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Appendix
1069
3.
User A places User B on hold.
User A
Proxy Server
User B
F1. INVITE B
F2. INVITE B
F7. ACK
F8. ACK
F3. 180 Ringing
F6. 200 OK
F5. 200 OK
F4. 180 Ringing
F12. 200 OK
F9. INVITE B (sendonly)
F10. INVITE B (sendonly)
F11. 200 OK
F14. ACK
F13. ACK
No RTP packets being sent
2-way RTP channel established
Step
Action
Description
F1
INVITE—User A to Proxy Server
User A sends an INVITE message to a
proxy server. The INVITE request is an
invitation to User B to participate in a call
session.
In the INVITE request:
The IP address of User B is inserted
in the Request-URI field.
User A is identified as the call
session initiator in the From field.
A unique numeric identifier is
assigned to the call and is inserted in
the Call-ID field.
The transaction number within a
single call leg is identified in the
Summary of Contents for SIP-T54S
Page 1: ...63...
Page 51: ...Getting Started 25 For SIP T46G S Desk Mount Method Wall Mount Method Optional...
Page 53: ...Getting Started 27 For SIP T42S T41S Desk Mount Method Wall Mount Method Optional...
Page 55: ...Getting Started 29 For SIP T23P T23G Desk Mount Method Wall Mount Method Optional...
Page 70: ...Administrator s Guide for SIP T2 Series T19 P E2 T4 Series T5 Series CP860 CP920 IP Phones 44...
Page 194: ...Administrator s Guide for SIP T2 Series T19 P E2 T4 Series T5 Series CP860 CP920 IP Phones 168...