SCCP service users

NMS SCCP supports one or more applications with service access points, or SAPs. One SAP is defined for each application that uses the SCCP service. At initialization, an application binds to a particular SAP specifying the SAP ID. Each user SAP is associated with a single SCCP subsystem number. All SCCP messages destined for a particular subsystem number are routed to the application bound to the SAP associated with that subsystem number. SAPs are shown in the following illustration:

An application can implement multiple subsystems by binding to multiple SCCP SAPs, as shown in the previous illustration. If an application supports multiple TX boards, it must bind with each board separately.

Note: The number of SAPs and the characteristics of each SAP are specified at SCCP configuration time. Refer to the NMS SS7 Configuration Manual for more information.

Each SAP (and subsystem number) can optionally have a backup point code (a backup node that implements the same subsystem), a set of concerned point codes that are notified by the SCCP task whenever the availability of the subsystem changes, or both.