Modem Inactivity Timeout

In the properties of the Modem,
there is the possibility to define
a timeout: that a connection is
terminated automatically, if no
data (“idle“) has been transferred for a
predefined time (often used to ensure,
that a user does not forget to hang-up
and keeps the line occupied for HOURS)
This functionality is NOT executed
by the Operating system, but a feature
of the modem: the modem itself is
programmed to terminate the connection.

Modem connection (DUN/RAS) is terminating
You have either no idle-timeout defined or you have not yet reached the
timeout value, but the modem-connection is terminated by the system after
a very short time ?

the Event-Viewer Logs show the
details of the connection.
I had a case, where the connection
was always terminated after
approx. 1 minute.

I found the Microsoft Knowledge Base article Q164257:
Inactivity Timeout not Passed Through to TAPI Service Provider
There seems to be a “bug” in NT 4 workstation and server, that with
some(?) / all(?) modem-types the defined timeout value is not properly
programmed into the modem.
The Knowledge base article offers the workaround to switch-off the
timeout by editing the Registry under the key:

the Registry-key is usually “0000”, but when you had configured multiple
modems or changed to a different modem, it may be a different value
(like the “0002” in the example above)
The key for “InactivityTimeout” shows for my modem “S30=<#>
(for my modem, the S-register 30 controls the idle-timeout, it maybe a different S-register for your modem).

The article specifies:
“set the entry to the desired value”,
so I changed it to 250 (since the User’s manual for my
modem lists this s-Register to be programmed in Seconds)

My RAS-server does not terminate the connection quickly or unpredictable,
but now I have a new problem:
My RAS-server does not terminate the connection at all, regardless on
how long the connection has been idle !
(I will keep checking this. If somebody else has a solution, I appreciate to be informed).

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