SSH Protocol Runs on TCP port 22, initiated by client Client and server exchange banners at connect time: SSH-1.5-SoftwareName => SSH protocol v.1 SSH-2.0-SoftwareName => SSH protocol v.2 SSH-1.99-SoftwareName => both protocols SoftwareName is the implementation name and version Usually used for backwards (bug) compatibility Server always has a public/private key pair Public key is sent during connection setup Server's public key is cached by client to detect MITM