Cisco VOIP solution for second office we are opening in another location

Posted on 2014-11-05
Last Modified: 2014-11-14
At my main office I have a single CUCM 7.1.5 server and Unity Connection 9.1.2 server.  My H.323 Voice gateway router is a Cisco 2821 Router, with all phone lines coming in on a T1 (PRI).

Here's my scenario.  We are going to open a second office in another state, employees here will basically be our 2nd shift, but I'm not sure how to go about routing calls to them.  For example if someone calls our main office at night, I want the call to be answered by the second shift employees who are staffed in another office in another state.

I thought about just registering some IP phone over a VPN connection back to our main office, but the are only going to have one internet circuit to start, so I don't want IP Phones to go down if one of the offices lose internet.  So i don't think that is a solution.

So i'm thinking about dropping a CME router out there, but I'm unsure how I would route calls from my main office to the second office.  See all our customers call 555-555-5555 at our main office, and our auto attendant (unity Connection) picks up, and customers go through the options to talk to who they need to,  so during 2nd shift how would I route the calls to be answered at the second office?

Any Advice or thoughts?
Question by:denver218
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Expert Comment

by:José Méndez
ID: 40424080
The most common deployment is as follows:
- CME router in remote location with its own PRI or FXO port
- Phones register to the CUCM 7 back at your main office (so far the CME feature is not used, the gateway acts as data link between the 2 sites)
- Callers calling 555 555 5555 hit Unity, where they hear a call handler with some options, they select 1 option and are router back into CUCM to the first shift employees.
- You can program the call handler in Unity to play the Standard greeting or another greeting based on time of the day, so depending on that, your users will hear one greeting and be routed to the first shift, or get an afterhours greeting and be routed to the second shift employees.

Now, the question is, when your callers call that particular 555 number, is your current config connecting them to Unity? Or do they go straight to the employees?
LVL 24

Accepted Solution

Ken Boone earned 500 total points
ID: 40424117
Just to clarify on willywilburwonka's comments.   You will not be using CME like he said, this would be just like your current h.323 voice gateway router.  You would want to have an SRST license though to provide failover capability for the phones if the link between offices goes down.      Basically everything at the new branch would simply be devices off of your existing phone system.  You do need to have ip connectivity between the two.

So think of it this way. The two locations are connected via IP (MPLS, maybe VPN, maybe something else)  You simply add another h.323 gateway at that locations.  It's just that this h.323 gateway is also configured for SRST.  You bring a PRI or POTS lines into this new voice gateway to support local calling and 911 from the branch.

Hope that helps.

Author Comment

ID: 40424546
So I could just get a 2900 series router with an SRST license right?  I would probably just put a VIC2-4FXO card in it with a few analog phone lines.  I've never used SRST.  So if I understand correctly if my VPN link to the main office goes down, the phones will register on the 2900 series router i have onsite with the SRST license and they will be able to make local calls right?  If this is the case, this could be a lot simpler than I anticipated.  Thanks for helping!
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LVL 24

Expert Comment

by:Ken Boone
ID: 40424581
Yes that is correct

Author Comment

ID: 40426841
Now can I do least cost routing voip between site A that has call manager and site b that has SRST?  

Site A (Call Manager)- Pennsylvania
Site B (SRST) - California

If I'm in PA and want to make a call to California, can the call go through Site B router that has the local lines in CA.  This would save money on long distance.
LVL 24

Expert Comment

by:Ken Boone
ID: 40426876
Yes you can configure toll bypass for that.  If you do that keep that in mind when you size how many FXO ports you need.

Author Closing Comment

ID: 40442433

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