SSH

Problem

A server sits in a data center 1,000 km away. You need a command shell on it across an untrusted network. Sending commands and passwords in plaintext is unacceptable.

Solution — SSH

SSH establishes an authenticated encrypted connection.

Laptop
   ║ encrypted
Internet
   ║
Linux server

You can securely authenticate and operate the remote machine.

Core idea: SSH provides secure remote access over untrusted networks.