What is SSH and How Does It Work?

SSH is a secured network protocol to access remote computers in a network.

Computers talk to each other through networks. Hence, network researchers defined a set of rules for communicating to other machines and started developing protocols like Telnet; using that, one user can take control over another computer.

But they are not secure, i.e., anyone in the middle of the network can intercept and read the data being transferred. In the mid-90s, a more secured protocol named ssh has been introduced as a reliable successor of telnet protocol.If you are a software developer or system administrator working in an industry, you might have used ssh, at least a single time. If you didn’t, let’s learn it now, as it is one of the must-know essential skills.
SSH or Secure Shell or Secure Socket Shell is a network protocol that helps us securely accessing and communicating with remote machines (mostly remote servers).

It provides strong encryption and is widely used by network administrators and developers to manage remote systems & applications, execute commands share files
SSH was created in 1995 to solve security issues faced by unsecured remote access protocols like rlogin rsh, Telnet

Now let’s talk about Telnet, which stands for Teletype Network developed in 1969. It is a simple command-line tool that runs on your computer to access a remote server (anywhere located in the globe). And send commands to be executed on that server, just as if you are sitting right before the remote server(even miles away from the server). Telnet transmits and receives messages in plain text over a network.

The commands you would execute could be to run programs, create directories, create/delete/transfer files, start/stop services, etc.

The problem with connecting another machine in a network is, the data being transmitted will pass through many networks. In the meantime, some of which might be insecure, and the transmitting data could be intercepted, possibly modified before it reaches the intended target machine.