Re: making telnet secure

On Wed, 12 Nov 2008, Sudarshan Soma wrote:

Thanks Robert. I used port forwarding as a solution to secure telnet.
But now i am getting a problem in determining the source/client IP
address from which the telnet connection has originated. It always
shows source IP as as 127.0.0.1/localhost. Can anyone please suggest
me , if there is any way to determine the correct source IP.

That is accurate; the telnet daemon is receiving its connection from
"localhost", that is the same machine.

You probably need to rethink how your application identifies who the
clients are and where they come from. Relying on their IP address has
problems in many scenarios, not just this one, such as with Network
Address Translation. You can identify sessions by username, by a custom
TERM variable, by a terminal answerback prompt, etc.

Much will depend on the capabilities of the telnet client you are using.
Our clients (Anzio Lite and AnzioWin) can be queried for their local
machine name, their MAC address, their local IP address, and several other
identifying variables.

If you will explain how you need to use this information, I can offer
other suggestions. If this becomes unrelated to SSH, feel free to contact
me off-list.

Regards,
....Bob Rasmussen, President, Rasmussen Software, Inc.

personal e-mail: ras@xxxxxxxxx
company e-mail: rsi@xxxxxxxxx
voice: (US) 503-624-0360 (9:00-6:00 Pacific Time)
fax: (US) 503-624-0760
web: http://www.anzio.com
street address: Rasmussen Software, Inc.
10240 SW Nimbus, Suite L9
Portland, OR 97223 USA

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