1. Virtual Signaling Transfer Point User Guide
  2. vSTP Features
  3. In-Sequence Delivery of Class 1 UDT Messages

2.11 In-Sequence Delivery of Class 1 UDT Messages

The In-Sequence Delivery of Class 1 UDT Messages provides for the sequencing for both UDT and XUDT Class 1 MSUs. All UDT/XUDT Class 1 messages are routed out in the same order that they were received. To enable the sequencing of UDT/XUDT Class 1 messages, the class1seq parameter value of the SCCP options using MMI is set to on.

When the class1seq parameter value is off, load sharing of the UDT/XUDT Class 1 messages is performed using the load sharing configuration in the MAP and MRN tables. The delivery of the UDT/XUDT Class 1 messages in sequence is not guaranteed.

If the messages are not in the correct sequence when they arrive, they are not delivered to the next node in the correct sequence. Message re-sequencing is the responsibility of the originating and destination nodes.

GT-routed Class 0 UDT/XUDT messages are not sequenced.