[SIPForum-discussion] SIPConnect question

[Mark R Lindsey]

I'll second Maulik's comments.


SIPConnect mandates TLS support, but does not require it to be used.  
E.g., "TLS-required=no" means that TLS must NOT be used. In those  
cases, ordinary SIP over TCP can be used, or SIP over UDP.

As to your question: the IP-PBX will need to register with the SP-SSE  
(which you reasonably called the SP SBC).

We could re-state your question this way: would the IP-PBX ever have  
direct signaling communication with the IC SBC? e.g.,

-- Would the SP-SSE ever return a 302 to the SIP-PBX, redirecting the  
call from the SIP-PBX via the IC SBC?

-- Would the SP-SSE ever redirect signaling through other mechanisms  
(Route / Via / Contact) via the IC SBC?

The spirit of SIPConnect, and the reference architecture, answer these  
two questions with a *no*. i.e., no communication would take place  
between the SIP-PBX and the IC SBC. The SP then accepts the  
responsibility of all communication with the International Carrier.

However, I can't find anything in SIPConnect 1.1 v14 spec that  
specifically prohibits the SP-SSE from redirecting signaling to some  
other SBC. (Someone who's completely studied a recent draft can  
correct me.)

 From the design perspective: there are definite advantages in using a  
model where all SIP-PBX signaling goes to and from the SP-SSE only. A  
couple of these are:

(a) It's much more conventional to have one service-provider-side  
signaling address, so you get the advantage of heavy SIP-PBX testing.

(b) It's much easier to troubleshoot it all of the signaling flows  
through the service provider's signaling endpoint.

Therefore, I strongly prefer to route all traffic through the service  
provider's SSE / SBC, and disallow signaling directly from the IP PBX  
to any other carrier.




Mark R Lindsey lindsey at e-c-group.com +12293160013 http://e-c-group.com/~lindsey



On Jul 12, 2009, at 4:00 PM, Yolanda Ruiz wrote:

> Hi,
> I´m pretty new with SIPtrunk concept and access scenarios. I have a  
> doubt about how SIPConnect should be set up in this scenario:
>
> IP-PBX in client-site ----  SP with register and SBC  ---  
> International Carrier
>
> The IP-PBX and the client belongs to the IC and to have connectivity  
> and local-phone numbers IC hires SP to connect in SIP-Trunk with the  
> IP-PBX.
>
> As SIP Connect implies TLS in signaling, should be TLS:
>
> 1- from IP-PBX in client site to SBC in SP
> 2- from IP-PBX in client site to IC SBC
>
> Which one of the two options should be the best one?
>