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DS3 for Voice and Data

A customer is looking for moving his T1s into a DS3. Currently he has 4 T1s for data and 2 T1s for voice. They are planning to remove all T1s and move on to a single DS3 pipe. Some channels for data and some channels for voice. Anybody who has implemented something like this, please throw in your experiences.

FYI, the router being used would be a 3640 with a NM-1A-T3 module. Also this is an IP Telephony environment. So the 3640 will be a gateway for IP Phones to make calls to PSTN.

Any information is appreciated.


Re: DS3 for Voice and Data

Ive seen this topology before (same routers). Its pretty straigh forward, just make sure you have LLQ configured for your voice traffic.

Not sure if that is a full T3 or fractional, but if you plan on going over 25mb or so, you should consider using a 37xx instead.

Re: DS3 for Voice and Data


Note that the voice traffic is not VoIP, but traditional PSTN calls.

Also see this post

Also I opened a case with Cisco, and TAC also confirmed that its not possible to use the NM-1A-T3 card for terminating voice calls from PSTN. Also unlike the NM-HDV module, the NM-1A-T3 cannot take DSP chips.(farms)

Any suggestions ?


Re: DS3 for Voice and Data

Yea, the TAC is right. I beleive the AS5400 will be able to do this, it has a T3 card and DSP's for voice.

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