On Dec 22, 2024, at 12:38 pm, Olle E. Johansson oej@edvina.net wrote:
On 22 Dec 2024, at 16:45, Alex Balashov via sr-users sr-users@lists.kamailio.org wrote:
Although I admire Nick's work, and his gift for making complex concepts accessible to a lay audience--I've learned quite a bit from his posts myself--some of the misinformation and simplification in this one is unforgivable, e.g.
"A Transaction Stateful proxy stores state from the initial INVITE until a 200 OK is received. As soon as the session is setup it forgets everything. This means we won’t have any state information when the BYE is eventually received."
This is radioactively wrong.
Apart from missing the ACK, what do you think is wrong with this?
It doesn't really describe what transactions are or how they work:
- Any request can form a transaction;
- A transaction exists for the entire lifecycle of the request, starting from the request, encapsulating zero or more 1xx provisional messages (if applicable), and a final dispositive reply;
- A 200 OK is not the only final dispositive reply at the end of a transaction life cycle.
This is so obvious to experienced SIP folks that we don't even think about it, but an article aiming to digest this subject matter closer to the entry level can do better.
-- Alex