Votes: 0Posted On: Feb 20, 2018 04:46:40
SSH and Telnet are both network protocols used to connect to a remote host. Between the two, Telnet is a much older protocol and was used to connect to primitive routers and servers. SSH or Secure Shell is a more secure way to connect to a remote host. Here are some comparisons between the two.
Telnet was developed in 1969 with the purpose of connecting to remote hosts. It uses Port 23 to carry out communication with the remote host. However, Telnet could be used mostly to transfer basic information as the communication was not encrypted and was comprehended very easily.
SSH was developed in 1995 with the aim to provide a secure way of communication between the local and remote hosts. It uses Port 22 to carry out communication with the remote host. SSH or Secure Shell, as the name suggests, introduced the concept of data encryption. SSH uses encrypted keys that are possessed by the local and the remote hosts. If anybody tries to hack into the communication, it is not possible for the hacker to interpret the communication as it is in encrypted form.
The main and the most important difference between the two protocols, Telnet and SSH, is data encryption.
Telnet communicates with the remote host through plain text including username and password. Using any network trace tool like Wireshark, the data can be read and comprehended as it is in simple plain text. Once the username and password are attained, the hacker can access the server anytime.
SSH, however, uses encryption keys that create a secure connection between the local and remote host. Encryption keys are basically alphanumeric codes that are possessed only by the two communicating hosts. The encryption key pair comprises of a public key and a private key. The public key is stored in the host(s) that you want to access remotely. Private key is stored on your local host and is used to access the public key. When you try to ssh to a remote host, the remote host sends you the public key and tries to authenticate you. Since you have the private key, the remote host identifies you and a secure SSH connection is set up.
Which one is better?
There are no points for guessing that SSh is a much better and superior way of communicating with remote hosts. The data, when analyzed with the help of a network tracing tools is in the form of random alphabets and letters that makes no sense to a hacker trying to break into the ssh connection. However, with Telnet, the data is in the form of an plain text that can be read by anyone.
The only argument that can be made in the favour of telnet is that it takes less CPU capacity because the system does not have to encrypt or decrypt data. But to be frank, it is not even a factor as the CPU capacity needed is negligible.
To summarize, I would use SSH over Telenet 99 percent of the time as it is swift, secure and a great way to connect to many remote hosts with the same key.