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Configuration for converting PRI to SIP on 2911 Gateway

I have a client who is slowly migrating to a Cisco UC environment, but is only willing to upgrade certain pieces of infrastructure at this time. I'm looking for assistance with configuring a Cisco 2911 to convert a T1/PRI connection to SIP for a handoff to Microsoft Exchange. The general "diagram" is listed below.

Voicemail<- - - - - -> MS Exchange 2010 < - - - - - SIP - - - - - > Cisco 2911 < - - - - - PRI/T1 - - - - - -> Nortel PBX<- - - - - - >PSTN

At this time, I am only concerned about the Cisco 2911 configuration. The PBX will provide a T1/PRI connection, and MS Exchange will have a dedicated IP address.

Any help is appreciated.

VIP Super Bronze

Re: Configuration for converting PRI to SIP on 2911 Gateway

This is actually pretty simple. You do not need to configure CUBE or the SIP UA for this as it can be done just with a few dial peers.

The incoming VoIP dial peer would look like this:
dial-peer voice 2 voip
description INCOMING VoIP
voice-class codec 1
session protocol sipv2
session transport tcp
incoming called-number .
dtmf-relay rtp-nte
no vad

The VoIP dial peer to Exchange would look similar to this:

dial-peer voice 10 voip

description OUTGOING to Exchange


monitor probe icmp-ping   <-- Optional; takes the dial-peer down if Exchange stops responding.

voice-class codec 1

session protocol sipv2

session target ipv4:

session transport tcp

dtmf-relay rtp-nte

no vad

And of course you would need the dial-peer appropriate for the POTS side. IOS interops between SIP and ISDN quite well.
The only thing I have not tested is how ISDN RDNIS would map to the Diversion header on SIP.

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