Hi Daniel, Alex and all
I'm having an argument with the Vendor of our SBC towards IC carriers.
According to $vendor tech, if the SIP Message was received via UDP, the transport= attribute of the Contact Header has no meaning and therefore the RURI of a following transaction (like BYE) will not contain a transport attribute as the reply is sent via UDP.
This of course breaks communication CPE behind a kamailio proxy which are connected via TCP or TLS.
I've been looking through RFC3261 and I find various examples how the transport attribute can be used.
But I fail to find, that a transport received in the Contact header MUST be re-used in the RURI of subsequent transactions within one dialogue.
From my point of view, this is logical and this is how various devices I have tested operate. But with a commercial vendor, if it's not in the RFC it's no Bug and won't be fixed... Does anyone know in which section (or maybe other RFC) this is covered?
Mit freundlichen Grüssen
-Benoît Panizzon-