Euro ISDN & Leading Zeroes

[Gordon Ross]

I'm unpicking some of the dustier corners of our CUCM setup and hit something I can't work out.

We've got some MGCP Euro ISDN-30 trunks. With Euro ISDN, the leading zero of the presentation number is not sent by the network. Yet when the presentation number is shown on the handset, the leading zero is there. I can't see anything in my configuration which adds it in, so it CUCM automagically adding in the leading zero?

Gordon.

[sudaggar]

are you getting leading zeros in calling number or called number for outbound calls?

run "debug isdn q931" on MGCP gateway and check if there is leading zeros been sent from CUCM.

If they are coming in from CUCM, check calling/called party transformation pattern CSS under gateway (outbound calls option under gateway config) or device pool configuration (assigned on MGCP gateway) in CUCM.

If there is CSS configured for calling/called party transformation pattern, check calling/called party transformation pattern in cucm (login CUCM Admin --> Call routing --> transformations --> Calling/called party transformation patter.

[Roger Kallberg]

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@Gordon Ross wrote:

Yet when the presentation number is shown on the handset, the leading zero is there. I can't see anything in my configuration which adds it in, so it CUCM automagically adding in the leading zero?

Gordon.

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No CUCM doesn’t add anything by magic. Anything added comes from configuration deliberately put into the system. Likely it would be transformation patterns.

[Gordon Ross]

I finally found the answer: It's one of those hidden/advanced Service Parameters: