OpenSSH

OpenSSH
SSH was re-implemented by the OpenBSD team, as there was one prevailing closed source version in use by most entitys interested in securing connections, but more commonly remote shells were achieved by known insecure protocols such as telnet, rlogin and rsh. With the goal of providing a BSD licensed, cryptographically sound replacement for those protocols, OpenSSH was born.

Authentication
Standard key exchanges are supported, for passwordless authentication, uid/password pairs are never transferred in the clear when password authentication is used, and kereberos authentication is also supported.

Encrypting methods
3DES, Blowfish, AES and arcfour.