[Serusers] From-Tag/Call-id not uniq?

[Jiri Kuthan]

At 12:06 PM 8/16/2004, Arnd Vehling wrote:
>Jiri Kuthan wrote:
>>Now to provide a complete answer to the question: the values are supposed to
>>be unique according to RFC3261 but there is nothing in the world that
>>prevents broken implementations to generate invalid non-unique values.
>>There are indeed implementations that are broken. To make CDRs as much
>>unique as you can, compose the identifier as a triple callid-fromtag-
>>totag. Composition of values generated by UACs and UASs significantly
>>reduces the chance of not being unique.
>
>Why does the formulation "significantly reduces the chance of not being unique" make me nervous? :)

I don't know, I am not a psychologist ;)

>May it be that the "SIP RFC Fathers" neglected the real-word issue of
>actually accounting sip-calls a bit? Making accounting dependant on
>client side software implementations doesnt seem a basicly good idea
>to me.

That's why RFC3261 identifies dialog by the triple, which includes 
server-generated to-tag. Obviously if clients and servers agree to
generate stupid triple {from-tag, callid, to-tag}, accounting can
still mess, but I don't see this case as a huge issue.

-jiri