I need to find an Access Server suitable for the following application:

A terminal dials in to the access server, which then establishes a TCP 
connection to a host. The serial (i.e. asynchronous) data stream from the 
terminal is then forwarded over the TCP connection, and the TCP data stream 
from the host forwarded over the dial-up serial link to the terminal.

I believe Cisco Access Servers support this sort of application as standard, 
and it can be configured by use of  "autocommand telnet".

What I don't know is which particular model numbers would be most suitable - 
the Access Server needs to support Primary Rate ISDN (E1). In addition, 
another Access Server is required to support a pool of PSTN lines for backup 
purposes.

Can anyone help?

Thanks very much,

Jonathan Goodchild

In article <42fb2a14$0$146$7b0f0fd3@mistral.news.newnet.co.uk>,
Jonathan Goodchild <jon.goodchild@no-spam.jgoodchild.com> wrote:
:I need to find an Access Server suitable for the following application:

:A terminal dials in to the access server, which then establishes a TCP 
:connection to a host.

Your posting spurred me to remember a brand name for these kind of
devices that I'd been trying to think of : Gandalf, from Gandalf Data Ltd.
now apparently part of Mitel. Unfortunately the relevant products appear
to have been discontinued, but you might be able to find some on the
used market, If my recollection is correct, they were never "exciting"
devices but they were real work-horses. It appears that Gandalf made
at least one such box for interface with ISDN.

:The serial (i.e. asynchronous) data stream from the 
:terminal is then forwarded over the TCP connection, and the TCP data stream 
:from the host forwarded over the dial-up serial link to the terminal.

I have been (when I have spare time!) investigating devices that
are similar, only used in reverse: "serial to ethernet convertors".
My application is a need to drop an ethernet device somewhere and
connect to it remotely so as to be able to talk to a remote serial
port. I have found quite a number of such devices, with a *big* price
spread. I have encountered models with 1, 2, 8, 16, and 32 ports,
and models that were expandable in groups of 32 up to at least 228
if I recall correctly. I have also encountered Windows software
designed to grant remote control over serial ports -- not useful for -my-
purpose, as I don't want to drop a full computer out there, but
possibly useful in your situation.

Some of the devices I have found allow ssh or ssl connections.


Probably the main difference compared to an "access server" would be
in the authentication mechanisms available, and in matters such as
detecting dead lines, or timeouts, and in ability to control modems via
chat scripts; I would not expect advanced features from the lower end
"convertors". Sometimes advanced features are not needed, though.
-- 
  "Never install telephone wiring during a lightning storm." -- Linksys

On Thu, 11 Aug 2005 12:07:07 +0100, "Jonathan Goodchild" <jon.goodchild@no-spam.jgoodchild.com> wrote:

~ I need to find an Access Server suitable for the following application:
~ 
~ A terminal dials in to the access server, which then establishes a TCP 
~ connection to a host. The serial (i.e. asynchronous) data stream from the 
~ terminal is then forwarded over the TCP connection, and the TCP data stream 
~ from the host forwarded over the dial-up serial link to the terminal.
~ 
~ I believe Cisco Access Servers support this sort of application as standard, 
~ and it can be configured by use of  "autocommand telnet".

Yep.  Use "autocommand telnet <host> /stream" to use raw TCP (aka
"TCP clear") rather than telnet.

~ 
~ What I don't know is which particular model numbers would be most suitable - 
~ the Access Server needs to support Primary Rate ISDN (E1). In addition, 
~ another Access Server is required to support a pool of PSTN lines for backup 
~ purposes.
~ 
~ Can anyone help?

For systems with digital modems, I'd recommend an AS5350 or AS5400.
Or you can use 3600/3700/3800 series router with NM-*CE1* and NM-*DM*.

For a system with analog modems, I'd recommand a 26/28/36/37/3800
series router with NM-*AM-V2 or WIC-*AM in it.

Regards,

Aaron