Columbia VoIP Testbed
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Issue #5: Unsuccessful cancellation of registration Category Incorrect implementation of the specification Description RFC 3261 describes and RFC 3665 illustrates how to correctly and completely perform a registration cancellation. We have seen end-clients and servers that incorrectly implement the cancellation of registration. Implications Such an unsuccessful cancellation of registrations may lead to undesirable behavior during signaling, due to incorrect Address of Record (AOR) details.
Instance #1 When the Eyebeam client is exited, it does not resend the registration cancellation request upon getting ‘401 Unauthorized’ response from the registrar. Packet traces / Call-flows Eyebeam registration Fixes / Workarounds None. References 1. RFC 3665 - Session Initiation Protocol Basic Call Flow Examples (www.ietf.org/rfc/rfc3665.txt) Instance #2 The second one concerns the use of ‘*’ in the contact header, which requests the registrar to remove all contract bindings for the user. We have observed that not all registrars honor such requests for registration cancellation. Packet traces / Call-flows 3Com server, failing to honor ‘*’ in the contact header of the register request. Fixes / Workarounds None. References 1. RFC 3261 - SIP: Session Initiation Protocol (www.ietf.org/rfc/rfc3261.txt)