This question is probably 20 years too late. I have a requirement where a bunch of analog phone lines will connect using dialup modem to my linux/windows server, in order to communicate. Just like we all did prior to broadband. This is for use in remote areas that don't have data connection. The termination on the server side will be ISDN E1. What is the modem hardware used by the ISPs to terminate the E1? I prefer not to demux the whole E1 into 30 analog lines and feed it to analog modems.

Will this work? https://www.dialogic.com/high-density-modems-e1-t1

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    That PRI card looks like it should work, but you need to talk to Dialogic.
    – Ignacio Vazquez-Abrams
    Commented Oct 5, 2017 at 6:32
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    You could probably very cheaply find some old Cisco gear that can do it. I had everything you needed several times over and threw it all out three years ago. Sorry.
    – David Schwartz
    Commented Oct 5, 2017 at 11:51
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    I remember now -- we used to use the Ascend Max line of products to do this. They're available used for practically nothing if you can find the exact model you need.
    – David Schwartz
    Commented Oct 5, 2017 at 12:07
  • Thanks for the tip. I'll look out for used boards then.
    – Sharath
    Commented Oct 6, 2017 at 5:58

1 Answer 1


You don't want to break an E1 (or T1) into individual lines because you will loose the ability to negotiate speed above 33.6k. Make sure the device you get handles analog connections.

USR gear did not play fast with other brands (mainly rockwell). Look at the following names in addition to Ascend Max

Cisco 5200 series Portmaster Paton 2960

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