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New Member

911 calls in campus enviroment ?

I have Set up a Call Managager 3.0(10). I have an T1 PSTN with 500 DID numbers. These numbers are spread out into 5 different Buildings. I would like to know if anyone had done this so that when a person call 911 the Dispatch center knows which building the 911 call came from. For example the first 100 numbers belong to building A, and the Second 100 numbers to Building B. I would like for the 911 service or caller ID. to reflect which building the call is coming from. Currently the 911 gets the main Pilot number of the T1 line .


Cisco Employee

Re: 911 calls in campus enviroment ?

Is it a T1 CAS (e.g. wink-start) circuit? If that is the case, there is no way to send caller ID information to the PSTN when you make a call, unless you are using Feature Group D which is pretty uncommon.

So if that is the case that you can't send caller ID information then the only number seen by the called party on the PSTN is the main number that the telco sends to them.

For Caller ID service to reflect the actual real DID numbers -- which can then be mapped to different buildings/locations for example -- then you would need a telephone circuit that supports your sending the caller ID information, such as ISDN PRI.

New Member

Re: 911 calls in campus enviroment ?

We ran into something similar when we first started our VoIP network. We found that SCC Communications, who is a clearinghouse for 911 registration for many of the CLEC's and ILEC's, couldn't work with us because we were not a CLEC.

We then worked through Bell South, and their PinPoint service, which allows us to register individual blocks of DID's to specific customer sites from our master blocks of DID's.

So everytime we bring up a new customer with our VoIP service, we register the block of DID's that we assigned to that customer to that customers site address. We could also get real critical and designate sub areas for that customer, like building number, floor, etc. per individual DID.


Tim Medley CCNP+Voice

Network Architect

VoIP Group


New Member

Re: 911 calls in campus enviroment ?

You are still going to have the problem with outgoing calls for 911 if you have a CAS-T1 that is not Feature Group D. If this is the case, the only way to do what you need is to set aside a set of channels specifically for 911 use for each facility and use Call Route Patterns on Callmanager in conjunction with Partitions to control which phones dial 911 out which channels on your T1's..

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