[Asterisk-Users] SIP protocol bug ???

[Olle E. Johansson]

mtm spm wrote:
> Hello,
> 
> I have a problem with asterisk when dial out to a SIP
> provider. 
> Asterisk send a INVITE with no credentials, the
> provider reply with a 401 Unauthorized.
> However, Asterisk DOES NOT resend the invite again
> with credentials. But it hangs there (maybe waiting
> for a ok)
> 
> It is this a bug in asterisk or the provider is 
> supposed to send something else rather than a 401
> as answer for a INVITE ?

Hello!
In the Asterisk command line interface, write "sip debug" to see all SIP transactions.

Make sure that asterisk actually receives the response from the SIP provider and that
there's no NAT disturbing the session. It sounds like Asterisk does not receive the
401 unauthorized and therefore tries again.

The first Invite is without credentials, since digest authentication needs input
from the server to create credentials.

If there's a NAT in the middle, you'll find plenty of documentation on how to solve
the problem (or not) on the Asterisk Wiki at http://www.voip-info.org

Best regards,
/Olle