[Serusers] SER and the SPA3000

[Andres]

We are planning to roll out services to our customers with the Sipura 
3000 FXO gateway.  The idea is that customers will be able to have their 
own personal PSTN gateway wherever they want.

In order to provide security, the SPA3000 allows you to configure digest 
authentication.  The idea is that an incoming INVITE will get challenged 
via a 401 response and then end device will generate that INVITE again 
with the proper credentials.  The idea here would be to fill in the same 
username/password details on the customer's FXO gateway as the ones we 
have on SER (where his other UA registers and places calls).  Something 
like:

UA1 ------>SER------>FXO1

We would expect that the UA1 sends the INVITE to SER, it gets challenges 
and autheticated properly, then that INVITE is routed to the FXO1, which 
challeneges it as well with a 401.  That 401 should be relayed back to 
UA1 so that it can generate the proper credentials again (this time for 
the FXO1). 

Unfortunatelly the 401 that the FXO1 sends back gets ACKed by SER but 
never relayed back to UA1. 

Is this doable, or should we switch to another means of authenticating 
that call on the FXO1?

Thanks,

-- 
Andres
Network Admin
http://www.telesip.net