Calling Party Transformation overwriting ELIN from CER

[Bill]

I have seen this with CUCM/CER 11.5 and 12.5.

This is when using Calling Party Transformations to change 4-digit internal extensions into valid 10-digit numbers for outbound calls.

The Transformation is applied at the gateway using the Calling Party Transformation CSS.

For 911 calls, CER is setting the proper ELIN, but the Transformation is overwriting it, because the gateway sees the 4 digit Calling Party, and transforms it.

Anyone know a fix for this? (Other than not using Transformations)

Thanks

[Roger Kallberg]

If the match statement on the calling transformation matches the number set as the ELIN this is expected. If you do not want it to be changed by the transformation you’ll have to change the match statement to not match.

[Bill]

Thanks for the response.

The Transformation is not matching the ELIN number from CER, it is matching the 4-digit DN of the phone that made the 911 call.

The Transformation is set to match 6606, and prefix 860555, so the Caller ID is 8605556606.

This works for regular calls.

For 911, CER is setting the ELIN to 2079110000.

(this is in a lab environment, so not real numbers being used)

But when DN 6606 dials 911, the call is seen as 8605556606, even though the ELIN from CER is set to 2079110000

If I dial 911 from a different DN that does not match the Transformation, the ELIN is sent out correctly.

[tomattreau]

Were you able to solve this issue?  I am experiencing the same symptom.

[Roger Kallberg]

AFAIK you cannot use transformation in combination with CER as the transformation takes precedence over the modification that CER does. You’d need to look at other options for changing the calling number than transformations. I’d recommend use of translation rules in your voice gateway(s).

[Kaloyan Botev]

I suggest that you get rid of the transformations on the gateway. Most people use external phone number masks applied on the phone lines to ensure the correct external numbers are presented to the PSTN.