This ITU-T Recommendation, Application Transport Mechanism (APM), is an addition to the B-ISDN User Part (B-ISUP) that provides a transport mechanism for its applications requiring a bearer and, in conjunction, support the application's signalling information flow. This transport mechanism provides the same capabilities as that which the Transaction Capabilities Application Part (TCAP) provides its user. The basic function of the Application Transport Mechanism is to create signalling associations between the APM-user application logic located at a public initiating node (PIN) and its per APM-user application located at the public address node.