by the ISP, and TCAP interfaces directly with the SCCP, as represented 
on 
Figure\ 4/Q.771.
.PP
The class of TC services is selected by the TC\(hyuser on the basis of 
a Quality of Service parameter. 
.RT
.LP
.rs
.sp 16P
.ad r
\fBFigure 4/Q.771, p.  \fR 
.sp 1P
.RT
.ad b
.RT
.sp 2P
.LP
2.3.2
	\fIService Provided by the Component Sub\(hylayer\fR 
.sp 1P
.RT
.sp 1P
.LP
2.3.2.1
	\fIComponent\fR 
.sp 9p
.RT
.PP
A component consists of a request to perform an \fBoperation\fR , or a 
\fBreply\fR . 
.PP
An operation is an action to be performed by the remote end. It may
have associated parameters. An invocation of an operation is identified by a
component\ ID; this allows several invocations of the same or different
operations to be active simultaneously.
.PP
One or more replies may be sent to an operation.
.PP
The ability for TC\(hyusers to exchange components which are neither
operation invocations, nor replies, is for further study.
.PP
Components are passed individually between a TC\(hyuser and the Component 
sub\(hylayer. The originating TC\(hyuser may send several components to 
the Component sub\(hylayer before these are transmitted (in a single message) 
to the remote end. Whenever several components are received in a single 
message, each one is 
delivered individually to the destination TC\(hyuser.
.PP
Components in a message are delivered to the remote TC\(hyuser in the
same order as they are provided at the originating interface. The importance 
of the order is by prior agreement between the TC\(hyusers involved. 
.RT
.sp 1P
.LP
2.3.2.2
	\fIDialogue\fR 
.sp 9p
.RT
.PP
Successive components exchanged between two TC\(hyusers in order to
perform an application constitute a dialogue. The Component sub\(hylayer 
provides dialogue facilities, allowing several dialogues to run concurrently 
between two given TC\(hyusers. 
.PP
Two kinds of facilities are provided: unstructured and
structured.
.bp
.RT
.sp 1P
.LP
2.3.2.2.1\ \ 
\fIUnstructured dialogue\fR 
.sp 9p
.RT
.PP
TC\(hyusers send components that do not expect replies without forming 
an explicit association between themselves. This is referred to as the 
unstructured dialogue case. The implicit association always exists between 
the communicating TC\(hyusers. When one TC\(hyuser sends a unidirectional 
message to its peer, this indicates use of the unstructured dialogue facility. 
A TC\(hyuser may have any number of operations active at any given time, 
the maximum number is dependent on the unique invoke IDs available to it 
at any time. 
.PP
When a TC\(hyuser is a receiver of a unidirectional message, if a
protocol error is to be reported, it is also returned in a unidirectional
message.
.RT
.sp 1P
.LP
2.3.2.2.2\ \ 
\fIStructured dialogue\fR 
.sp 9p
.RT
.PP
Alternatively, TC\(hyusers indicate the beginning, or the formation
of an association, the continuation, and the end of a dialogue; this is
referred to as a structured dialogue. Using a structured dialogue allows two
TC\(hyusers to run several dialogues concurrently, each being identified by a
particular dialogue\ ID. Each dialogue ID has a separate invoke ID name 
space, thus allowing duplication of invoke IDs in different dialogues. 
In sequence 
delivery of messages may be provided by means of application protocols, 
or by use of the appropriate class of service. 
.PP
When using the structured dialogue service, the TC\(hyuser has to
indicate one of the following three possibilities when sending a component 
to its peer entity: 
.RT
.LP
	i)
	a dialogue begins;
.LP
	ii)
	a dialogue continues: full\(hyduplex exchange of components is possible;
.LP
	iii)
	a dialogue ends: the sending side will not send more
components, nor will it accept any more components from the remote end.
.sp 1P
.LP
2.3.2.3
	\fIComponent Correlation\fR 
.sp 9p
.RT
.PP
The Component sub\(hylayer provides the following
facilities:
.RT
.LP
	a)
	association of operations and replies
.LP
	The value of the invoke ID, which identifies an operation
invocation without ambiguity, is returned in a reply to that invocation.
.LP
	Four classes of operations are considered:
.LP
	\(em
	class 1: both success and failure are reported
.LP
	\(em
	class 2: only failure is reported
.LP
	\(em
	class 3: only success is reported
.LP
	\(em
	class 4: neither success, nor failure is
reported.
.LP
	The replies to an operation consist of one or more components.
Where necessary, the TC\(hyuser provides segmentation of a successful result. 
In addition, any number of linked operations may be sent prior to the last 
component of the reply.
.LP
	 Any kind of component, except a reject component, may be rejected. Rejection 
of a result causes termination of the corresponding operation; 
rejection of a linked operation does not affect the linked\(hyto operation.
.LP
	 A TC\(hyuser may cancel an operation which it has previously invoked. 
No reply for this invocation will be accepted afterwards. 
.LP
	The last component may be:
.LP
	\(em
	a return result indicating success
.LP
	\(em
	a return error indicating operation failure
.LP
	\(em
	a reject indicating a syntax error.
.LP
	b)
	abnormal situations handling
.LP
	The Component sub\(hylayer covers a number of abnormal
situations in relation with a component:
.LP
	\(em
	 component reject: when the Component sub\(hylayer receives a malformed 
component, or a component which violates the rules of exchange of operations 
and replies, it informs the TC\(hyuser(s) 
.LP
	\(em
	 operation expiry: when the Component sub\(hylayer detects that a class\ 
1,\ 2 or\ 3 operation has not received a final reply after some 
amount of time (which depends on the operation), it releases the corresponding 
invoke ID and informs the TC\(hyuser. Note that this situation is abnormal 
only in the case of a class\ 1 operation. Application of this to class\ 
4 operations is a local matter. 
.bp
.sp 1P
.LP
2.3.2.4
	\fIError handling\fR 
.sp 9p
.RT
.PP
When the Component sub\(hylayer is informed of a situation which
prevents it from providing the service expected by the TC\(hyusers, it 
will notify the TC\(hyuser, and may terminate the peding operations. 
.PP
A TC\(hyuser may also decide to abort a dialogue, which puts an end to
any pending operation.
.RT
.sp 1P
.LP
2.3.3
	\fIService provided by the Transaction Sub\(hylayer\fR 
.sp 9p
.RT
.PP
The Transaction sub\(hylayer provides the capability for the exchange of 
components between TR\(hyusers. The transaction sub\(hylayer also provides 
the 
capability to send transaction messages between peer TR\(hylayer entities 
by means of the services provided by the lower layer network services. 
The only foreseen TS\(hyuser for the moment is the component sub\(hylayer. 
Two types of service are 
provided:
.RT
.sp 1P
.LP
2.3.3.1
	\fIUnstructured dialogue\fR 
.sp 9p
.RT
.PP
There is no explicit initiation, or termination associated with an unstructured 
dialogue. The only facility provided to the TC\(hyuser is the 
capability to send one, or several components that do not expect replies
(invocation of class\ 4 operations) grouped in a unidirectional message 
to the remote TR\(hyuser. 
.PP
At the originating side, the TC\(hyuser indicates the components to be
sent in a unidirectional message by means of primitives of the request type
containing a unique dialogue\ ID. When the TC\(hyuser issues a TC\(hyUNI 
request 
primitive with the same dialogue ID, all the components with the same dialogue 
ID are sent as user data to the transaction sub\(hylayer by means of the 
TR\(hyUNI 
primitive by the component sub\(hylayer. At the transaction sub\(hylayer 
message 
level, the unidirectional message does not contain any transaction ID thereby 
providing no association between messages of this type. The dialogue ID 
is used to send a group of components in a UNI message to a particular 
destination 
address.
.RT
.sp 1P
.LP
2.3.3.2
	\fIStructured dialogue\fR 
.sp 9p
.RT
.PP
The structured dialogue facility allows a TC\(hyuser to start a
dialogue, exchange components within this dialogue, terminate it, or abort it.
.PP
Each TR\(hyuser identifies a transaction by a separate transaction ID.
The following facilities are provided:
.RT
.LP
	\(em
	 transaction begin: the beginning of a transaction between two TR\(hyusers 
causes a transaction ID to be allocated to this transaction, and 
permits sending TR\(hyuser information to the destination TR\(hyuser. In 
response to transaction begin, the destination TR\(hyuser may continue 
the transaction, or end it. 
.LP
	\(em
	transaction continuation: allows full\(hyduplex exchange of
messages between TR\(hyusers inside a transaction.
.LP
	\(em
	 transaction end: release the associated transaction ID, and puts an end 
to the exchange of messages inside this transaction. Either of the TR\(hyusers 
may decide to end a transaction. There are three ways for the TR\(hyuser 
to terminate a transaction: 
.LP
	1)
	prearranged end: a convention exists between the
TR\(hyusers; each of them may decide to terminate the transaction without 
having to inform the peer TR\(hyuser, which will take a similar decision 
on its own 
.LP
	2)
	basic end: it informs the peer TR\(hyuser, possibly
sending TR\(hyuser information to it.
.LP
	3)
	transaction abort: causes the abandonment of any
message of the transaction for which transmission or delivery is pending, 
and ends the transaction. The reason for aborting the transaction is indicated 
to the remote TR\(hyuser. 
.LP
	\(em
	 if, for some reason, no response of any kind is received to transaction 
begin, the Transaction sub\(hylayer will eventually abort this 
transaction and inform the TR\(hyuser. This is a local option.
.LP
	\(em
	 transaction abort by TCAP: whenever one of a list of abnormal situations 
is detected, the Transaction sub\(hylayer decides to abort the 
corresponding transaction and informs the TR\(hyusers.
.bp
.LP
	\(em
	 exception reporting: the Transaction sub\(hylayer may report to TR\(hyusers 
abnormal situations of which it is notified by the underlying 
layer.
.PP
When the TR\(hyuser is the Component sub\(hylayer:
.LP
	a)
	there is a one\(hyto\(hyone mapping between a dialogue and a
transaction,
.LP
	b)
	 a message may contain zero, one or more components, within the limits 
of the message size supported by the underlying layer. 
.sp 1P
.LP
2.4
	\fITC Based on a connection\(hyoriented network service\fR 
.sp 9p
.RT
.PP
For further study.
.RT
.LP
\fB3\fR 	\fBService provided by TC based on a connectionless network
service\fR 
.sp 1P
.RT
.sp 2P
.LP
3.1
	\fIComponent Sub\(hylayer\fR 
.sp 1P
.RT
.sp 1P
.LP
3.1.1
	\fIOverview of Component Sub\(hylayer primitives\fR 
.sp 9p
.RT
.PP
Tables 1/Q.771 and 2/Q.771 give an overview of the primitives
to/from the TC\(hyusers, and contain references to the sections of this
Recommendation where these primitives are described in detail.
.PP
Table 1/Q.771 shows the TC\(hyprimitives relating to dialogue handling. 
The purpose of these primitives is to request or indicate facilities of 
the 
underlying (sub)\(hylayer, in relation with message transmission or dialogue
handling. When the Transaction Sub\(hylayer is used to support the dialogue, 
these primitives map onto TR\(hyprimitives with the same 
generic name, as there is a one to one relationship between a dialogue and a
transaction.
.RT
.ce
\fBH.T. [T1.771]\fR 
.ce
TABLE\ 1/Q.771
.ce
\fBPrimitives for dialogue handling\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(156p) | cw(36p) | cw(36p) .
Name	Type	Section
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TC\(hyUNI	Request Indication	3.1.2.2.1
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TC\(hyBEGIN	Request Indication	3.1.2.2.2.1
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TC\(hyCONTINUE	Request Indication	3.1.2.2.2.2
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TC\(hyEND	Request Indication	3.1.2.2.2.3
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TC\(hyU\(hyABORT	Request Indication	3.1.2.2.2.3
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TC\(hyP\(hyABORT	Indication	3.1.4.2
_
.TE
.nr PS 9
.RT
.ad r
\fBTable 1/Q.771 [T1.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.LP
	\(em
	TC\(hyUNI: requests/indicates an unstructured dialogue.
.LP
	\(em
	TC\(hyBEGIN: begins a dialogue.
.LP
	\(em
	TC\(hyCONTINUE: continues a dialogue.
.LP
	\(em
	TC\(hyEND: ends a dialogue.
.bp
.PP
Each of the previous primitives causes any component(s) previously passed 
on the interface for the referenced dialogue to be delivered to the 
remote end (except TC\(hyEND with prearranged end).
.LP
	\(em
	TC\(hyU\(hyABORT: allows a TC\(hyuser to terminate a dialogue
abruptly, without transmitting any pending components.
.LP
	\(em
	TC\(hyP\(hyABORT: informs the TC\(hyuser that the dialogue has been
terminated by the service provider (i.e.\ TC Transaction sub\(hylayer) 
in reaction to a transaction abort by the Transaction sub\(hylayer. Any 
pending components are not transmitted. 
.PP
Table 2/Q.771 shows the TC\(hyprimitives for component handling. The main 
purpose of these primitives is to handle operations and replies; these 
primitives do not as such require facilities from the underlying (sub)\(hylayer. 
.ce
\fBH.T. [T2.771]\fR 
.ce
TABLE\ 2/Q.771
.ce
\fBPrimitives for component handling\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(156p) | cw(36p) | cw(36p) .
Name	Type	Section
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TC\(hyINVOKE	Request Indication	3.1.3.2
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TC\(hyRESULT\(hyL	Request Indication	3.1.3.3
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TC\(hyRESULT\(hyNL	Request Indication	3.1.3.3
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TC\(hyU\(hyERROR	Request Indication	3.1.3.4
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TC\(hyL\(hyCANCEL	Indication	3.1.3.6
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TC\(hyU\(hyCANCEL	Request	3.1.3.6
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TC\(hyL\(hyREJECT	Indication	3.1.4.1
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TC\(hyR\(hyREJECT	Indication	3.1.4.1
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TC\(hyU\(hyREJECT	Request Indication	3.1.3.5
_
.TE
.nr PS 9
.RT
.ad r
\fBTable 2/Q.771 [T2.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.LP
	\(em
	 TC\(hyINVOKE: invocation of an operation, which may be linked to another 
operation invocation 
.LP
	\(em
	 TC\(hyRESULT\(hyL: only result or last part of the segmented result of 
a successfully executed operation 
.LP
	\(em
	TC\(hyRESULT\(hyNL: non\(hyfinal part of the segmented result of a
successfully executed operation
.LP
	\(em
	TC\(hyU\(hyERROR: reply to a previously invoked operation,
indicating that the operation execution failed
.LP
	\(em
	TC\(hyL\(hyCANCEL: informs the TC\(hyuser locally that an operation
invocation is terminated due to a timeout condition
.LP
	\(em
	TC\(hyU\(hyCANCEL: causes local termination of an operation
invocation, as a consequence of a TC\(hyuser decision
.bp
.LP
	\(em
	 TC\(hyL\(hyREJECT: (local reject) informs the local TC\(hyuser that a 
Component sub\(hylayer detected invalid component was received 
.LP
	\(em
	 TC\(hyR\(hyREJECT: (remote reject) indicates that TCAP detected an invalid 
component 
.LP
	\(em
	TC\(hyU\(hyREJECT: rejection of a component by the TC\(hyuser,
indicating a malformation which prevents the operation from being executed, 
or the reply from being understood 
.PP
The various primitives associated with component and dialogue
handling are described with their parameters. The following notation is
used:
.LP
	(M)
	indicates a mandatory parameter
.LP
	(O)
	indicates an optional parameter
.LP
	FS
	indicates that further study is required
.LP
	A blank indicates that the parameter is not applicable
.LP
	(=)
	 indicates that the parameter must have the same value in a request primitive 
and in the corresponding indication primitive. 
.PP
This notation applies throughout this Recommendation.
.sp 1P
.LP
3.1.2
	\fIDialogue Handling\fR 
.sp 9p
.RT
.PP
Dialogue handling provides facilities for the exchange of
components within a dialogue.
.RT
.sp 1P
.LP
3.1.2.1
	\fIDefinition of Parameters\fR 
.sp 9p
.RT
.PP
This section defines the parameters used with the primitives
associated with dialogue handling.
.PP
Address parameters: two address parameters are used: the \*QDestination 
Address\*U and the \*QOriginating Address\*U parameters. These parameters 
identify 
respectively the destination and originating TC\(hyuser.
.PP
\*QComponents Present\*U: indicates whether any components will be
received; when no component is being transmitted, it indicates that the 
list is empty, other wise it indicates a sequence (see\ \(sc\ 3.1.3.8) 
of components which are associated with the dialogue handling primitive. 
The \*QComponents Present\*U parameter is used in primitives of the indication 
type only. 
.PP
\*QDialogue ID\*U: this parameter also appears in the component handling 
primitives, and is used to associate components with a dialogue. The same 
dialogue ID must be used within the same dialogue, or a unidirectional
primitive.
In a unidirectional primitive the same dialogue ID assures all components 
with the identical dialogue ID are blocked together in the same unidirectional 
message destined for the same destination address. For structured dialogues,
the dialogue ID is used to identify all the components belonging to the same
dialogue from the beginning of the dialogue to its end. The dialogue ID maps
onto the IDs exchanged in the messages between a pair of nodes.
.PP
\*QP\(hyABORT\*U: contains information indicating the cause for which TCAP
decides to abort a dialogue.
.PP
\*QParameters\*U: contains the parameter(s) to be sent to the remote
TC\(hyuser in association with an operation invocation, a reply, or a dialogue
abort. This information is not analysed by TCAP.
.PP
\*QQuality of Service\*U: the TC\(hyuser indicates the acceptable quality 
of service. The default value of this parameter corresponds to the underlying 
service defined in\ \(sc\ 3.4. Other Quality of service is for further study.
.PP
\*QTermination\*U: indicates which scenario is chosen by the TC\(hyuser 
for the end of the dialogue (prearranged or basic). 
.PP
\*QUser Abort Information\*U: the TC\(hyuser may include information related 
to a TC\(hyuser\(hyinitiated abort. 
.RT
.sp 1P
.LP
3.1.2.2
	\fIDialogue facilities\fR 
.sp 9p
.RT
.PP
The dialogue facilities allow a TC\(hyuser to exchange components with 
a peer TC\(hyuser to perform a distributed application. The unidirectional 
message facility may be used to send class\ 4 operation invocations and 
reports of 
protocol errors in these invocations from either TC\(hyuser using an unstructured 
dialogue. The structured dialogue facilities provide the capability to 
explicitly initiate a transaction, exchange components within the dialogue,
terminate it, or abort it.
.bp
.RT
.sp 1P
.LP
3.1.2.2.1\ \ 
\fIUnstructured dialogue\fR 
.sp 9p
.RT
.PP
There is no initiation or termination associated with an
unstructured dialogue; the only facility provided is the request for
transmission of one, or several components invoking class\ 4 operations or
reporting protocol errors in these invocations, grouped in a message to the
remote TC\(hyuser.
.PP
Components to be transmitted have been previously passed to the
component sub\(hylayer by means of component handling primitives of the 
\*Qrequest\*U type. 
.PP
The use of the unstructured dialogue facility is indicated by issuing  a 
TC\(hyUNI
primitive, as described in Table\ 3/Q.771.
.PP
At the originating side, a TC\(hyUNI request primitive is issued to
request transmission to the remote TC\(hyuser of all the components which have
been passed to the component sub\(hylayer with the same dialogue\ ID.
.PP
At the receiving side, the destination TC\(hyuser is informed that one 
or more component(s) have been received by means of a TC\(hyUNI indication 
primitive. The parameters in this primitive apply to all the components 
being received; 
these components will actually be delivered by means of component handling
primitives of the indication type.
.RT
.ce
\fBH.T. [T3.771]\fR 
.ce
TABLE\ 3/Q.771
.ce
\fBTC\(hyUNI Primitives\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(108p) | cw(60p) sw(60p) , ^  | c | c.
Parameter	Primitive: TC\(hyUNI
	Request	Indication
_
.T&
lw(108p) | cw(60p) | lw(60p) .
Quality of service	FS	
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Destination address	M	M | ua\d\u)\d
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Originating address	M | ua\d\u)\d	M (=)
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Dialogue ID	M | ub\d\u)\d	
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Components present	M	M (=)
.TE
.LP
\ua\d\u)\d
This parameter may be implicitly associated with the access
point at which the primitive is issued.
.LP
\ub\d\u)\d
This parameter has only local significance.
.nr PS 9
.RT
.ad r
\fBTable 3/Q.771 [T3.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.sp 1P
.LP
3.1.2.2.2\ \ 
\fIStructured dialogue\fR 
.sp 9p
.RT
.PP
The structured dialogue facility allows a TC\(hyuser to start a
dialogue, exchange components within this dialogue, terminate it, or abort 
it. It provides for Transaction IDs in the transaction messages that provide 
a 
unique association among the related transaction messages.
.RT
.sp 1P
.LP
3.1.2.2.2.1\ \ 
\fIBeginning of a dialogue\fR 
.sp 9p
.RT
.PP
A TC\(hyuser begins a new dialogue by issuing a TC\(hyBEGIN request
primitive. The purpose of this primitive is:
.RT
.LP
	\(em
	to indicate to the Component sub\(hylayer that a new dialogue
starts, identified by the Dialogue ID parameter of the primitive;
.LP
	\(em
	 to request transmission of any component(s) previously passed to the 
Component sub\(hylayer by means of component handling primitives of the 
\*Qrequest\*U type with the same Dialogue\ ID.
.bp
.PP
A TC\(hyBEGIN request primitive may be issued prior to passing any
component to the Component sub\(hylayer.
.PP
At the receiving side, the destination TC\(hyuser is informed that a new 
dialogue starts by means of a TC\(hyBEGIN indication primitive. The presence 
of 
component(s) is indicated by the Components Present.
.PP
Table 4/Q.771 describes the 
TC\(hyBEGIN
primitives.
.RT
.LP
.sp 2
.ce
\fBH.T. [T4.771]\fR 
.ce
TABLE\ 4/Q.771
.ce
\fBTC\(hyBEGIN Primitives\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(108p) | cw(60p) sw(60p) , ^  | c | c.
Parameter	Primitive: TC\(hyBEGIN
	Request	Indication
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Quality of service	FS	FS
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Destination address	M	M | ua\d\u)\d
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Originating address	M | ua\d\u)\d	M (=)
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Dialogue ID	M	M
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Components present		M
.TE
.LP
\ua\d\u)\d
This parameter may be implicitly associated with the access
point at which the primitive is issued.
.nr PS 9
.RT
.ad r
\fBTable 4/Q.771 [T4.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.LP
.sp 2
.sp 1P
.LP
3.1.2.2.2.2\ \ 
\fIDialogue continuation\fR 
.sp 9p
.RT
.PP
A TC\(hyuser indicates that it wants to continue a dialogue by issuing 
a TC\(hyCONTINUE request primitive. This primitive requests transmission 
of any 
component(s) that have been passed to the Component sub\(hylayer for this
dialogue, since the last TC\(hyBEGIN or TC\(hyCONTINUE request primitive 
was issued for this dialogue. 
.PP
At the receiving side, the TC\(hyCONTINUE indication primitive
indicates:
.RT
.LP
	\(em
	that the dialogue may continue
.LP
	\(em
	that components are being delivered (if the Components
Present parameter does not indicate \*Qempty\*U).
.bp
.PP
Table 5/Q.771 describes the 
TC\(hyCONTINUE
primitives.
.ce
\fBH.T. [T5.771]\fR 
.ce
TABLE\ 5/Q.771
.ce
\fBTC\(hyCONTINUE Primitives\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(108p) | cw(60p) sw(60p) , ^  | c | c.
Parameter	Primitive: TC\(hyCONTINUE
	Request	Indication
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Dialogue ID	M	M
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Components present		M
_
.TE
.nr PS 9
.RT
.ad r
\fBTable 5/Q.771 [T5.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.sp 1P
.LP
3.1.2.2.2.3\ \ 
\fIEnd of a dialogue\fR 
.sp 9p
.RT
.PP
Three scenarios are provided to TC\(hyusers to end a
dialogue:
.RT
.LP
	\(em
	prearranged end
.LP
	\(em
	basic end
.LP
	\(em
	abort by the TC\(hyuser.
.PP
Dialogue ending uses the 
TC\(hyEND
request and indication
primitives described in Table\ 6/Q.771. The TC\(hyEND request primitive 
indicates which scenario is being used for the dialogue. 
.ce
\fBH.T. [T6.771]\fR 
.ce
TABLE\ 6/Q.771
.ce
\fBTC\(hyEND Primitives\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(108p) | cw(60p) sw(60p) , ^  | c | c.
Parameter	Primitive: TC\(hyEND
	Request	Indication
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Dialogue ID	M	M
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Components present		M
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Termination	M	
_
.TE
.nr PS 9
.RT
.ad r
\fBTable 6/Q.771 [T6.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.LP
	a)
	prearranged end
.LP
	In this scenario, TC\(hyusers have decided by prior
arrangement when to end the dialogue: the effect of the TC\(hyEND primitive is
purely local; no TC\(hyEND indication is used.
.LP
	 No component can be sent or received for the dialogue once the TC\(hyEND 
request primitive has been issued. 
.bp
.LP
	b)
	basic end
.LP
	In this scenario, the ending causes transmission of any
pending components at the side which initiates it. Note, however, that any
components for which transmission would be pending in the reverse direction
will not be delivered.
.LP
	The basic scenario uses the TC\(hyEND primitives for two purposes:
.LP
	\(em
	delivery of any component(s) that has been passed to
the Transaction sub\(hylayer, and for which transmission is pending
.LP
	\(em
	indication that no more components will be exchanged
for this dialogue in either direction.
.LP
	c)
	abort of a dialogue by a TC\(hyuser
.LP
	 The TC\(hyuser has the ability to request immediate ending of a dialogue 
without taking into account any pending operation invocation (abort). When 
doing so, the TC\(hyuser may provide end to end information indicating 
the 
cause of the abort and diagnostic information; this information is transported 
by TCAP without analysis. 
.PP
The 
TC\(hyU\(hyABORT
request and indication primitives are used to indicate abort by the TC\(hyuser; 
Table\ 7/Q.771 describes these primitives. 
.ce
\fBH.T. [T7.771]\fR 
.ce
TABLE\ 7/Q.771
.ce
\fBTC\(hyU\(hyABORT Primitives 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(108p) | cw(60p) sw(60p) , ^  | c | c.
Parameter	Primitive: TC\(hyU\(hyABORT
	Request	Indication
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Dialogue ID	M	M
_
.T&
lw(108p) | cw(60p) | cw(60p) .
User abort information	O	O (=)
_
.TE
.nr PS 9
.RT
.ad r
\fBTable 7/Q.771 [T7.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.sp 2P
.LP
3.1.3
	\fIComponent Handling\fR 
.sp 1P
.RT
.sp 1P
.LP
3.1.3.1
	\fIDefinition of Parameters\fR 
.sp 9p
.RT
.PP
This section defines the parameters used with the primitives
associated with component handling.
.PP
\*QClass\*U: see \(sc 2.3.2.3.
.PP
\*QDialogue ID\*U: relates components to a specific dialogue.
.PP
\*QInvoke ID\*U: identifies an operation invocation.
.PP
\*QLinked ID\*U: links an operation invocation to a previous operation
invocation.
.PP
\*QError\*U: contains information provided by the TC\(hyuser when an
operation returns failure. This information is not analysed by TCAP.
.PP
\*QLast Component\*U: is used in primitives of the \*Qindication\*U type 
only, to designate the last component of a message. Note that indication 
of the last part of the result of an operation is via the name of the primitive. 
.PP
\*QOperation\*U: identifies the action to be executed by a TC\(hyuser on
request of another TC\(hyuser.
.PP
\*QParameters\*U: contains any parameters accompanying an operation, or
provided in reply to an operation.
.PP
\*QProblem Code\*U: identifies the cause for rejecting a component.
.PP
\*QTimeout\*U: indicates the maximum lifetime of a component ID. It is
used to handle cases where operations do not receive any expected reply.
.bp
.RT
.sp 1P
.LP
3.1.3.2
	\fIOperation Invocation\fR 
.sp 9p
.RT
.PP
An operation invocation is requested to the Component sub\(hylayer by means 
of a TC\(hyINVOKE request primitive. When this invocation is linked to 
a 
previous operation, the Linked ID parameter is used.
.PP
A corresponding 
TC\(hyINVOKE
indication primitive is used to
indicate operation activation to the destination TC\(hyuser.
.PP
Table 8/Q.771 shows the primitives associated with operation
invocation.
.RT
.ce
\fBH.T. [T8.771]\fR 
.ce
TABLE\ 8/Q.771
.ce
\fBOperation invocation primitives\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(108p) | cw(60p) sw(60p) , ^  | c | c.
Parameter	Primitive: TC\(hyINVOKE
	Request	Indication
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Dialogue ID	M	M | ua\d\u)\d
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Class	M	
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Invoke ID	M	M (=)
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Linked ID	O	O (=)
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Operation	M	M (=)
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Parameters	O	O (=)
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Last component		M
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Timeout	M
.TE
.LP
\ua\d\u)\d
Mandatory except for invocation of class 4 operation received
in a unidirectional message.
.nr PS 9
.RT
.ad r
\fBTable 8/Q.771 [T8.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.sp 1P
.LP
3.1.3.3
	\fIReport of success\fR 
.sp 9p
.RT
.PP
Success is reported to indicate that an operation (of class\ 1 or\ 3) has 
been executed by the remote TC\(hyuser. The operation is identified in 
the 
Invoke ID parameter. Several replies may be used to report success.
The following primitives are used:
.RT
.LP
	\(em
	TC\(hyRESULT\(hyL indicates the only or last segment of a result
.LP
	\(em
	TC\(hyRESULT\(hyNL indicates a segment of a result (with more
segments to follow)
.PP
There is no limitation on the number of segments.
.PP
The 
TC\(hyRESULT\(hyL
and 
TC\(hyRESULT\(hyNL
primitives are
described in Table\ 9/Q.771. A primitive of the \*Qrequest\*U type is used 
to pass a result from the TC\(hyuser to the Component sub\(hylayer; a primitive 
of the 
\*Qindication\*U type is used to deliver this result to the TC\(hyuser.
.bp
.RT
.ce
\fBH.T. [T9.771]\fR 
.ce
TABLE\ 9/Q.771
.ce
\fBReport of success primitives\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(60p) | cw(84p) sw(84p) , ^  | c | c.
Parameter	Primitive
	 {
TC\(hyRESULT\(hyL
TC\(hyRESULT\(hyNL
Request
 }	 {
TC\(hyRESULT\(hyL
TC\(hyRESULT\(hyNL
Indication
 }
_
.T&
lw(60p) | cw(84p) | cw(84p) .
Dialogue ID	M	M
_
.T&
lw(60p) | cw(84p) | cw(84p) .
Invoke ID	M	M (=)
_
.T&
lw(60p) | cw(84p) | cw(84p) .
Parameters	O	O (=)
_
.T&
lw(60p) | cw(84p) | cw(84p) .
Last component		M
_
.TE
.nr PS 9
.RT
.ad r
\fBTable 9/Q.771 [T9.772], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.sp 1P
.LP
3.1.3.4
	\fIReport of failure\fR 
.sp 9p
.RT
.PP
A TC\(hyuser receiving a (class\ 1 or\ 2) operation which it cannot
execute, though it \*Qunderstands\*U it, will issue a TC\(hyU\(hyERROR 
request primitive, indicating the reason of the failure (Error parameter). 
The corresponding 
operation is identified by the Invoke ID parameter.
.PP
The TC\(hyuser which invoked this operation is informed by a
TC\(hyU\(hyERROR
indication primitive.
.PP
Table 10/Q.771 describes the TC\(hyU\(hyERROR primitives.
.RT
.ce
\fBH.T. [T10.771]\fR 
.ce
TABLE\ 10/Q.771
.ce
\fBReport of failure primitives\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(108p) | cw(60p) sw(60p) , ^  | c | c.
Parameter	Primitive: TC\(hyU\(hyERROR
	Request	Indication
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Dialogue ID	M	M
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Invoke ID	M	M (=)
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Error	M	M (=)
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Parameters	O	O (=)
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Last component		M
.TE
.LP
\fINote\fR
\ \(em\ Report of failure is a final reply.
.nr PS 9
.RT
.ad r
\fBTable 10/Q.771 [T10.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.sp 1P
.LP
3.1.3.5
	\fIReject by the TC\(hyUser\fR 
.sp 9p
.RT
.PP
A TC\(hyuser may reject any component (except a reject component)
generated by its peer entity, which it considers incorrect. The cause for 
the rejection is indicated in the Problem Code parameter; separate parameters 
are available for the rejection of individual component types. 
.PP
Any rejection of an invocation or a result terminates the operation. When 
a linked operation is rejected, the linked\(hyto operation is not affected. 
.PP
A TC\(hyuser rejects a component by means of the 
TC\(hyU\(hyREJECT
request primitive, and is informed of rejection by the remote TC\(hyuser 
by means of the TC\(hyU\(hyREJECT indication primitive. These primitives 
are described by 
Table\ 11/Q.771.
.RT
.LP
.sp 2
.ce
\fBH.T. [T11.771]\fR 
.ce
TABLEAU\ 11/Q.771
.ce
\fBUser rejection primitives\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(108p) | cw(60p) sw(60p) , ^  | c | c.
Parameter	Primitive: TC\(hyU\(hyREJECT
	Request	Indication
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Dialogue ID	M	M | ua\d\u)\d
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Invoke ID	M	M (=)
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Problem code	M	M (=)
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Last component		M
.TE
.LP
\ua\d\u)\d
Mandatory except for rejection of invocation of class 4 operation received in a unidirectional message.
.nr PS 9
.RT
.ad r
\fBTable 11/Q.771 [T11.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.LP
.sp 2
.sp 1P
.LP
3.1.3.6
	\fICancel of an Operation\fR 
.sp 9p
.RT
.PP
The cancel facility terminates the corresponding operation
invocation. It can be requested either by the TC\(hyuser, or by the Component
sub\(hylayer. In both cases, it has only local effect: no notification 
is sent to the remote end. 
.PP
The Component sub\(hylayer uses the cancel facility to inform the TC\(hyuser 
that the timer associated with a class\ 1,\ 2 or\ 3 operation has expired; 
the 
TC\(hyL\(hyCANCEL
indication primitive is used for this purpose. The timer is run for all 
classes, but the reporting for class\ 4 operations is a local 
matter.
.PP
The TC\(hyuser uses the 
TC\(hyU\(hyCANCEL
request primitive to inform the local Component sub\(hylayer of a cancel 
decision. No component is 
sent.
.bp
.PP
Table 12/Q.771 describes the TC\(hyCANCEL primitives.
.RT
.ce
\fBH.T. [T12.771]\fR 
.ce
TABLE\ 12/Q.771
.ce
\fBTC\(hyCANCEL Primitives\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(60p) | cw(84p) sw(84p) , ^  | c | c.
Parameter	Primitive
	TC\(hyL\(hyCANCEL indication	TC\(hyU\(hyCANCEL request
_
.T&
lw(60p) | cw(84p) | cw(84p) .
Dialogue ID	M	M
_
.T&
lw(60p) | cw(84p) | cw(84p) .
Invoke ID	M	M
_
.TE
.nr PS 9
.RT
.ad r
\fBTable 12/Q.771 [T12.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.sp 1P
.LP
3.1.3.7
	\fIGrouping of Components inside a Message\fR 
.sp 9p
.RT
.PP
A sequence of components is obtained by passing one or several
components with a given Dialogue ID to the Component Sub\(hylayer between two
successive requests for transmission (TC\(hyBEGIN, TC\(hyCONTINUE or TC\(hyEND 
request primitives), or before the first one (TC\(hyBEGIN request), using 
the same 
Dialogue ID, or the only request for transmission (i.e.\ TC\(emUNI).
.PP
At the originating side, a list of components is delimited by TC\(hyUNI, 
TC\(hyBEGIN, TC\(hyCONTINUE or TC\(hyEND request primitives. 
.PP
At the destination side, a sequence of components starts with a
primitive indicating transmission; its end is indicated by the \*QLast 
Component\*U parameter of the primitives which deliver components to a 
TC\(hyuser. The 
\*QComponents Present\*U parameter in the transmission primitive indicates 
whether the sequence is empty, or not. 
.PP
\fINote\fR \ \(em\ Components grouped inside a message are delivered to the
remote end in the same order as they are provided by the TC\(hyuser at the
originating end.
.RT
.sp 2P
.LP
3.1.4
	\fIAbnormal situations\fR 
.sp 1P
.RT
.sp 1P
.LP
3.1.4.1
	\fIReject of a Component by the Component sub\(hylayer\fR 
.sp 9p
.RT
.PP
When detecting that a received component is invalid, the Component sub\(hylayer 
notifies the local TC\(hyuser by means of the 
TC\(hyL\(hyREJECT
indication primitive. This primitive indicates the cause of the reject 
(Problem Code parameter) with sufficient information to make the retention 
of the failed component superfluous: whenever possible the Component Type 
and Component ID 
are indicated; otherwise a \*Qgeneral problem\*U cause is indicated. This
information is passed to the TC\(hyuser, and also retained in the Component
sub\(hylayer which uses it to form a reject component.
.PP
Any type of component can be rejected. When the component to be
rejected is itself identified as a reject component, rejection is purely 
local; when the rejected component is identified as an invoke or a result, 
the whole corresponding operation is considered as terminated; when it 
is a linked 
operation, this linked operation is terminated, but the linked\(hyto operation 
is not affected. 
.PP
When informed of a Component sub\(hylayer reject, the local TC\(hyuser 
may decide to continue the exchange of components. If so, the remote TC\(hyuser 
is 
informed through the reject component sent when the local TC\(hyuser issues the
next dialogue handling primitive.
.PP
If the Component sub\(hylayer generated reject combined with accumulated 
components from the TC\(hyuser exceeds the message length limitations, 
then the 
TC\(hyuser, being aware of the reject component, must initiate two dialogue
handling primitives. The Component sub\(hylayer, also being aware of the length
problem, will send all the components, except the reject, with the first
primitive. The reject will be sent with the next dialogue handling primitive
together with any further components provided by the TC\(hyuser.
.bp
.PP
Table 13/Q.771 describes the primitives used in relation with TCAP
component rejection.
.RT
.ce
\fBH.T. [T13.771]\fR 
.ce
TABLE\ 13/Q.771
.ce
\fBComponent sub\(hylayer rejection primitive 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(60p) | cw(84p) sw(84p) , ^  | c | c.
Parameter	Primitive
	TC\(hyL\(hyREJECT indication	TC\(hyR\(hyREJECT indication
_
.T&
lw(60p) | cw(84p) | cw(84p) .
Dialogue ID	M	M | ua\d\u)\d
_
.T&
lw(60p) | cw(84p) | cw(84p) .
Invoke ID	O	O
_
.T&
lw(60p) | cw(84p) | cw(84p) .
Problem code	M	M
_
.T&
lw(60p) | cw(84p) | cw(84p) .
Last component		M
.TE
.LP
\ua\d\u)\d
Mandatory except for rejection of invocation of a class 4
operation received in a unidirectional message.
.nr PS 9
.RT
.ad r
\fBTable 13/Q.771 [T13.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.sp 1P
.LP
3.1.4.2
	\fIDialogue abort\fR 
.sp 9p
.RT
.PP
Due to an abnormal situation, an underlying (sub\(hy)layer may decide to 
abort the association between users; the dialogue has then to be aborted. 
All associated operations are terminated, and the TC\(hyusers are notified by
means of 
TC\(hyP\(hyABORT
indication primitives. The P\(hyabort parameter
contains the cause for which it was decided to abort the dialogue.
.PP
The Component sub\(hylayer does not decide on dialogue abort.
.PP
Table 14/Q.771 describes the TC\(hyP\(hyABORT primitive.
.RT
.ce
\fBH.T. [T14.771]\fR 
.ce
TABLE\ 14/Q.771
.ce
\fBPrimitive for TCAP Abort\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(84p) | cw(96p) , ^  | c.
Parameter	Primitive
	TC\(hyP\(hyABORT indication
_
.T&
lw(84p) | cw(96p) .
Dialogue ID	M
_
.T&
lw(84p) | cw(96p) .
P\(hyabort	M
_
.TE
.nr PS 9
.RT
.ad r
\fBTable 14/Q.771 [T14.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.sp 1P
.LP
3.1.5
	\fIComponent states and state transition diagrams\fR 
.sp 9p
.RT
.PP
For a given component ID, component correlation takes place only at the 
side which originates the operation; for this ID, component states and 
state transition diagrams are defined at this side only. The other side just
reflects the value of the component ID in an Invoke or a Linked\ ID.
.bp
.PP
The following states are defined:
.RT
.LP
	\(em
	Idle: no activity associated with the component ID
.LP
	\(em
	Operation Pending: an operation has been passed to the
Component sub\(hylayer, but no request for transmission has been issued
.LP
	\(em
	Operation Sent: an operation has been transmitted to the
remote end, but no result has been received
.LP
	\(em
	Wait for Reject: the result has been received; TCAP is
waiting for its possible rejection by the TC\(hyuser
.LP
	\(em
	Reject pending: reject of the result has been requested by
the TC\(hyuser, but no request for transmission has been issued.
.PP
State transition diagrams are defined for the four classes of
operations.
.PP
\fINote\ 1\fR \ \(em\ Each of these diagrams corresponds to one component ID:
the one indicated in the Invoke ID parameter; linked operations do not alter
the state machine of the linked\(hyto operation.
.PP
\fINote\ 2\fR \ \(em\ TC\(hyEND request or indication primitives, TC\(hyU\(hyABORT 
request or indication primitives, or the TC\(hyP\(hyABORT indication primitive 
cause return to the \*QIdle\*U state of any component ID associated with 
the dialogue. 
Corresponding transitions are not represented on the diagrams.
.RT
.LP
.rs
.sp 33P
.ad r
\fBFigure 5/Q.771, p.18\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.LP
.rs
.sp 47P
.ad r
\fBFigure 6/Q.771, p.19\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.LP
.rs
.sp 47P
.ad r
\fBFigure 7/Q.771, p.20\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.LP
.rs
.sp 47P
.ad r
\fBFigure 8/Q.771, p.21\fR 
.sp 1P
.RT
.ad b
.RT
.LP
.bp
.sp 1P
.LP
3.1.6
	\fIMapping of Component sub\(hylayer onto Transaction sub\(hylayer\fR 
.sp 9p
.RT
.PP
When mapping the Component sub\(hylayer onto the Transaction
sub\(hylayer, a one to one mapping exists between a dialogue and a transaction
explicity in the case of a structured dialogue, or implicitly in the case 
of an unstructured dialogue. It follows that there is a one to one relationship 
between dialogue handling primitives of the Component sub\(hylayer and 
transaction handling primitives in the Transaction sub\(hylayer; similar 
generic names have 
been chosen for the primitives to reflect this. The component handling
primitives of the Component sub\(hylayer have no counterpart in the Transaction
sub\(hylayer.
.PP
The correspondence between the two sub\(hylayers is further described in 
Recommendation\ Q.774. 
.RT
.sp 2P
.LP
3.2
	\fITransaction Sub\(hylayer\fR 
.sp 1P
.RT
.sp 1P
.LP
3.2.1
	\fIOverview of\fR 
\fITransaction Sub\(hylayer primitives\fR 
.sp 9p
.RT
.PP
Table 15/Q.771 gives an overview of the primitives between the TR users 
and the Transaction sub\(hylayer. A detailed description of these primitives 
and their parameters is given in the next sections. For each primitive, 
Table\ 15/Q.771 indicates the relevant section.
.RT
.ce
\fBH.T. [T15.771]\fR 
.ce
TABLE\ 15/Q.771
.ce
\fBPrimitives for the transaction sub\(hylayer\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(156p) | cw(36p) | cw(36p) .
Name	Type	Section
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TR\(hyUNI	Request indication	3.2.2
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TR\(hyBEGIN	Request indication	3.2.3
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TR\(hyCONTINUE	Request indication	3.2.4
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TR\(hyEND	Request indication	3.2.5
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TR\(hyU\(hyABORT	Request indication	3.2.5.3
_
.T&
lw(156p) | lw(36p) | lw(36p) .
TR\(hyP\(hyABORT	Indication	3.2.6.1
_
.TE
.nr PS 9
.RT
.ad r
\fBTable 15/Q.771 [T15.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.sp 1P
.LP
	\fIDefinition of the parameters\fR :
.sp 9p
.RT
.PP
\*QQuality of Service\*U: the TR\(hyuser indicates the preferred quality 
of service. This is for further study. 
.PP
\*QDestination Address\*U: identifies the destination TR\(hyuser.
.PP
\*QOriginating Address\*U: identifies the originating TR\(hyuser.
.PP
\*QP\(hyabort\*U: indicates the cause of the abort of a transaction
by\ TCAP.
.PP
\*QReason\*U: indicates the nature of an abnormal situation.
.bp
.PP
\*QTransaction ID\*U: a transaction is identified by a separate
transaction ID at each end.
.PP
\*QTermination\*U: identifies the termination scenario chosen for the
transaction (prearranged or basic).
.PP
\*QUser Abort Information\*U: information related to a TR\(hyuser abort.
.PP
\*QUser Data\*U: contains the information to be passed between
TR\(hyusers.
.RT
.sp 1P
.LP
3.2.2
	\fIInformation Transfer In Unstructured Dialogue\fR 
.sp 9p
.RT
.PP
Information may be sent from one TR\(emuser to another TR\(hyuser without 
establishing an explicit association. In this case, the transaction sub\(hylayer 
considers that there is no relationship among messages transmitted by this 
means.
.PP
The corresponding primitives are the 
TR\(hyUNI
request and
indication primitives, described in Table\ 16/Q.771.
.RT
.LP
.sp 2
.ce
\fBH.T. [T16.771]\fR 
.ce
TABLE\ 16/Q.771
.ce
\fBTR\(hyUNI Primitives\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(108p) | cw(60p) sw(60p) , ^  | c | c.
Parameter	Primitive: TR\(hyUNI
	Request	Indication
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Quality of service	FS	\(em
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Destination address	M	M | ua\d\u)\d
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Originating address	M | ua\d\u)\d	M (=)
_
.T&
lw(108p) | cw(60p) | cw(60p) .
User data	M	M (=)
.TE
.LP
\ua\d\u)\d
This parameter may be implicitly associated with the access
point at which the primitive is issued.
.nr PS 9
.RT
.ad r
\fBTable 16/Q.771 [T16.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.LP
.sp 2
.sp 1P
.LP
3.2.3
	\fITransaction begin\fR 
.sp 9p
.RT
.PP
The transaction begin facility starts a transaction between two
TR\(hyusers. This may be accompanied by the transfer of TR\(hyuser information
(called user data in the following).
.PP
In order to begin a transaction, a TR\(hyuser issues the TR\(hyBEGIN request 
primitive. 
.PP
At the destination side, the TR\(hyBEGIN indication primitive is used to 
inform the destination TR\(hyuser of the beginning of a transaction, and 
to 
deliver any accompanying user data.
.PP
Table 17/Q.771 describes the transaction begin
primitives.
.bp
.RT
.ce
\fBH.T. [T17.771]\fR 
.ce
TABLE\ 17/Q.771
.ce
\fBPrimitives for transaction begin\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(108p) | cw(60p) sw(60p) , ^  | c | c.
Parameter	Primitive: TR\(hyBEGIN
	Request	Indication
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Quality of service	FS	FS
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Destination address	M	M | ua\d\u)\d
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Originating address	M | ua\d\u)\d	M (=)
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Transaction ID	M	M
_
.T&
lw(108p) | cw(60p) | cw(60p) .
User data	O	O (=)
.TE
.LP
\ua\d\u)\d
This parameter may be implicitly associated with the access
point at which the primitive is issued.
.nr PS 9
.RT
.ad r
\fBTable 17/Q.771 [T17.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.PP
Figure 9/Q.771 shows the transaction state transitions during
transaction begin. The following states are introduced:
.LP
	\(em
	Idle (I): the transaction does not exist
.LP
	\(em
	Init Sent (IS): the transaction just started at the
originating side
.LP
	\(em
	Init Received (IR): the transaction just started at the
destination side.
.LP
.rs
.sp 7P
.ad r
\fBFigure 9/Q.771 [T18.771], p.\ (traiter comme tableau MEP)\fR 
.sp 1P
.RT
.ad b
.RT
.sp 1P
.LP
3.2.4
	\fITransaction continuation\fR 
.sp 9p
.RT
.PP
Transaction continuation allows two TR\(hyusers to exchange messages in 
both directions inside a transaction. The TR\(hyCONTINUE primitives are 
used 
for this purpose. They are described by Table\ 18/Q.771.
.PP
The Transaction sub\(hylayer does not provide segmentation/reassembly or 
flow control. 
.PP
State transitions associated with the continuation of a transaction
are represented on Figure\ 10/Q.771, where state\ A (Active) indicates 
that the transaction was accepted by the remote end, and the transaction 
can be used to exchange messages in both directions. 
.bp
.RT
.ce
\fBH.T. [T19.771]\fR 
.ce
TABLE\ 18/Q.771
.ce
\fBTransaction Continuation Primitives\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(108p) | cw(60p) sw(60p) , ^  | c | c.
Parameter	Primitive: TR\(hyCONTINUE
	Request	Indication
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Transaction ID	M	M
_
.T&
lw(108p) | cw(60p) | cw(60p) .
User Data	O	O (=)
_
.TE
.nr PS 9
.RT
.ad r
\fBTable 18/Q.771 [T19.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.LP
.sp 2
.rs
.sp 12P
.ad r
\fBFigure 10/Q.771, p.  \fR 
.sp 1P
.RT
.ad b
.RT
.sp 1P
.LP
3.2.5
	\fITransaction End\fR 
.sp 9p
.RT
.PP
Three facilities are provided to a TR\(hyuser to end a
transaction:
.RT
.LP
	\(em
	prearranged end
.LP
	\(em
	basic end
.LP
	\(em
	abort.
.PP
The first two facilities use the 
TR\(hyEND
primitives; the
Termination parameter indicates which option is selected. The TR\(hyEND 
primitives are described by Table\ 19/Q.771. 
.PP
The last facility uses the TR\(hyU\(hyABORT primitives described by
Table\ 20/Q.771.
.bp
.RT
.ce
\fBH.T. [T20.771]\fR 
.ce
TABLE\ 19/Q.771
.ce
\fBTR\(hyEND primitives\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(108p) | cw(60p) sw(60p) , ^  | c | c.
Parameter	Primitive: TR\(hyEND
	Request	Indication
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Transaction ID	M	M
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Termination	M	
_
.T&
lw(108p) | cw(60p) | cw(60p) .
User data	O	O (=)
_
.TE
.nr PS 9
.RT
.ad r
\fBTable 19/Q.771 [T20.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.sp 1P
.LP
3.2.5.1
	\fIPrearranged end\fR 
.sp 9p
.RT
.PP
When prearranged end has been selected, the procedure is purely
local. Each TR\(hyuser may decide to end the transaction at any point in time,
regardless of the current transaction state. The TR\(hyEND request primitive 
only is used: the remote TR\(hyuser is not informed, and should request 
transaction end on its own. 
.PP
The User Data parameter should not be present in this case.
.PP
Figure 11/Q.771 shows the transaction state transitions for
prearranged end of a transaction. The states are those defined in\ 3.2.3
and\ 3.2.4 above.
.RT
.LP
.rs
.sp 11P
.ad r
\fBFigure 11/Q.771, p.  \fR 
.sp 1P
.RT
.ad b
.RT
.sp 1P
.LP
3.2.5.2
	\fIBasic end\fR 
.sp 9p
.RT
.PP
When basic termination has been selected, the TR\(hyuser requests the end 
of the transaction by issuing the TR\(hyEND request primitive indicating 
this option; the primitive may then contain User Data which is sent to 
the peer 
entity.
.PP
At the destination side, the TR\(hyEND indication primitive is used to
inform the TR\(hyuser of the end of the transaction, and deliver any accompanying 
User Data. 
.PP
Figure 12/Q.771 shows the transaction state transitions for the basic end 
of transaction. The states are those defined in\ \(sc\(sc\ 3.2.3 and\ 3.2.4 
above.
.bp
.RT
.LP
.rs
.sp 11P
.ad r
\fBFigure 12/Q.771, p.  \fR 
.sp 1P
.RT
.ad b
.RT
.sp 1P
.LP
3.2.5.3
	\fITransaction Abort by the TR\(hyuser\fR 
.sp 9p
.RT
.PP
A TR\(hyuser may request the abort of a transaction at any moment; it uses 
for this purpose the 
TR\(hyU\(hyABORT
request primitive, which may
optionally contain the cause of the abort, and/or additional end to end
information. This information is contained in the User Abort Information
parameter: it is transmitted without analysis to the peer entity. Any messages 
of the transaction for which transmission is pending are discarded. 
.PP
A TR\(hyuser is informed of the decision of its peer entity to abort the 
transaction by means of the TR\(hyU\(hyABORT indication primitive. 
.PP
TR\(hyU\(hyABORT
primitives are described by Table\ 20/Q.771.
.RT
.ce
\fBH.T. [T21.771]\fR 
.ce
TABLE\ 20/Q.771
.ce
\fBTR\(hyU\(hyABORT Primitives\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(108p) | cw(60p) sw(60p) , ^  | c | c.
Parameter	Primitive: TR\(hyU\(hyABORT
	Request	Indication
_
.T&
lw(108p) | cw(60p) | cw(60p) .
Transaction ID	M	M
_
.T&
lw(108p) | cw(60p) | cw(60p) .
User Abort Information	O	O (=)
_
.TE
.nr PS 9
.RT
.ad r
\fBTable 20/Q.771 [T21.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.sp 2P
.LP
3.2.6
	\fIAbnormal situations\fR 
.sp 1P
.RT
.sp 1P
.LP
3.2.6.1
	\fIAbort by the Transaction Sub\(hylayer\fR 
.sp 9p
.RT
.PP
The abort facility may be invoked by the Transaction sub\(hylayer in reaction 
to abnormal situations. The possible reasons for such a decision are indicated 
in Recommendation\ Q.774. 
.PP
Transaction abort causes the abandonment of any message of the
transaction for which transmission is pending.
.bp
.PP
Transaction abort is made by means of the TR\(hyP\(hyABORT indication
primitive described by Table\ 21/Q.771.
.RT
.ce
\fBH.T. [T22.771]\fR 
.ce
TABLE\ 21/Q.771
.ce
\fBTransaction sub\(hylayer abort primitive\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(78p) | cw(90p) , ^  | c.
Parameter	Primitive
	TR\(hyP\(hyABORT indication
_
.T&
lw(78p) | cw(90p) .
Transaction ID	M
_
.T&
lw(78p) | cw(90p) .
P\(hyabort	M
_
.TE
.nr PS 9
.RT
.ad r
\fBTable 21/Q.771 [T22.771], p.  \fR 
.sp 1P
.RT
.ad b
.RT
.PP
Figure 13/Q.771 shows the state transitions for transaction abort. The 
states are those defined in\ \(sc\(sc\ 3.2.3 and\ 3.2.4 above. 
.LP
.rs
.sp 14P
.ad r
\fBFigure 13/Q.771 [T23.771], p.\ (traiter comme tableau MEP)\fR 
.sp 1P
.RT
.ad b
.RT
.sp 1P
.LP
3.3
	\fIServices provided by the ISP\fR 
.sp 9p
.RT
.PP
No additional service is provided by the ISP when the TC\(hyservice is 
based on a connectionless network service. 
.RT
.sp 1P
.LP
3.4
	\fIServices assumed from the connectionless network layer\fR 
.sp 9p
.RT
.PP
In the Signalling System\ No.\ 7 environment, the services assumed
from the SCCP are those defined in Recommendation\ Q.711, \(sc\ 2.2 (SCCP
Connectionless Services, class\ 0 or class\ 1).
.PP
Relations of TC with the SCCP management require further study.
.RT
.sp 2P
.LP
\fB4\fR 	\fBService provided by TC based on a connection\(hyoriented network
service\fR 
.sp 1P
.RT
.PP
For further study.
.bp
.RT
.sp 2P
.LP
\fBRecommendation Q.772\fR 
.RT
.sp 2P
.sp 1P
.ce 1000
\fBTRANSACTION\ CAPABILITIES\ INFORMATION\ ELEMENT\ DEFINITIONS\fR 
.EF '%	Fascicle\ VI.9\ \(em\ Rec.\ Q.772''
.OF '''Fascicle\ VI.9\ \(em\ Rec.\ Q.772	%'
.ce 0
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.LP
\fR \fB1\fR 	\fBGeneral\fR 
.sp 1P
.RT
.PP
This Recommendation describes the individual information elements and parameters 
used within Transaction Capabilities messages. The encoding and 
formatting of these elements are shown in Recommendation Q.773.
.PP
The meaning of each information element is described in general
terms.
.PP
For TC based upon a connectionless network service, the current TC
is equivalent to the Transaction Capabilities Application Part (TCAP).
.PP
The TCAP message format consists of two parts, namely the transaction
portion and the component portion.  Information in the component portion
concerns individual operations and their replies. The transaction portion
contains protocol control information for the transaction sub\(hylayer.
.PP
For a more detailed analysis of the architecture, see\fR Figure\ 3/Q.771, 
and associated text. 
.RT
.sp 2P
.LP
\fB2\fR 	\fBTransaction portion\fR 
.sp 1P
.RT
.PP
The transaction portion of a TC message may contain the following
information elements, viz:
.RT
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.LP
2.1
	\fIMessage type\fR 
.sp 9p
.RT
.PP
Five types of messages are defined for the transaction portion as
follows:
.RT
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.LP
2.1.1
	\fIUnidirectional\fR 
.sp 9p
.RT
.PP
This message is used when there is no need to establish a
transaction with another peer TR\(hyUser.
.RT
.sp 1P
.LP
2.1.2
	\fIBegin\fR 
.sp 9p
.RT
.PP
This message is used to initiate a transaction with another peer\fR 
TR\(hyUser.
.RT
.sp 1P
.LP
2.1.3
	\fIEnd\fR 
.sp 9p
.RT
.PP
This message is used to terminate a transaction with another peer\fR TR\(hyUser. 
.RT
.sp 1P
.LP
2.1.4
	\fIContinue\fR 
.sp 9p
.RT
.PP
This message is used to complete the establishment of a transaction and 
to continue an established transaction. 
.RT
.sp 1P
.LP
2.1.5
	\fIAbort\fR 
.sp 9p
.RT
.PP
This message is used to terminate a transaction following an abnormal situation 
detected by the transaction sub\(hylayer (the service provider), or to 
abort a transaction by the TR\(hyUser (the service user). 
.RT
.sp 1P
.LP
2.2
	\fITransaction IDs\fR 
.sp 9p
.RT
.PP
Transaction IDs are independently assigned by each of the two nodes communicating 
via a transaction, enabling each node to uniquely identify the 
transaction and associate the entire contents of the message with that
particular transaction. There are two types of Transaction IDs, viz:
.bp
.RT
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2.2.1
	\fIOriginating Transaction ID\fR 
.sp 9p
.RT
.PP
The Originating Transaction ID is assigned by the node sending a
message, and is used to identify the transaction at that end.
.RT
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2.2.2
	\fIDestination Transaction ID\fR 
.sp 9p
.RT
.PP
The Destination Transaction ID identifies the transaction at the
receiving end. The first Originating Transaction ID value received is reflected 
as the Destination Transaction ID value. 
.RT
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.LP
2.3
	\fIP\(hyAbort Cause\fR 
.sp 9p
.RT
.PP
This is used when the transaction sub\(hylayer aborts a transaction.
.PP
P\(hyAbort cause definitions are as follows:
.RT
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.LP
2.3.1
	\fIUnrecognized Message Type\fR 
.sp 9p
.RT
.PP
The message type is not one of those defined in \(sc\(sc\ 2.1.1 to
2.1.5 above.
.RT
.sp 1P
.LP
2.3.2
	\fIUnrecognized transaction ID\fR 
.sp 9p
.RT
.PP
A transaction ID has been received for which a transaction does not exist 
at the receiving node. 
.RT
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.LP
2.3.3
	\fIBadly formatted transaction portion\fR 
.sp 9p
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.PP
The transaction portion of the received message does not conform to the 
X.209 encoding rules as outlined in Recommendation\ Q.773, \(sc\ 3. 
.RT
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.LP
2.3.4
	\fIIncorrect transaction portion\fR 
.sp 9p
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.PP
The elemental structure within the transaction portion of the
received message, does not conform to the rules for the transaction portion
defined in Recommendation\ Q.773 \(sc\ 5.
.RT
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.LP
2.3.5
	\fIResource limitation\fR 
.sp 9p
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.PP
Sufficient resources are not available.
.RT
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.LP
2.4
	\fIUser abort information\fR 
.sp 9p
.RT
.PP
This is used to pass User Specified Information by the TR\(hyUser when 
it aborts a transaction. 
.RT
.sp 1P
.LP
2.5
	\fIComponent portion\fR 
.sp 9p
.RT
.PP
This contains the component portion. When the component portion is empty 
this information element is not present. 
.RT
.sp 2P
.LP
\fB3\fR 	\fBComponent Portion\fR 
.sp 1P
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.PP
The Component Portion contains the following types of information
elements. They are delivered to the user at the receiving end in the same 
order in which they were received from the user at the originating end. 
.bp
.RT
.sp 1P
.LP
3.1
	\fIComponent type\fR 
.sp 9p
.RT
.PP
There are five types of component that may be present in the
Component Portion of a TC message. The four Protocol Data Units (PDUs)
defined in\fR Recommendation X.229 are used, viz:
.RT
.ce
\fBH.T. [T1.772]\fR 
.ps 9
.vs 11
.nr VS 11
.nr PS 9
.TS
center box;
cw(72p) | cw(36p) .
TCAP component	X.229 PDU
_
.T&
lw(72p) | cw(36p) .
Invoke	ROIV
_
.T&
lw(72p) | cw(36p) .
Return result (last)	RORS
_
.T&
lw(72p) | cw(36p) .
Return error	ROER
_
.T&
lw(72p) | cw(36p) .
Reject	RORJ
_
.TE
.nr PS 9
.RT
.ad r
\fBTable [T1.772], p.\fR 
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.ad b
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.PP
The remaining component type \(hy Return Result (Not Last) \(hy is defined 
by TCAP. 
.PP
These component types are defined as follows:
.RT
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3.1.1
	\fIInvoke\fR 
.sp 9p
.RT
.PP
The invoke component requests that an operation be performed. It may be 
linked to another operation invocation previously sent by the other 
end.
.RT
.sp 1P
.LP
3.1.2
	\fIReturn result (Not Last)\fR 
.sp 9p
.RT
.PP
When TC uses a connectionless Network Service, it may be necessary
for the TC\(hyUser to segment the result of an operation. In this case this
component is used to convey each segment of the result except the last, 
which is conveyed in a Return Result (Last) component. 
.RT
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.LP
3.1.3
	\fIReturn result (Last)\fR 
.sp 9p
.RT
.PP
The Return Result (Last) component reports successful completion of an 
operation. It may contain the last/only segment of a result. 
.RT
.sp 1P
.LP
3.1.4
	\fIReturn error\fR 
.sp 9p
.RT
.PP
The Return Error component reports that an operation has not been
successfully completed.
.RT
.sp 1P
.LP
3.1.5
	\fIReject\fR 
.sp 9p
.RT
.PP
The Reject component reports the receipt and rejection of an
incorrect component, other than a Reject component. The possible causes for
rejecting a component are defined by the Problem Code element in \(sc\ 3.8.
.RT
.sp 1P
.LP
3.2
	\fIInvoke ID\fR 
.sp 9p
.RT
.PP
An Invoke ID is used as a reference number to identify uniquely a
request for an operation. It is present in any reply to an Invoke component
(Return Result, Return Error or Reject), enabling the reply to be correlated
with the invoke.
.RT
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.LP
3.3
	\fILinked ID\fR 
.sp 9p
.RT
.PP
A Linked ID is included in an invoke component by a node when it
responds to an operation invocation with a linked operation invocation. The
node receiving the Linked ID uses it for correlation purposes, in the same 
way that it uses the invoke ID in Return Result, Return Error and Reject 
components.
.RT
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.LP
3.4
	\fIOperation code\fR 
.sp 9p
.RT
.PP
The Operation Code element indicates the precise operation to be
invoked, and is present in an invoke component type. The operation may be a
local operation or a global operation. A local operation can be used in 
one ASE only. The same global operation can be used in several different 
ASEs. 
.bp
.PP
The actual operation codes, the definition of the operations and
their associated parameters, are defined in relevant ASE specifications. The
component sub\(hylayer does not set or examine the operation code value, 
nor which parameters are present, nor the parameter values. 
.RT
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3.5
	\fISet (of parameters)\fR 
.sp 9p
.RT
.PP
The Set element is used to contain a set of parameters accompanying a component. 
It is required in the case of more than one parameter being 
included in a component. The parameters themselves are defined in relevant 
ASE specifications. 
.RT
.sp 1P
.LP
3.6
	\fISequence (of parameters)\fR 
.sp 9p
.RT
.PP
The Sequence element is used similarly to the Set element, except
that a specific sequence of parameters is included in the component.
.RT
.sp 1P
.LP
3.7
	\fIError code\fR 
.sp 9p
.RT
.PP
The Error Code element contains the reason why an operation cannot be completed 
successfully. It is present only in a Return Error component. As with operations, 
errors may be local or global. 
.PP
These errors and associated parameters are defined in relevant ASE
specifications.
.RT
.sp 1P
.LP
3.8
	\fIProblem code\fR 
.sp 9p
.RT
.PP
The Problem code element contains the reason for the rejection of a component, 
and one such element is present in a Reject component. Four problem code 
elements are defined, viz: 
.RT
.sp 1P
.LP
3.8.1
	\fIGeneral problem\fR 
.sp 9p
.RT
.PP
This element contains one of the problem codes which apply to the
component sub\(hylayer in general, and which do not relate to any specific
component type. All of these are generated by the component sub\(hylayer. They
are:
.RT
.sp 1P
.LP
3.8.1.1
	\fIUnrecognized component\fR 
.sp 9p
.RT
.PP
The component type is not recognized as being one of those defined in \(sc\ 
3.1. 
.RT
.sp 1P
.LP
3.8.1.2
	\fIMistyped component\fR 
.sp 9p
.RT
.PP
The elemental structure of a component does not conform to the
structure of that component as defined in Recommendation\ Q.773 \(sc\ 6.
.RT
.sp 1P
.LP
3.8.1.3
	\fIBadly structured component\fR 
.sp 9p
.RT
.PP
The contents of the component do not conform to the encoding rules
defined in Recommendation\ Q.773 \(sc\ 3.
.RT
.sp 1P
.LP
3.8.2
	\fIInvoke problem\fR 
.sp 9p
.RT
.PP
This element contains one of the problem codes which relate only to the 
invoke component type. They are: 
.RT
.sp 1P
.LP
\fR 3.8.2.1
	\fIDuplicate invoke ID\fR 
.sp 9p
.RT
.PP
The invoke ID is already in use by a previously invoked operation.
This code is generated by the TC\(hyUser.
.RT
.sp 1P
.LP
3.8.2.2
	\fIUnrecognized operation\fR 
.sp 9p
.RT
.PP
The operation code value is not one of those used by the ASE. This
code is generated only by the TC\(hyUser.
.RT
.sp 1P
.LP
3.8.2.3
	\fIMistyped parameter\fR 
.sp 9p
.RT
.PP
A parameter tag is not one of those associated with the operation
invoked. This code is generated only by the TC\(hyUser.
.bp
.RT
.sp 1P
.LP
3.8.2.4
	\fIResource limitation\fR 
.sp 9p
.RT
.PP
Sufficient resources are not available to perform the operation
requested. This code is generated by the TC\(hyUser.
.RT
.sp 1P
.LP
3.8.2.5
	\fIInitiating release\fR 
.sp 9p
.RT
.PP
The operation requested cannot be invoked as the dialogue is about
to be released. This code is generated only by the TC\(hyUser.
.RT
.sp 1P
.LP
3.8.2.6
	\fIUnrecognized linked ID\fR 
.sp 9p
.RT
.PP
The linked ID does not correspond to a previously invoked operation. This 
code is generated only by the component sub\(hylayer. 
.RT
.sp 1P
.LP
3.8.2.7
	\fILinked response unexpected\fR 
.sp 9p
.RT
.PP
The operation referred to by the linked ID is not an operation for
which linked invokes are allowed. This code is generated only by the
TC\(hyUser.
.RT
.sp 1P
.LP
3.8.2.8
	\fIUnexpected linked operation\fR 
.sp 9p
.RT
.PP
The linked operation is not one of those that the operation referred to 
by the linked ID allows. This code is generated only by the TC\(hyUser. 
.RT
.sp 1P
.LP
3.8.3
	\fIReturn result problem\fR 
.sp 9p
.RT
.PP
This element contains one of the problem codes which relate only to the 
return result component type. 
They are:
.RT
.sp 1P
.LP
3.8.3.1
	\fIUnrecognized invoke ID\fR 
.sp 9p
.RT
.PP
No operation with the specified invoke ID is in progress. This code is 
generated by the component sub\(hylayer. 
.RT
.sp 1P
.LP
3.8.3.2
	\fIReturn result unexpected\fR 
.sp 9p
.RT
.PP
The invoked operation does not report success. This code is
generated by the component sub\(hylayer.
.RT
.sp 1P
.LP
3.8.3.3
	\fIMistyped parameter\fR 
.sp 9p
.RT
.PP
A parameter tag is not one of those associated with the outcome of
the operation. This code is generated only by the TC\(hyUser.
.RT
.sp 1P
.LP
3.8.4
	\fIReturn error problem\fR 
.sp 9p
.RT
.PP
This element contains one of the problem codes which relate only to the 
return error component type.\fR They are: 
.RT
.sp 1P
.LP
3.8.4.1
	\fIUnrecognized invoke ID\fR 
.sp 9p
.RT
.PP
No operation with the specified invoke ID is in progress. This code is 
generated by the component sub\(hylayer. 
.RT
.sp 1P
.LP
3.8.4.2
	\fIReturn error unexpected\fR 
.sp 9p
.RT
.PP
The invoked operation does not report failure. This code is
generated by the component sub\(hylayer.
.RT
.sp 1P
.LP
3.8.4.3
	\fIUnrecognized error\fR 
.sp 9p
.RT
.PP
The reported error is not one of those defined for the ASE. This code is 
generated by the TC\(hyUser. 
.RT
.sp 1P
.LP
3.8.4.4
	\fIUnexpected error\fR 
.sp 9p
.RT
.PP
The received error is not one of those which the invoked operation
may report. This code is generated by the TC\(hyUser.
.RT
.sp 1P
.LP
3.8.4.5
	\fIMistyped parameter\fR 
.sp 9p
.RT
.PP
A parameter tag is not one of those associated with the outcome of
the operation. This code is generated only by the TC\(hyUser.
.RT
.LP
.bp