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New Member

Modem over IP speed

I am testing modem over IP using the modem passthrough feature across 3662 and 2651 gateways. The setup is fxo/fxs. It works fine except that the maximum connection speed is typically 14.4kbps, and very very rarely 19.2kbps.

Is it possble to get a higher dial-up speed over IP on Cisco platforms? Cisco says the modem passthrough feature supports modem speeds up to V90!


Cisco Employee

Re: Modem over IP speed

Modem passthrough will support v.90 modems but you won't get near max speed out of them. You may get better results with the modem relay feature:

Hope this helps

New Member

Re: Modem over IP speed

Issues here are Codec related.for decent modem performance,Pass through is very bandwidth thirsty. Have you tried remoting your modem ?

i.e your terminal is one side of your wan and simply place the "local" modem at the far end of the link ?

then you only need create an async' link between the two end points. Modems will conect as fast as train sequence permits - and the data exchange is governed by your WAM and business limitations allow. One idea which works. Good Luck !

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