TTSSH is a free SSH client for Windows. It is implemented as an extension DLL for Teraterm Pro. Teraterm Pro is a superb free terminal emulator/telnet client for Windows, and its source is available. TTSSH adds SSH capabilities to Teraterm Pro without sacrificing any of Teraterm's existing functionality. TTSSH is also free and its source is available too. Furthermore, TTSSH has been developed entirely in Australia, and can be exported from here to anywhere in the world (apart from places where people aren't allowed to own cryptographic software at all :-( ).

To be more precise, the current version of TTSSH (1.4) includes the following features:

* Compatible with SSH protocol version 1.5
* Ciphers: 3DES, IDEA, Blowfish, DES, RC4
* Server authentication using the ssh_known_hosts database (including the option of adding a server's key to the database)
* Authentication using password, RSA, rhosts and rhosts+RSA
* Compression support
* Connection forwarding, including full support for X connection forwarding

Note that TTSSH is just an SSH client and does not include any other SSH tools (scp, ssh-keygen, ssh-agent, etc). Furthermore, because it's tied into Teraterm, it's only suitable for interactive use. For non-interactive uses such as interprocess communication, you want a straight port of the Unix client.

http://www.tunl.duke.edu/~canon/Help/ttssh.html