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Community Member

ATA 188 and faxing

Can someone please provide me a clear and concise way of configuring an ATA 188 to reliable do faxing? What protocol should I be using to best register with the CM and do this? I am on the latest version of CM and ATA code (SCCP). I just want to send/receive faxes to/from the average fax machine on B1 and Centrex lines.

Currently the default settings on the ATA give me about 70% success rate. The rest get cut off, smeared, or lines are cut-off in the middle.

Wouldn't be that big of a deal except this is a doctors office.




Re: ATA 188 and faxing

have a look here for starters -

What is your main PSTN gateway ? Check for clock slips on the T1/E1 if this is what you are using - these will kill fax calls in the way you have described.

Community Member

Re: ATA 188 and faxing

You can also try forcing the fax machine to a lower baud rate. Some newer fax machines can negotiate up to 33.6K, but the ATAs will only support up to 14.4K under ideal circumstances. FXS in a router will do a much better job with the higher baud rates.

Here's the product data sheet and a quote from it below:

"Success of fax transmissions up to 14.4 kbps depends on network conditions and fax modem/fax machine tolerance to those conditions. Network must have reasonably low network jitter, network delay, and packet loss rate."

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