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UPDATE Method handling in SIP RA

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Joined: 2003-06-06

Again goes back to the Automatic Dialog Support business and I suppose it can be handled by adroit documentation. If an UPDATE arrives and a Dialog does not exist for the UPDATE, a User Agent (endpoint) should reply "481 Call/Transaction Not found" whereas a proxy should just proxy it. Trouble is, with Automatic Dialog Support disabled, the stack cannot tell what to do. Therefore this should be documented as being the responsibility of the Application.

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Joined: 2004-11-02

Just filling in from the previous discussion on this subject that the RA could respond "481 Call/Transaction Not found" in the case there was a dialog but it has ended.

This may not be the most likely scenario for the UPDATE method though.

Ranga, did you read the part about Proxy support as a future change?
With such support there can be a good case for providing nice functionality.

INVITE is proxied using a proxy activity and the Sbb is attached to the corresponding ACI.
UPDATE arrives at the RA.
RA detects that there is a proxy activity associated the the UPDATE and acts by proxying it.
This does require some extra functionality in the RA because the way to correlate the UPDATE to the proxy activity is via the dialog.

(UPDATE can only be sent if there is a dialog in early or confirmed state)