Hello everyone :) I'm using the pjsip library for a short time I've noticed something that I can't make sense of. Registration on Pjsip (3 Requests) 1- Request: First Attempt of Registration. Response: 401 Unauthorized 2- Request: Second Attempt of Registration Adding the Authorization header. Response: 200 OK 3- Request: Third Attempt of Registration expiring the old contact with local IP and add a new contact with the public IP according to the flag (PJSUA_CONTACT_REWRITE_METHOD). Response: 200 OK Registration on Liblinphone (2 Requests) 1- Request: First Attempt of Registration. Response: 401 Unauthorized 2- Combines step 2 and 3 on the same request and that save a request. Can I know why pjsip is doing it this way? and how can I change this behavior to be like Liblinphone's one? Regards, Ahmed Hegazy -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.pjsip.org/pipermail/pjsip_lists.pjsip.org/attachments/20151014/65d15e9a/attachment.html>