Comparison of PING,TELNET,SSH commands under Linux

Ping works on the third layer of the OSI model, the network layer .

It is mainly used to test whether the network reaching the destination host is connected and cannot detect whether a port is open.

Ping uses the ICMP protocol and does not use a specific port.

You can also ping the domain name, so that you can directly see the IP address of the domain

SSH is similar to Telnet, which is a remote login tool.

SSH is divided into two parts: Server side and Client

The server side is a daemon that processes client connection requests, typically sshd

clients include SSH programs and other applications such as Scp,slogin,sftp

The biggest difference between them is that SSH is encrypted for transmission , security is high, Telnet is used in clear text transmission , less secure.

Tables are available to represent major differences (originating from Https://techdifferences.com/difference-between-telnet-and-ssh.html#Definition):

BASIS for COMPARISON	TELNET	SSH
Security	Less secured	Highly secured
Uses Port number	23	22
Data format	Telnet sends the data in plain text.	Encrypted format is used to send data and also uses a secure channel.
Authentication	No privileges is provided for users authentication.	Uses public key encryption for authentication.
Suitability of the network	Private Networks is recommended.	Suitable for public networks.
Vulnerabilities	Vulnerable to security attacks.	SSH has overcome many security issues of Telnet.
Bandwidth Usage	Low	High

In addition, Telnet can test whether a port on a remote host is open , and the command is:

Telnet Ip/domain Port

Comparison of PING,TELNET,SSH commands under Linux