According to SIP RFC:
" Call-ID contains a globally unique identifier for this call, generated by the combination of a random string and the softphone's host name or IP address. The combination of the To tag, From tag, and Call-ID completely defines a peer-to-peer SIP relationship between Alice and Bob and is referred to as a dialog. "
I would not bother about Call-ID repeating, in normal use it is rather impossible.
Thus if someone has the same Call-ID for more than one call, he has really serious broken UAs or phones. Or I miss smthing?
-- Arek Bekiersz
Frank Fischer wrote:
On Thu, 01 Dec 2005 11:34:51 +0100, Erik wrote
Arek Bekiersz wrote:
It is usually enough to match INVITE with --first-- of
recorded BYEs
with the same CallID. It is fairly accurate.
Not if there are 2 calls at the same time using the same call_id
While this is technically against the RFC, there was some discussion that, on occasion, a UA would reuse a callID... but there should be NO situation in which 2 UAs are simultaneously using the same CallID unless you wrote the UA yourself to specifically do this. Do you have information about which UAs were doing this? I'd like to know which UAs to bar from usage on my network. :)
If i understand this right, the UAs are choosing the callId? If so, how could an UA know if the callId it has choosen, isn't already used by another UA in another call? Based on what are callIds created by the UA? Is there some part in the callId which is unique for a certain UA (in fact i see that the ip address of the client is a part of the callId, but this would be not unique enough i guess). Or does SER check for same CallIDs on different simultaneouse calls to make sure that their is no such case? This would mean SER would have to reject calls with same callIds?
- Frank