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Modem Passthrough on 3660?

Unanswered Question
Dec 12th, 2001
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I'm trying to connect analog modems to FXS ports on a 3600 which routes the call out a T1. I can only get 22k connections and even those are pretty shaky. Faxes work fine going through the FXS ports.


Does the 3660 support modem pass-through? What do I need to do to enable this? Right now, the 3600 is serving as an H323 gateway to CM 3.0.


We also have a VG-248 on order. Will that support analog modems?


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paul.harrison Thu, 12/13/2001 - 14:02
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NOOOOOOOOO!


Do NOT do it.


There are BIG BIG problems trying to do hairpinning on the same box. I went through massive headaches about 4 months ago trying to get fax calls coming in on an E1 on a cat4K AGm to terminate on an FXS port on the same blade, in the end Cisco TAC loaned me an AS5300 (talk about sledge hammer to crack a nut but I ain't complaining) and that fixed the problem.


If you have FXS ports on a seperate box then use them (the VG-248). It seems the boxes can cope with jitter over IP and compensate accordingly, but not over their own back planes.


Paul

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