[Linphone-developers] registration returns 401 always when the register timer expires??

[alvaro gala]

Hello to all.

I'm using the new libraries of eXosip2 and osip2 (3.1.0) and one system based on the last linphone.

I have a question about registrations with authentication

When my system registers against one Asterisk for first time, Asterisk returns it a  sip 401 Unauthorized message.
Then the system registers again with the auth info, and it is successful now. (Asterisk returns sip 200 OK)

This is completely normal, i think.

But my  question is:

When the timer of the register message expires, then linphone try to send another register message (with the auth info) to Asterisk. But this one returns and 401 again and one more time linphone has to send it another sip message in order to complete the register protocol. (but the auth info was in the message yet!) The systems continues working fine, but i don't understand why this second register fails, if it carries the authentication info.

Is this normal? Maybe is this the behaviour of the protocol when timer expires?

I have been proven the libeXosip2/tools/sip_reg program and i have realized that this occurs always when the timer expires. 
If the register message is sent before the expiration, Asterisk returns sip 200 OK

Thank you for all, Simon & Company.

Best regards.