SSH for Unix (including MacOS X)
SSH Tectia by SSH Communications Security, Ltd.'s (Tatu Ylönen) fully proprietary and commercial SSH1/SSH2 client & server successor to Ylönen's original SSH 1.x reference implementation including scp, which (the latter) was issued under a free-software licence through v. 1.2.12, and then a mostly-free licence through its latter (1.2.13 through 1.2.27) versions, and then a gratis for non-commercial use licence starting with 1.2.28 that added SSH2, sftp2, & sftp-server2, among other things, and gave access to sounce code. Original implementation was terminated at v. 3.2.9. SSH Tectia drops source code access and gratis non-commercial usage. ssh protocol v. 2.0 & 1.5.
F-Secure by F-Secure Corporation (formerly Data Fellows, Ltd.) is a proprietary SSH client & server. Includes scp. Until early 2000, F-Secure sold licensed variant versions of SSH Communications Security, Ltd.'s (Tatu Ylönen's) software. Presumably, future versions will now diverge from Ylönen's. Client: ssh protocol v. 2.0. Server: ssh protocol v. 2.0 or 1.5 (separate products).
Portable OpenSSH by The OpenBSD Foundation is an SSH client & server. Source & binaries under the BSD licence. Includes Kerberos v. 4 support. Forwards Kerberos & AFS tickets. Forked and updated from Ylönen's v. 1.2.12, with all encumbered, non-free, and copyleft components replaced. Includes scp. ssh protocol v. 2.0 & 1.5
Dropbear by Matt Johnston is a small SSH2 client & server, primarily but not exclusively intended for embedded use. Source & binaries under an MIT/X11 licence. Supports X11 forwarding, and authentication-agent forwardingfor OpenSSH clients. Includes scp and other traditional SSH functions. ssh protocol v. 2.0
LSH by Niels Möller's is an SSH client & server. Currently still lacks ssh-agent and ssh-add. Includes SRP for key-exchange. C and Scheme source code only, under the GNU General Public Licence. ssh protocol v. 2.0.
ossh by Björn Grönvall is an SSH client & server, created as a free-software fork & update of Ylönen's SSH v. 1.2.12. Source only, issued under the original (free-software) Ylönen SSH v. 1.2.12 licence. ssh protocol v. 1.5.
[gone from ftp://ftp.zedz.net/pub/crypto/ssh/ossh/]
FreSSH by The FreSSH Project (Thor Lancelot Simon's and Eric Haszlakiewicz) is an SSH client & server, issued under the BSD licence. ssh protocol v. 1.5.
AppGate by AppGate (Martin Forssen) is an SSH client & Server. Proprietary. Server is for Sun Solaris 2.6+ (SPARC or x86). Client is for any Unix, via provided source code. Authentication methods include ACE/SecurID, Entrust, iD2, and Telia EID. ssh protocol v. 2.0 & 1.5.
Erlang SSH by Ericsson AB is the Erlang/OTP programming environment's SSH server & client. Supports sftp. Erlang source code & binaries under the Erlang Public Licence (derived from MPL). Probably supports ssh protocol v. 2.0 & 1.5.
Twisted.Conch is an SSH server & client written in Python and the Twisted networking framework. Supports port forwarding, telnet, vt102 terminals, sftp. Python source code (script) under the MIT/X11 licence. ssh protocol v. 2.0 only.
Paramiko is an SSH server & client written in Python. Supports port forwarding, sftp. Python source code (script) under the GNU Lesser General Public Licence. ssh protocol v. 2.0 only.
tinyssh is a minimalistic SSH server by Jan Mojžíš implementing a subset of SSHv2 features. It defaults to using its own crypto library compatible with NaCl, or can be compiled to use NaCl. C source code under the CC0 permissive licence. ssh protocol v. 2.0 only.
ftpsshd by Per-Erik Martin is a server for tunnelling ftp over SSH 1.x. Source only, under the GNU General Public Licence.
libssh2 by Daniel Stenberg and Sara Golemon is a library implementing the ssh 2.0 protocol. C source code under the BSD licence. Works with either OpenSSL or libgcrypt. ssh protocol v. 2.0.
libssh by Aris Adamantiadis is a library implementing the ssh 2.0 protocol. C source code under the GNU LGPL licence. Works with OpenSSL. ssh protocol v. 2.0.
sftp by Brian Wellington is an ftpd and ftp client that operate over any SSH tunnel, or over rsh. Should not be confused with the sftp protocol in the ssh 2.0 protocol suite, which is a newer protocol and incompatible. Source & binaries under the GNU General Public Licence.
Virtual Private Server (aka SecureVPS) by David Sifry is a Linux-based VPN implemented by running PPP across an SSH tunnel. Source & binaries under the GNU General Public Licence. ssh protocol v. 1.5.
gwpop is Stéphane Bortzmeyer's script to tunnel existing POP software over SSH, without modification.
ScanSSH by Niels Provos is a network-based protocol scanner to identify the versions of SSH servers in use. Requires libpcap, http://www.tcpdump.org/ . Source only under the BSD licence.
LADON Project by Stefan Mangard is creating administrative tools (as extensions to Portable OpenSSH) to distribute SSH host keys (both ssh protocols v. 2.0 & 1.5) using DNSSEC.
SecPanel is Steffen Leich's X11 / Tk/Tcl front-end graphical shell for ssh and scp. Source & binary under the GNU GPL.
KSSH is Andrea Rizzi and Kevin Lo's X11/Qt front-end graphical shell for SSH. Source code under the GNU General Public Licence.
SSH Buddy by Charles Wright is an X11 / Expect / tk/tcl widget to manage multiple SSH login settings. Source code (script), licence unstated (proprietary by default).
[Gone from http://sundilla.net/sshbuddy/]
Scponly by Joe Boyle (email@example.com) is a shell giving a login account remote access to scp but no other form of access. Source code under the BSD licence.
Net-SSH-Perl is Benjamin Trott's CPAN Perl module for ssh/scp client access. Source code (script) under a free-usage licence. ssh protocols v. 2.0 & 1.5.
kio_fish is Ernst Ferstl's middleware for KDE2/3 to view and manipulate remote files in Konqueror using URI "fish://user@remotehost". Included standard in KDE3.1's kdebase package. KDE 2.2 and 3.0 packages may not furnish it. Source code under the GNU GPL.
KDESSH is Geert Jansen's X11/Qt front-end graphical shell for SSH. Merged into the kdeutils. Source code under the Artistic Licence.
ssh-gui is Mark M. Tobenkin's X11 graphical shell for SSH. Source code under the GNU GPL.
autossh is Carson Harding's utility to start ssh and monitor it, restarting it if it dies or hangs. C source code under BSD licence.
RSTunnel is Amram Bentolila's VPN over SSH transport. Bourne shell script under the GNU GPL.
SSH ManaGeR is Kevin C. Krinke's SSH wrapper script to manage multiple hosts, logins, and ports. Perl script under the GNU GPL.
Tosca is Gianugo Rabellino's graphical key-management tool for SSH. Java source code under the BSD licence. Binaries are Win32 or OS X Cocoa or X11.
Keychain is Daniel Robbins's front-end utility for ssh-agent to manage your passphrase. Bourne shell script under the GNU GPL.
Yafc (Yet Another FTP Client) is Martin Hedenfalk's console-mode ftp client that also supports the SSH2.x sftp protocol. C source code under the GNU GPL. ssh protocol v. 2.0.
rssh is Derek Martin's restricted shell for scp, sftp, cvs, rsync, and rdist, giving remote users file-transfer access only. C source code under the GNU GPL. ssh protocol v. 2.0 & 1.5.
Red Bird SFX by Kandmtech, LLC is a graphical shell for sftp and scp file transfers (copy or move). Also supports crypto key generation and remote manipulation of owner/group/rights metadata, ability to type in filenames to fetch non-browseable files, per-site stored preferences/credentials. Proprietary, binary-only. ssh protocol v. 2.0 & 1.5
Chrootssh is OpenSSH with a patch to chroot users to specified subdirectories. C source code and binaries under the BSD licence. ssh protocol v. 2.0 & 1.5
Fugu is Wesley Craig's Mac OS X / Cocoa graphical front-end for sftp, scp, and ssh. Requires OpenSSH, which OS X's BSD subsystem furnishes. C source code under the BSD licence.
dataComet-Secure Advantage by VX Databeast, Inc. is a Mac OS X / Cocoa telnet, 3270, and SSH client. Binary-only proprietary code. ssh protocol v. 1.5.
JellyfiSSH (formerly SSHelper) by Marcus Radich is a Mac OS X / Cocoa graphical front-end for managing and launching SSH sessions. Requires OpenSSH, which OS X's BSD subsystem furnishes. Binary-only, proprietary code.
SFTPPlus by Pro:Atria Ltd. is an SSH1/SSH2 server & client for Win32 and sundry Unix platforms. Also does FTP, HTTP, FTPS (FTP over SSL) and HTTPS file transfer. Proprietary, binary-only. ssh protocol v. 1.5.
VShell by Van Dyke Technologies, Inc. is an SSH server. Supports ssh, scp, sftp, port forwarding/tunneling. User ACLs for fine permissions control, supports chrooting, configurable "trigger" actions. Optional Kerberos v5 auth. Proprietary, binary-only. ssh protocol v. 2.0.
PuTTY by Simon Tatham is an SSH & telnet client. Source & binaries under a free-usage (MIT) licence. pscp, Tatham's separate command-line executable for scp, is at the same site. port-forwarding is supported, as is psftp, Tatham's separate command-line client for the SSH2-family sftp protocol. ssh protocol v. 2.0 & 1.5.
Mocana Embedded SSH Server by Mocana Corp. is a small, fast ssh server primarly for embedded use. Also does telnet-ssl, tunneling, port forwarding. Extensible. Proprietary software, binary and source available. ssh protocol v. 2.0
Mocana Embedded SSH Client by Mocana Corp. is a small, fast ssh client primarly for embedded use. Also does telnet-ssl, tunneling, port forwarding. Extensible. Proprietary, software, binary and source available. ssh protocol v. 2.0
Iconfident SSH by Icon Labs is a small, fast SSH server and client primarily for embedded use. Proprietary software available in source and binary forms. ssh protocol v. 2.0 & 1.5.
GPuTTY is Pierre Ponchery's graphical SSH front end for X11/ GTK+, emulating PuTTY. Source code under the GNU GPL.
Cyberduck is David V. Kocher and Yves Langisch's graphical client software for MacOS X for FTP and SFTP, WebDAV, and cloud storage (OpenStack Swift, Amazon S3, Backblaze B2 and Microsoft Azure). It interacts with the MacOS X Finder graphical shell for drag and drop, and with Growl for notifications, and can open some files in external file editors. Source code in Java and C# under the GNU LGPL licence, using the MacOS X Cocoa UI framework. ssh protocol v. 2.0.
Transmit is Panic, Inc.'s graphical file transfer program for MacOS X, supporting FTP, SFTP, S3, WebDAV, Google Drive, Dropbox, and other cloud services. Proprietary software available in binary form. ssh protocol v. 2.0.