Administrator’s Guide for SIP-T2xP IP Phones
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response indicates that User B accepts
the transfer.
NOTIFY—User B to Proxy
Server
User B sends a SIP Notify message to
the proxy server. The Notify message
inform User A the state of User B.
NOTIFY—Proxy Server to User
A
The proxy server forwards the Notify
message to User A.
200 OK—User A to Proxy
Server
User A sends a SIP 200 OK response to
the proxy server. The 200 OK response
notifies the proxy server that User A has
received the Notify message.
200 OK—Proxy Server to User
B
The proxy server forwards the SIP 200
OK response to User B. The 200 OK
response notifies User B that User A has
received the Notify message
BYE—User A to Proxy Server
User A terminates the call session by
sending a SIP BYE request to the proxy
server. The BYE request indicates that
User A wants to release the call.
BYE—Proxy Server to User B
The proxy server forwards the BYE
request to User B.
200OK—User B to Proxy
Server
User B sends a SIP 200 OK response to
the proxy server. The 200 OK response
notifies User A that User B has received
the BYE request.
200OK—Proxy Server to User
A
The proxy server forwards the SIP 200
OK response to User A.