RFC 3332 SS7 MTP3-User Adaptation Layer September 2002 3. M3UA Protocol Elements.......................................25 3.1 Common Message Header........................................26 3.2 Variable Length Parameter....................................29 3.3 Transfer Messages............................................31 3.4 SS7 Signalling Network Management (SSNM) Messages............35 3.5 ASP State Maintenance (ASPSM) Messages.......................45 3.6 Routing Key Management (RKM) Messages........................48 3.7 ASP Traffic Maintenance (ASPTM) Messages.....................59 3.8 Management (MGMT) Messages...................................63 4. Procedures...................................................69 4.1 Procedures to Support the M3UA-User .........................69 4.2 Procedures to Support the Management of SCTP Associations ...70 4.3 AS and ASP State Maintenance.................................72 4.4 Routing Key Management Procedures............................87 4.5 Procedures to Support the Availability or Congestion Status of SS7 Destination...........................................89 4.6 MTP3 Restart.................................................92 5. Examples of M3UA Procedures..................................93 5.1 Establishment of Association and Traffic Between SGs and ASPs.........................................93 5.2 ASP traffic Failover Examples................................99 5.3 Normal Withdrawal of an ASP from an Application Server and Teardown of an Association..............................100 5.4 M3UA/MTP3-User Boundary Examples............................101 5.5 Examples of IPSP communication..............................105 6. Security Considerations.....................................108 6.1 Introduction................................................108 6.2 Threats.....................................................108 6.3 Protecting Confidentiality..................................108 7. IANA Considerations.........................................109 7.1 SCTP Payload Protocol Identifier............................109 7.2 M3UA Port Number............................................109 7.3 M3UA Protocol Extensions....................................109 8. References...................................................111 8.1 Normative References........................................111 8.2 Informative References......................................111 9. Acknowledgements.............................................113 10. Document Contributors.......................................113 Appendix A......................................................114 A.1 Signalling Network Architecture.............................114 A.2 Redundancy Models...........................................117 Editors' Addresses..............................................119 Full Copyright Statement........................................120 Sidebottom, et. al. Standards Track