[Users] Help with SER and B2BUA

[Klaus Darilion]

Marco Meinardi wrote:
> Dear Guys,
> 
> I still need help designing my SER architecture. I have to implement 
> prepaid system with customized billing methods and I have been advised 
> to use Asterisk B2BUA.
> 
> SER and Asterisk will handle signalling, Mediaproxy will handle ALL RTP 
> streams.
> 
> UAc ---> SER: Auth, Loc ---> Asterisk B2BUA ---> UAs
>           |_____________________________|
>              Mediaproxy
> 
> I want to keep SER as my central SIP proxy performing user registration, 
> authentication and location, using Asterisk only for terminating 
> ongoigng calls after the credit is over. An external perl application 
> will calculate the time that the call should last, according to remaning 
> credit, Asterisk will decrement this time counter and terminate the call 
> when it reaches to 0.
> Subtracting credit will be done in post-processing reading SER acc table.
> 
> Please advise me, by telling me if this is the correct approach and if 
> it possible to implement.

Yes, you can. But first think about if it is really necessary to use 
(open)ser at all? How many acitive users you will have? Also Asterisk 
can act as Registrar.

Further, as Asterisk is capable of NAT traversal, I think there is no 
need for mediaproxy. Make SIP NAT traversal on the proxy, and Asterisk 
will do the RTP NAT traversal (nat=yes, canreinvite=no)

regards
Klaus