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Appendix
839
3.
User B hangs up.
User A
Proxy Server
User B
F1. INVITE B
F2. INVITE B
F3. 100 Trying
F9. ACK
F10. ACK
F5. 180 Ringing
2-way RTP channel established
F8. 200 OK
F7. 200 OK
F6. 180 Ringing
F4. 100 Trying
F11. BYE
F12. BYE
F13. 200 OK
F14. 200 OK
Step
Action
Description
F1
INVITE—User A to Proxy
Server
User A sends a SIP 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
Summary of Contents for Yealink SIP-T42G
Page 1: ......
Page 12: ...Administrator s Guide for SIP T2 Series T19 P E2 T4 Series CP860 IP Phones xii ...
Page 20: ...Administrator s Guide for SIP T2 Series T19 P E2 T4 Series CP860 IP Phones xx ...
Page 41: ...Getting Started 21 For SIP T46G Desk Mount Method Wall Mount Method Optional ...
Page 43: ...Getting Started 23 For SIP T29G T27P Desk Mount Method Wall Mount Method Optional ...
Page 45: ...Getting Started 25 For SIP T21 P E2 Desk Mount Method Wall Mount Method Optional ...
Page 678: ...Administrator s Guide for SIP T2 Series T19 P E2 T4 Series CP860 IP Phones 658 ...