7.7 SIP timers

7.8 IM CN subsystem timers

7.4 Status-codes defined within the present document

7.5 Session description types defined within the present document

7.6 3GPP IM CN subsystem XML body

7.2 SIP header fields defined within the present document

7.2A Extensions to SIP header fields defined within the present document

7.3 Option-tags defined within the present document

7.1 SIP methods defined within the present document

5.13 ISC gateway function