911 Dialing is Slow

[Bob_IA]

Good day all,

          I'm working on an issue with our CUCM (11.5.1) where the time between when a user dials 911 and when the user hears it ring through is 7 seconds on a model 7945 phone.  The route pattern for 911 and 9.911 both are set to "Provide Outside Dialtone" and "Urgent Priority", to supersede the Interdigit timeout (T302) default of 15000ms.  Our dial-outside pattern is the default 9-1-XXX-XXXX which takes about 2 seconds before one hears the ring-through to normal number.

Are there other places that I can look to check or a troubleshooting item that I'm not aware of?  I'm new to the CM world, so I appreciate any advice.

Thanks,

Bob

[davisjaron]

Just as a starting point, ensure the partition with your 911 route pattern is at the top of the list in your calling search space.  The list is chronological, so if you have a 9.@ in a partition ordered higher in the CSS, it will continue to wait for the rest of the digits.

[Bob_IA]

Thanks davisjaron.  Looking in the search space, 911 is down the list.  I'll get that brought up top.  I won't test it today as there is snow in our region and the dispatch center will be busy, but I will test it out on Monday.

[George Sotiropoulos]

You may also need to check via the Dialled Number Analyzer to check if there are any other -overlapping-  Route Patterns (via Alternative Routes) that may affect the time that is required to dial-out.

George

[Chris Deren]

@davisjaron

 That is not correct, the order of partitions in a CSS is only significant when there are 2 exact patterns and serves as tie-breaker.  If there are 2 possible matches in 2 different partitions the order is irrelevant as CUCM will always pick the more explicit match.  So, if you have pattern 9.@ in PT1 and 911 in PT2 where PT1 is listed first, the 911 pattern will ALWAYS be selected even though it's partition was listed below PT1.

To answer the original question, if dialing 911 results in latency, it's most likely due to overlapping dial plan where another pattern longer than 911 is also a potential match and CUCM is waiting through interdigit timeout before proceeding with the call.  Review your dial plan for potential overlaps, i.e. anything using wildcars such as XXXX, [2-9]XXX.., etc, etc.

[Bob_IA · Accepted solution]

I apologize for taking so long.

I recently figured out that our 911 dialing goes through a 2911 gateway to an analog line at the building location. Turns out the interdigit timeout for that dial pattern is controlled there, and had to lower the IDT for that line.

Sorry again for the time it took, and thank you for the advice!