WEIRD: telnet

Valentin Nechayev netch at
Sun Feb 13 16:23:18 GMT 2005

 Sun, Feb 13, 2005 at 16:38:18, atkielski.anthony wrote about "Re: WEIRD: telnet": 

>> 1. Telnet can use any ports providing the user redirects.
>> 2. Telnet passes clear text no matter what.
>> 3. ssh ought to be used to replace Telnet whenever possible.
>> 4. ssh also can be made to work with any port other then 22
> %ssh -p 21 localhost
> ssh: connect to host port 21: Connection refused
> %

If I show screenshot with ssh'ing to port 443, will it be convincing?
It is really production-using (there is a place where it is used to
pass overrestricted firewall thru proxy server with authorization).
Another department allows only connect to port 25 thru semi-secret SOCKS,
so port 25 is also working at some host as SSH.

> Telnet uses a protocol that is identical to many other protocols apart
> from the text of the messages exchanged.  SSH requires a specific
> handshaking sequence that other services on arbitrary ports do not
> support.  So if you want to test the SMTP port, or the POP3 port, or any
> one of quite a few other ports, you must use telnet.

Not current telnet, because it interprets 0xFF in wrong way. See bin/52032

> Since the original poster is trying to connect to port 61, I assume he
> is using telnet to test the service on that port, and so SSH is
> irrelevant.

It may be true or untrue. ;))


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