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Seeking help\advice setting up a voice T1 when used to PRI (CUCM 7.1)

I’m having trouble finding the documentation I’m looking for, so I’m wondering if anyone here can help me.  Forgive me if I have my terminology wrong. 

Soon I’ll be setting up a small (27 phones, a few faxes) remote site onto my existing CUCM 7.1 cluster.  The catch is that this site’s PSTN connection (for 3-4 weeks anyway) is a T1, not a PRI. 

I have setup many locations with MGCP and PRIs, and don’t have much trouble, but I’ve never setup a site that uses a “Digital Access T1” before.

The phone company has given me the Line coding (AMI) and framing (SF), and the channels that are in use (1-4, 13, 15-17).

There is a 100 number DID block assigned to this T1, but only 16 or so of the numbers are in use.

I use MGCP for the gateway, and setup SCCP media recourses on the router that are setup to media resource group lists in CUCM.

Normally I would setup a translation pattern to translate the incoming 7-digit number to our 5-digit extension, but it doesn’t appear to work the same way with a channelized voice t1.

I’m hoping someone has a router config example, maybe some CUCM examples that might give me more insight to configure CUCM using a voice T1 when I’m used to using a PRI.  Links are welcome!

I’ll be using a Cisco 2821 router with VWIC2-2MFT-T1/E1 in Serial0/2/0:23.

Thank you.

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Re: Seeking help\advice setting up a voice T1 when used to PRI (

For you description, seems like the circuit will be upgraded to PRI in 3-4 weeks.

Since MGCP (among other limitations) doesn't support partial PRI, I would recommend you configure this as H.323 or SIP GW.

This way, when upgraded to PRI, you will have no change on the CM, and just reconfigure the GW.

You will also have a much more robust and flexible configuration.

For further discussion please use UC forum, IP Telephony, not Service Provider.

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Re: Seeking help\advice setting up a voice T1 when used to PRI (

Sorry, I didn't realize I was in the service providers.

When the PRI gets installed, it will be on a different router, so I'll have a new configuration either way.  Again, I'm not looking for PRI help, just wondering if someone has TIPS or "gotchas" when using a T1.

For what it's worth, I use several partial PRIs with CUCM with no issue.  This is the first time hearing it's not supported.  I've been using partial PRIs with MGCP since CUCM 3.x with no issues.

Thanks for your reply!

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