Telnet vs SSH
Secure Shell, commonly known as SSH, and Telnet are two network protocols that have been used widely at one point in time or another. They are both used to connect to remote servers in order to facilitate some sort of communications. The primary difference, which also led to one superseding the other, is in security. SSH offers security mechanisms that protect the users against anyone with malicious intent while Telnet has no security measures whatsoever.
Telnet was designed to work within a private network and not across a public network where threats can appear. Because of this, all the data is transmitted in plain text, including passwords. This is a major security issue and the developers of SSH used encryptions to make it harder for other people to sniff the password and other relevant information. Telnet also omits another safety measure called authentication. This ensures that the source of the data is still the same device and not another computer. Without authentication, another person can intercept the communication and do what he wishes. This is also addressed in SSH as it uses a public key to authenticate the source of the data.
Due to the security measures that were necessary for SSH to be used in public networks, each packet contains less data to make room for the data of the security mechanisms. In order to transmit the same amount of data, you would need to take-up a lot more bandwidth. This is called overhead and was such a major issue back when internet speeds were very low because it translates to a performance hit.
The security issues of Telnet forced a lot of people to use SSH in order to protect themselves. It didn’t take a long time before SSH replaced Telnet in a great majority of its uses. Telnet did not fade away though as it is still used in some areas, mostly in testing and debugging. Telnet extensions were developed to provide security but they are not used in most Telnet implementations.
Summary:
1. SSH and Telnet commonly serves the same purpose
2. SSH is more secure compared to Telnet
3. SSH encrypts the data while Telnet sends data in plain text
4. SSH uses a public key for authentication while Telnet does not use any authentication
5. SSH adds a bit more overhead to the bandwidth compared to Telnet
6. Telnet has been all but replaced by SSH in almost all uses
- Difference Between Sony Cybershot S Series and W Series - December 22, 2012
- Difference Between Samsung Galaxy S3 and iPhone 5 - December 21, 2012
- Difference Between Samsung Galaxy S2 (Galaxy S II) and Galaxy S 4G - December 20, 2012
Thanks, that was a nice explanation. I used to use Telnet when in college I guess because it was within the network from the campus dorm or labs.
Now at work though we only exclusively use ssh.
Reply
Thanks
Reply
brilliant article
thanks
IT Damascus University
Reply
Great, thanks for the heads up!
Reply
Lovely summary.
1 additional question, can I expect SSH to act slower than Telnet?
especially on character inputs?
Reply
Yes ssh is slower than telenet as there are lots of overheads to provide security and authentication thereby reducingthe databits to be transmitted as compared to telenet
Reply
nice difference
Reply
Thanks
This is really needful info you have been provided.
Reply
Obviously, the industry seems to have gravitated to SSH, but several protocols, such as TN3270E and TN5250 still use TELNET as the underlying transport with SSL for the security layer.
So, what is wrong with TELNET over SSL?
Reply
I think as there is no Telnet installed on Linux, PuTTY is generally used to do the same thing: it’s a terminal that acts as if it was Telnet on Linux, but it speaks on SSH.
Reply
just the explanation i was looking for. nice.
Reply
Thanks for your explanation it is well digested
Reply
Great Article! Submitted a few years ago, but the information is still very valid. Thank you for putting this out there! 🙂
Found it via google
Reply
nice article it is very helpful
Reply
Thanks a lot for the neat and well explained article.
Reply
Yups, the explanation is clear. There is no different between SSH and Telnet, but SSH is more secure rather than Telnet. Thank you, found by google
Reply
thanks for this explanation.
Reply
excellent summary!!!
Reply
Wow this information helped me a lot…
Reply