7.4 A-P-ABORT service

The ACSE A-P-ABORT service shall be used by the UL service-provider to signal the abnormal release of the association due to problems in services at the Presentation Layer and below. This occurrence indicates the possible loss of information in transit. A-P-ABORT is a provider-initiated service.

Figure 7-4 illustrates aborting an established association by an UL service-provider.

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Figure 7-4 PROVIDER INITIATED ABORT

7.4.1 A-P-ABORT PARAMETER

Table 7-6 lists the parameter which shall be required for the A-P-ABORT service.

Table 7-6A-P-ABORT SERVICE PARAMETERS

A-P-ABORT Parameter Name Indication
provider reason P

The provider reason parameter shall be used to convey one of the following reasons:

a) reason-not-specified

b) unrecognized-pdu

c) unexpected-pdu

d) unexpected-session-service primitive

e) unrecognized-pdu parameter

f) unexpected-pdu parameter

g) invalid-pdu-parameter value

Note: In addition to these reasons, a locally defined list of reasons may be used to reflect errors that caused the abort and originated in the Session, Transport, Network, Data Link, and Physical layers. The generation and handling of such errors is internal to an implementation and, therefore, is outside the scope of this communications standard.

7.4.2 A-P-ABORT SERVICE PROCEDURE

When the UL service-provider detects an internal error, A-P-ABORT indication primitives shall be issued to acceptors in both AEs. The association shall be abnormally released. Requestors in both AEs shall not issue any further primitives for the association.