Jiri Kuthan writes:
What is "proper value"?
jiri,
according to rfc3261 section 20.42:
For implementations compliant to this specification, the value of the branch parameter MUST start with the magic cookie “z9hG4bK”, as discussed in Section 8.1.1.
it is sad if sr is not BY DEFAULT rfc3261 compliant.
- according to core cookbook, syn_branch core param only affects
stateless forwarding. in my config, all acks are t_relayed, i.e., syn_branch param should not have any effect, but is does. how is that possible? is there a bug in core cookbook?
In fact, ACK is forwarded statelessly even when INVITE is processed using TM.
then perhaps it would be a good idea to mention this in core cookbook.
- should t_relaying of acks to 200 oks use proper (i.e.. non 0)
Not sure what "proper" would be, as the branch parameter doesn't play any role for matching messages neither downstream nor at SR. We can make it "look better" but I'm wondering if it would improve something.
see above. we have seen rfc3261 sip user agents that don't understand branch=0 value and matching of ack fails. so instead of doing full md5 calculation, it would make sense to use rfc3261 compliant constant rather than 0.
-- juha