911 Caller ID Problem

Unanswered Question
Aug 25th, 2010

I have what I consider a strange problem.  When one of our sites calls 911, 911 sees the wrong caller ID from the number we dialed out on.  As a result, we keep receiving an adjacent county's 911 services.  My Cisco administrator tells me that she's masked the caller ID correctly in CallManager, but our PSTN provider is saying that the caller ID is changed between their equipment and 911 which to them points to the CallManager.  Is there a sepearate place to configure caller ID for 911 in CallManager?  I'm not sure of the dot release, but we are on version 7.  Thanks! 

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Aaron Harrison Wed, 08/25/2010 - 09:13


I've never seen an install where you have to modify anything for 911. Assuming you are presenting the numbers in a way that works when you dial elsewhere, and that you are sending the calls out the correct circuit, all should be OK.

You can only control what's sent out, and if the service provider can't tell you what you are doing wrong (and it works OK when you dial out to your mobile or other destinations) then the problem is with them or somewhere else further out of your control.

So in short - get them to tell you what you are doing wrong, and if you're not doing something wrong they need to investigate further.


Kirk Gable Wed, 08/25/2010 - 09:44

Thanks Aaron.  I tend to agree, as my administrator is quite certain there is nothing more she can do.  And yes, when you call another number (not 911), the mask displays correctly.  Windstream (my carrier) claims there is a seperate place to administer 911, but I'm guessing that you disagree with that? 

David Hailey Wed, 08/25/2010 - 09:52


Out of curiousity, is this a 911 call that is being routed from a remote location thru centralized trunks?  Also, is the user calling from a DID outside of the numbers associated with the trunk(s) the call would be routed out of?  Lastly, does the user have a DID or an internal (software number)?


Kirk Gable Wed, 08/25/2010 - 10:10

The site is using a PRI for both inbound and outbound calls that is terminiated across the street at another location.  And yes, the user has a DID, but it is in a range of numbers associated with the PRI.  The setup is really nothing special.    

David Hailey Wed, 08/25/2010 - 10:18

In that case, I'd have to go with Aaron (and your hunch as well). Have to figure a way to push the Telco into actually showing you wherein the problem lies. Sorry I couldn't be of any further assistance, my friend.


Aaron Harrison Wed, 08/25/2010 - 10:19


No - there's no special config required generally... as David pointed out; as long as you are sending the call out a sensible (local) location and aren't trying to send any odd numbering out there should be no issue. Even if you are sending out random numbers the SP should override it with a sensible default (e.g. the main number of the circuit).



Brandon Svec Wed, 08/25/2010 - 11:16

In my experience with PRI in the US the 911 operator will often see the BTN as opposed to (or maybe in additon to) the number I have programmed my system to send.  In most cases with a new circuit the CLEC has not yet provided this information to the PSAP database.  In many cases when I test a new install the DID numbers have not been submitted yet either.  This results in the 911 operator stating they have no information on my location.  This usually resolves itself after a couple days.

I have a funny story that happened to me yesterday.  In 20 years of installing CPE I often test 911 on new installs or by customer request.  I simply dial 911 and when they answer I immediately state that this in *not* an emergency and that I am a phone installer testing 911 dialing.  I tell them the address and phone number and they will tell me if it matches their screen or not.  I have never had a problem and the dispatchers have always told me if the information matches or not.

Yesterday, for the first time, the operator responded by saying she was required to send emergency services anyhow.  I told her to please not to as I just stated that this is *not* an emergency and I am simply testing the line.  She claimed it was policy and that she would have to dispatch anyhow.  I told her to please note that I requested this not be done.  I waited 15 minutes before leaving the site and no one showed up.  I need to follow up today to see if they ever came or not.

Kirk Gable Wed, 08/25/2010 - 13:09

I appreciate everyone's responses so far, but I have an update.  I spoke with the Telco and they ran a trace on the circuit and confirmed that they are getting the wrong caller ID from the CPE, which is our Cisco system.  Is there another place in CallManager that one can set the caller ID besides at the station itself?  Thanks!

afmmanicke Wed, 08/25/2010 - 14:29

If you do a debug isdn q931 and ter mon on the gateway you can watch the call exit your system.   Also I'd look at the route pattern.   I'm guessing you have a 911 route pattern set up so it can route the call with urgent priority.   Be sure nothing too special is set up on the Calling Party Transformations.

Kirk Gable Thu, 08/26/2010 - 05:05

I will suggest that my admin run that debug and also check the route pattern.  We had a new site go up yesterday and during 911 testing the caller ID came up wrong again.  So I'm eager to find out what the issue is if it's in our system which the Telco is convinced it is. 

philip.e.denton Thu, 08/26/2010 - 10:56

The previous poster is right about running a debug isdn q931 to verify what's leaving your gateway (assuming you have PRI(s)).  It will definitively tell you what the carrier is getting from you.

If your q931 debug shows the right digits it's the carrier's fault.  All the way.

If they're getting incorrect digits from you I'd first run DNA from one of the offending phones to watch how CUCM is manipulating digits up until the call hits your gateway.  After verifying the calling number is correct up until the call leaves CUCM I would double-check the dial plan in your gateway (specifically dial-peers related to 911 and any associated translation rules/profiles) and look for unexpected digit manipulation changing the digits of your call after it's left CUCM but before it his the outbound PRI.


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