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Bridged numbers and 911 calls

Bridged numbers and 911 calls

Bridged numbers and 911 calls

I've got a Call Manager 9.1 system. I've got two locations - let's call them A and B. Location A routes calls out our (experimental) AT&T SIP trunk, and is the only location that does so. I have a user who "floats" between location A and location B has her location B phone number is bridged to a phone at location A.

Yesterday, this user made an accidental 911 call from her location B number while at location A. Not soon after, I got a nasty-gram from AT&T / IP-Flex about an invalid 10-digit IP-Flex number that went to the National 911 center instead of the local 911 center.

So my conundrum: When it comes to bridged appearences, how does one route the 911 call properly irrespective of what location this user is sitting? It seems like an impossible task. All of our DN's are in the "null" partition.

Any advice would be helpful...

RE: Bridged numbers and 911 calls

It's the css of the phone and the line itself that defines what route pattern/route list to route calls out.
If your phone at location B is sending 911 out of A's trunks, it's in the wrong css. Change the css on the phone or the DN on that phone, (however your site is conigured),to the proper css that routes calls out of the correct trunk. the caller ID that is getting send out will also need to be modified to the proper caller ID if AT&T is sending that to the 911 centered unaltered.

RE: Bridged numbers and 911 calls

Right, I know that the CSS defines the route. The issue is not that Location B's DN (non-SIP) is routing out location A's SIP trunk. The issues are: 1) The 911 centers knowing the real address a call came from irrespective of what actual number was used. 2) Can you route a number over a SIP trunk and have multiple addresses associated with that number?

Let's use real place-names to make it easier to follow, and we'll pick on the state of Pennsylvania....

Let's say my primary number is in Philadelphia (non-SIP), but that number is bridged to my second office in Pittsburg (SIP trunk). Let's say that I'm sitting in Pittsburg and make a 911 call with my Philadelphia number. When the call goes to Pittsburg 911, they need to know that even though its a Philadelphia number it CAME FROM the office at Pittsburg and help will arrive at the Pittsburg address.

How do I handle one DN having multiple addresses for proper 911 routing? If I port the Philly number over to Pittsburg SIP, will that break the 911 address association with the Philly address? When it comes to 911, do I really only have one location address per phone number, or can I have multiple addresses? Just remember - I'm only talking 2 locations here. What if a person has 5 or 6 offices they work from, but they have only one number?

That's my problem.

RE: Bridged numbers and 911 calls

Short answer. Yes you can do it.
The address of a 911 location send is attached to the 911 Caller ID you are sending to the PSAP. That database resides outside of your system.
You will need to work with AT&T (or any provider) and define 911 numbers for each location.
There is a service that major providers offer that you can have nationwide 911 out of SIP trunks. its an enterprise lever service.
Then the caller ID can be manipulated in the call manager and how the 911 calls present caller ID, but you will need that service in place first.
You can also implement Cisco Emergency Responder to better manage and control 911, but the service mentioned above is still required.

In any terms, you should be sending 911 calls out of the local trunks for simplicity. Since you only have two locations you shouldn't really need the above.
even with the same DN across both locations being shared, 911 can be send out different gateways if you use your css properly.

with centralized SIP that changes, and the emergency responder service becomes a must.

RE: Bridged numbers and 911 calls

Thanks whykap. I'm getting in touch with out AT&T rep to figure this one out.

RE: Bridged numbers and 911 calls

What I would do is create 911 patterns specifically for each site that broadcasts numbers associated with the correct address. This way it doesnt matter the DID or internal phone number or phone number mask for that matter. As long as the CSS is correct it will hit the correct RP and broadcast the correct number.

CCNA Voice

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