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postage loading machine (modem), does not work on the ATA187

FAX works fine on the ATA187, with T38. However the postage loading machine (modem), does not work on the ATA187. I use Port2 with Fax Passthrough configuration.

On the PSTN gateway I have the following config:

voice service voip

fax protocol t38 ls-redundancy 0 hs-redundancy 0 fallback none



modem passthrough nse codec g711alaw

With dial-peer debug and ISDN q931 debug, I can not see any calls coming from the ATA, so I guess there is something going wrong on the ATA.

I know the ATA186 can handle these analog modem machines for postage loading.

Here is configs on a ATA 186boxs that made it work, at the bottom below. However these settings are not available on the ATA187, the picture  below):


Cisco Employee

Re: postage loading machine (modem), does not work on the ATA187

It sounds like the call isn't routing properly?  What's the call signaling topology?  What VoIP protocol is the PSTN gateway using?  If you aren't seeing q931 output for the outbound call, the call either isn't making it to that gateway, or is failing on the voip leg before it hits the PRI.

I was about to say that the ATA187 doesn't support modem speeds, but I double-checked and the ATA configuration guide actually says that modem speed up to V.92 are supported:

I find this interesting, since that's a protocol based fax pasthrough switchover, which typically only supports faxes up to v.34.  Even modem passthrough on IOS gateways only is supported to v.34 speeds.  As far as I know, this is the only device which has ever claimed support for V.92 modems.  I suppose if you have one of these on each side, you should in theory be able to get near 56k modem speeds.

Do you know what modulation the modems are using?

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