Why SSH (Secure Shell) Exists

The most well-known application for remote management of a computer since the 1960's was Telnet. In fact, its popularity was such that even in the early 2000, there were network devices using Telnet for remote management.

The problem, however, was that Telnet had no encryption, meaning that anyone with a packet sniffer could intercept passwords or any information exchanged between two points.

SSH solved this exact problem. Tatu Ylonen, another Finnish figure in computer history, gave us the first version in 1995. He chose port 22 because it was between port 23 for Telnet and port 21 for FTP. SSH was using cryptography to secure the data transmission.

read more