Extension Dialing Through Expressway

[abdul rasheed]

Dear All,

We are planning to deploy Expressway B2B for communicating between two different clusters where direct IP communication between the IP Phones is not possible. My concern is that Expressway B2B supports extension dialing. 

Thank You 

[Roger Kallberg]

You would be better of if you look at using an SBC, such as Cube for example, to interconnect the two disconnected clusters. AFAIK you would not succeed with true extension calling with B2B. It can for sure support 1234567@domain.com, but that’s not really the same thing that you ask for.

[abdul rasheed]

Hello Roger,

Thanks a lot for your response.

We have video conferencing included as well. So, as per Cisco TAC and AM, it will be difficult to have CUBE in between them. 

Also, we will be having two different domains for these two networks. 

Can we do some transforms and make extension dialing working? 

1. User A on Network A  dials User B on Network B (1001->2001)

2. CUCM of Network A sends the calls to the Expressway C of Network A (2001@ip-expressway)

3. Expressway C of network A transforms the URI to 2001@domainb.com and sends that call to Expressway E of Network A.

4. Expressway E of network A make DNS SRV query and find the Expressway E of network B. 

5. Expressway E of Network B sends the call to the Expressway C of network B. 

6. Expressway C of Network B transforms the URI to 2001 and sends the calls to CUCM of Network B. 

Will this work? 

[Roger Kallberg · Accepted solution]

Possibly. I guess the best option for you is to set it up and try it out. In theory it should be doable. For the extension dialing I think that you should be able to use route pattern(s) and point it to route list of the B2B. However this would not do any transform of the domain part, for this you’ll have to look for what can be done in Expressway.