SCCP Messages
The Signalling Connection Control Part (SCCP) message are used by the peer to peer protocol. Following are the SCCP message used by the peer to connection oriented and connection less services. Application that uses the service of SCCP are called Subsystems. Refer the SCCP structure for detail SCCP structure. Classes of service : • Class 0 —Basic connectionless class - it has no sequencing control. i does not impose any condition on SLS, therefore SCCP message can be delivered in out-of-sequece. • Class 1 —In-sequence delivery connectionless class - it adds the sequence control to class 0 service by requiring to insert the same SLS to all NSDU. • Class 2 —Basic connection-oriented class - Assign the local reference numbers (SLR,DLR) to create logical connection. it does not provide the flow control, loss, and mis-sequence detection. • Class 3 —Flow control connection-oriented class - Class 3 is an enhanced connection-oriented service that offers detection of