I've looked so much on the internet, but I could not find a any SIP unregister example, and when I search RFC 3261,3665 the word does not even appear, perhaps I'm searching for the wrong phrase. I manage to understand the part of setting the expires to zero, but it still does not work and I could not find documentation about how a formal unregister should be.
Does anyone knows how to compose an Unregister SIP Request? or what should I search for it?
Best Answer
An "unregister" is a REGISTER wherein you set the expires for one or more Contact URIs to 0. You may do so either with the Expires header -
Expires: 0
- which applies to all Contact URIs in the REGISTER, or with a parameter -Contact: <sip:foo@bar>;expires=0
- which will only affect that URI's registration.You may also unregister ALL contact URIs for your address-of-record by adding
Contact: *
andExpires: 0
.