GSM 09.02 - Version 5.3.0 - Digital cellular telecommunications - ETSI

12.6.8 Load control
Page 165
GSM 09.02 version 5.3.0: August 1996
As stated in the previous subclauses, before issuing a MAP-OPEN indication primitive the MAP PM
performs a check to verify if there are sufficient resources to open the dialogue taking into account
possible overload conditions.
The decision is based on the priority allocated to the application-context whose name is explicitly included
in the TC-BEGIN indication primitive or implied by the first operation invocation when V1 contexts are in
use. How a V1 application-context-name is derived from an operation code is described in table 12.1/1.
The priority level allocated to each application-context is described in clause 3 tables 3.1/1 and 3.1/2.
13 Mapping on to TC services
13.1 Dialogue control
Dialogue control services are mapped to TC dialogue handling services. The TC-UNI service is not used by
the MAP PM.
13.1.1 Directly mapped parameters
The following parameters of the MAP-OPEN request and indication primitives are directly mapped on to
the corresponding parameters of the TC-BEGIN primitives:
- destination address;
- originating address.
13.1.2 Use of other parameters of dialogue handling primitives
13.1.2.1 Dialogue Id
The value of this parameter is associated with the MAP PM invocation in an implementation dependent
manner.
13.1.2.2 Application-context-name
If it does not belong to the MAP V1 context set. The application-context-name parameter of a MAP
primitive is mapped to the application-context-name parameter of TC dialogue handling primitives
according to the rules described in subclause 12.1. Otherwise the application-context-name parameter of
TC dialogue handling primitives is never included.
13.1.2.3 User information
The user information parameter of TC dialogue primitives is used to carry the MAP dialogue APDUs.
13.1.2.4 Component present
This parameter is used by the MAP PM as described in CCITT Recommendation Q.771. It is not visible to
the MAP user.
13.1.2.5 Termination
The value of this parameter of the TC-END request primitive is set by the MAP PM on the basis of the
release method parameter of the MAP-CLOSE request primitive, except when the dialogue state machine
is in the state DIALOGUE INITIATED, in which case the Termination parameter shall always indicate
"pre-arranged end".