英SIGTRAN.ppt

SIGTRAN Objectives On completion of this module the student will be able to: Explain the benefit of using SIGTRAN in terms of signalling network planning, and signalling network capacity Draw SIGTRAN protocol stacks and explain the role of each layer Outline the procedures for creation of SIGTRAN signalling definitions in DX200 Monitor and explain SIGTRAN messages from Ethereal or other signalling monitoring tool SIGTRAN Protocol stack options Use of SIGTRAN SCTP Functions Association Start-up and Takedown Sequenced Delivery within Streams User Data Fragmentation Acknowledgement and Congestion Avoidance Chunk Bundling Packet Validation ASP-SG communication IPSP-IPSP communication SCTP message structure SCTP normal association establishment SCTP association termination SCTP DATA chunk format SCTP SACK chunk format SCTP data transfer Use of SIGTRAN in CS Core rel.4 Example of SIGTRAN SG-ASP Use of SCCP relay function Signalling Point Management Cluster SIGTRAN DATA message structure LAN Structure LAN switch in DX200i cartridge SIGTRAN Message Monitoring * ? NOKIA MTPb.ppt/ 23.03.2003 / Marat Ivanov qchang: h INIT INIT ACK COOKIE ECHO Establishment SCTP SCTP COOKIE ACK DATA SACK SHUTDOWN SHUTDOWN ACK SHUTDOWN COMPLETE Graceful termination of the association SCTP SCTP ABORT Abort of the association 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 Type=0 Reserved U B E Length TSN Stream Identifier S Stream Sequence Number n Payload Protocol Identifier User Data (seq n of stream S) U flag – Unordered. Stream Sequence Number is not used B/E flags – indicate if this chunk is the beginning/middle/end or not fragmented chunk of user data 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 Type=3 Length Cumulative TSN Ack Duplicate TSN 1 Chunk Flags Advertised Receiver Window Credit a_rwnd Number of Gap Ack Blocks N Number of Duplicated TSNs X Gap Ack Block #1 start Gap Ack Block #1 end Gap Ack Block #N