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USR 56 Fax Modem Fails to As5400 Nextport Modems

I have cut over an 800 # to my As5400's and a some users with USR 56k Fax modems can not negotiate a connect. Does anyone know of any possible fixes either to USR modem or As5400.

I have set modemcap on AS5400 to S29=6 to skip V.92. It appears I have the same problem if these USR modems dial an As5300 with Mica modems also.

Need some recommendations to try


Re: USR 56 Fax Modem Fails to As5400 Nextport Modems

When implementing Store and Forward Fax on a modem card, the off-ramp gateway does not necessarily need to have MMoIP dial peers configured to establish connectivity with the receiving fax device; therefore, off-ramp MMoIP dial peers are optional when using a modem card. You basically use off-ramp MMoIP dial peers if you need to specify a particular resolution for the fax transmission or if you need to define an encoding type. For example, it might suit your company's needs to send the fax-mail using the least definition as possible to save network resources. In that case, you might want to define a higher image resolution using an off-ramp MMoIP dial peer. Another case where you might want to use an MMoIP dial peer would be if the fax devices in your network could only process a particular type of encoding or compression. If you do decide to configure a MMoIP dial peer, be sure to match the incoming called number command value with the destination pattern telephone number you configured for the corresponding on-ramp POTS dial peer.

Cisco Employee

Re: USR 56 Fax Modem Fails to As5400 Nextport Modems

The only general problem that I know of with these USR modems was the bug when they first came out with V.92 - but turning off V.92 should have worked around this problem. (Are you SURE that the S29=6 is taking?)

You might test with +PIG=1 on the client (see just to make sure.

Beyond this, the only thing I would try is detuning the USRs. I.e. try disabling V.90 on them; try capping V.34 at 28800 bps; disable V.34 and try V.32bis; etc.

Good luck,