SUMMARY: Modem dial-back

From: Paul Hostrup-Jessen (smaug!
Date: Tue Dec 14 1993 - 05:14:02 CST

Hello Sun-gurus,

Last week I posted a question concerning dial-back software for modems. The
software should allow users to log in, identify themselves, get logged off
again and after a delay of at least a couple minutes get the modem to dial a valid phone number associated to the user's login.

I got an overwhelming response and the answer is: Yes, certainly you can
get this kind of software - both commercial and from Internet archives!

I have already ordered the "LAT TermServ" software via the European distributor
through our local Sun representative. The price is reasonable and I don't have time to do a lot of testing and configuring of scripts which might be able to
do the job.

However, here you have all my responses with many thanks to the following
(sorry if I left out anyone, mail kept coming in after I sent out the

Mike Raffety
Andy J. Stefancik
Dan Stromberg
Greg Potts
Armin Weber
Raymond Trzaska hou13us!
Gary Kremen
Roger Taylor
Doug Webber
Simon Goodfellow
Joseph S. Giroux
Andrew Scarman

Kind regards

Paul Hostrup-Jessen
System Administrator
Bruel & Kjaer A/S
DK-2850 Naerum

email: < ONLY valid email address !!

"Better yet, dial back on a *different* modem (phone line)!"

"There is a product called Termserv which has many security features which
we demo'd, but lost our budget before we were able to buy it. I can't
recall where to get it, but it was around $2,000."

"I haven't tried this out: comp.sources.misc
                             volume10 (Period: 6 January 90 - 6 March 90)
                             callback_hg/part[01-02] modem callback program

                             comp.sources.misc is archived in
                             among other sites."

"There is commercially available software called TermServ from Los Altos
Technologies which allows setting a variable to tell it how long to wait for
a modem to hangup. I have it installed here and tested to see if it was a delay
before trying to hangup, or a delay after hangup was initiated. It performed the
hangup immediately, and then waited the set time. The details of where you can
get the software follows:

Los Altos Technologies
346 Costello Court
Los Altos, CA 94024 (snail-mail)
(415) 988-4848 (main)
(415) 949-4825 (fax) (e-mail)"

"There is public domain software available which does the job, but I don't know where to get it. In Germany this software is sold by SUN Germany Consulting Division, tailored to SUN systems. If there will be no more help from the net
please ask me again, maybe we can get a copy of the software."

"LAT Product Description:

We make a dial-in firewall program called TermServ that allows users to
login, provide a password, and then TermServ hangs up the modem and calls
the user back. You can configure the amount of time that TermServ waits
before it calls back the user. There are multiple configuration options
available, so that there can be a single, multiple, or no callback numbers.
There are complete audit trails for the network administrator - you can
even "tap" a user so that everything that is echoed on the user's
terminal is recorded in a file. You can also restrict the time of day each
user can login, and the specific hosts they can rlogin into the network.

If you or anyone else finds this information to be useful, please let us
know. Perhaps our company should make this information available in a
permanent area on the Internet that everyone can access. TermServ is
used worldwide by Sun Microsystems. Here is a product description:

LAT TermServ (TM). LAT TermServ is a dial-in firewall program.
It guards access to an individual host, and can provide restricted access to
other hosts on the network. Features include dial-in passwords, callback
passwords, session tapping (the recording of a modem's input/output),
support for standard protocols (telnet , rlogin, Hayes, SLIP, PPP),
multiple session support (a user may rlogin or telnet to multiple
hosts during one call and use a "hotkey" to switch among hosts),
configurable lock-out (for users who exceed the maximum number of
failed login attempts), idle time-out detection, rich management reports,
no local host permissions, uucp dial-back and more. LAT TermServ
supports Sun SPARC systems running SunOS 4.x, HP
9000/300/400/700/800, SCO, and Pyramid. Prices start at $495 for an
expandable one port license.
To order, or to get more information, please call, fax, or e-mail us at
415/988-4848 (voice), 415/988-4860 (fax), or (e-mail).

"Your request for information on TermServ has been passed to us as the
European distributor.

TermServ provides the functionality you require for dialback, and provides more
securely than any other product. TermServ's largest user worldwide is Sun
themselves. Your Sun representative, when he dials in to check his email
is using TermServ. Please find attached information on TermServ.

Pricing is from 795 pounds for up to two modems.

Please contact Roger Taylor or myself of you have any questions or need
further information."

Best regards,


| Simon Goodfellow | 102 Green Lane | Phone: +44 (0)257 473199 |
| Sdirect Ltd. | Standish WN6 0TX | Fax: +44 (0)257 473014 |
| | UK | Email:|

"A scripting language called 'Expect' gives you the capability to create
responses built into a script which normally must be entered at a prompt. For
example, using Expect, you can change a password via a script or like you want,
dial back to a machine.

Expect is built using Tcl. Tcl is also a scripting language similar to Perl
(but is far more rebust if a GUI is needed). Both Tcl & Expect (you need Tcl to
build Expect) can be found at:
        /languages/tcl <-- tcl
        /languages/tcl/expect <-- expect

Before you download both, make sure you get compatible versions. I have tcl7.3
and as of yet, expect doesn't work with the newest tcl7.3. Expect does work with

Expect is very easy to learn and use. Unfortunately, I don't have any Expect
scripts to pass along to you, but if you're in need of Tcl scripts, then just
ask and I'll see what I can dig up for you."

This archive was generated by hypermail 2.1.2 : Fri Sep 28 2001 - 23:08:33 CDT