What is special or different about telnet ???
 

What is special or different about telnet ???

Can you elaborate the question a bit more? To tell you what's different about telnet, I need to know the other member of the comparison (telnet vs. _________).

Telnet is just another protocol to connect two remote computers.

like difference between telnet & ftp and also between telnet & tcp

telnet is a terminal server/client arrangement, like ssh except its unencrypted, so easy to spy. Do not use it.
ftp = File Txfr Protocol
tcp = Transmission Ctrl Protocol.

You should read up on these in wikipedia.

They are unrelated thing.

TCP is a more low level protocol, higher level protocols, like http, ftp or even ssh make instensive use of TCP.

Telnet is a terminal protocol, just like someone above said: don't use it. It's old and not reliable. Use ssh instead.

FTP is a protocol to transfer files between remote computers.

There are lots of docs around in the net explaining the different network protocols at many levels, the wiki is also useful for an initial review so you can get an idea where your research is heading.

sounds like homework. Please be more specific with your question if it isn't.

Thanks everyone....
The general thing about TELNET is something i'm aware of and know...
Wanted to know, how TELNET's different from other protocols...

Well, each protocol has a different specification and works on a different way.

It's like asking the differences between the yellow and the green colors.

A good place to start is to read the RFC's for each protocol, use the search box on this site to search for the different protocols:

http://www.faqs.org/rfcs/

The only use for telnet i can think of is to play MUD games!

Telnet is rather primitive yes, but it has its uses. In embedded systems, where size is important, telnet is a useful alternative to ssh, which would be prohibitively large. Of course, in these places you also see things like xmodem and tftp.

On PC's tho, yea, telnet is a rather inferior alternative to ssh.

No sir. Telnet was clearly designed for nethack. MUDs phfsssh.

=0)

What about the security in TELNET ?

That depends on the meaning of your question.

If you want to know what security measures does TELNET implement: none at all. The protocol is as plain and transparent as it can be.

If you mean "how to harden it", then I can't help. I never bothered really. There are better protocols around.

I consider it useful only for local stuff, overall when you need to connect to do fix something. It's useful to fix routers and things like that. I also use it sometimes to connect to mldonkey on my LAN server :p

Telnet is essentially obsolete at this point. Many (all?) distros do not even come with a telnet server installed. Telnet has been replaced with SSH. Where as all data passed between client and server with telnet is plain-text, I.E. readable from any one able to capture the packets; all SSH data is encrypted.

Similarly FTP is obsoleted by SFTP which uses the same SSH encryption with File Transfer Protocol on top.

how to enable and disable TELNET in RHEL4?