- When an application binds to it, MTP 3 will generate a StatResumed indication (see Section 2.11) for each configured destination that is currently available. This allows an application to determine the initial status of all configured destinations by assuming all are unavailable until a StatResumed is received.
- The SIO must be unique for each application. The service information field is composed of Service Indicator and Network Indicator fields. Only the Service Indicator field is used for routing of incoming messages.
- As defined by ANSI, the following values may be used for the Service Indicator portion of the SIO:
0x03 SCCP
0x04 TUP
0x05 ISDN User Part
0x06 DUP (call and circuit messages)
0x07 DUP (registration & cancellation messages)
0x09 - 0x0F Spare
- The following four values are defined for network indicator codes. This field does not affect routing of incoming messages.
0x00 International network
0x40 Spare
0x80 National network
0xC0 Reserved for national use
- The sapId value must be unique to MTP 3 and be a previously configured NSAP ID. It is sent by the application program in requests, and returned by MTP 3 in indications. The SAP can be viewed as a logical port or channel into the MTP 3 process.
- Each user application of MTP 3 must have a unique source entity ID. In addition, each user application must have an instance ID, which is set to zero for all host applications. For more information on entity and instance IDs, refer to Section 2.7.
- The value entered for suId will be returned by MTP 3 in all subsequent messages to the application belonging to the SAP with which it is associated.
(Page 2 of 9 in this chapter) Version