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determines the next hop is proxy biloxi.com, and passes this
message to it.
Finally bob’s phone rings, also this triggers a message passed
back to Alice’s user agent, producing a ring-back tone in Alice’s
phone. Once Bob hooks up his phone, a 2-way voice stream is
created.
Call Flow in Redirect Mode
In this flow, Alice calls Bob at
. Alice’s user agent
sends the SIP message to its proxy, but gets a 302 message,
indicating Bob now is resided in another location. Also this
response also guides Alice how to reach its new location,
. This time Alice knows the correct location of Bob,
and the call flow is like the ones in previous section.
