Windows

• PuTTY is an SSH1+SSH2 implementation. PSCP, an scp-style program for Windows, is also available.

  PuTTY is available under the MIT licence (BSD-like).

  "PuTTY is a free implementation of Telnet and SSH for Win32 platforms, written and maintained primarily by Simon Tatham, who lives in Great Britain."

• TTSSH (SSH1) is an SSH1-only implementation, by Robert O'Callahan.

  "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 to download and use and its source is available too, with an open source license. Furthermore, TTSSH has been developed entirely in Australia [...]."

  A variant UTF-8 TeraTerm Pro with TTSSH2 version is also available.

• Cygwin (POSIX software on top of Windows)

  OpenSSH (SSH1 and SSH2 protocol) with Cygwin can run on Windows using the portable version of OpenSSH, which can be either built from source or installed as a Cygwin native package. Several other packages of OpenSSH on Cygwin exist; one that is actively maintained is copssh.

• WinSCP

  WinSCP is a GUI sftp(1) and scp(1) client program for Windows. Its SSH protocol core is based on PuTTY.

• FileZilla

  FileZilla is a powerful FTP-client for Windows 9x, ME, NT4, 2000 and XP. It has been designed for ease of use and with support for as many features as possible, while still being fast and reliable. It supports SFTP.