SSH for Mac OS Classic (9.x and prior)

• NiftyTelnet SSH by Jonas Walldén. SSH & telnet client. Binary-only proprietary code under a free-usage licence. Includes scp. Omits support for the (insecure) Arcfour cipher. Does not do port forwarding. ssh protocol v. 1.5.
  http://www.lysator.liu.se/~jonasw/freeware/niftyssh/
  ftp://ftp.zedz.net/pub/crypto/programs/ssh/nifty_telnet/

• F-Secure SSH. F-Secure Corporation's (formerly Data Fellows, Ltd.) proprietary, binary-only client. Does not do scp. Does port forwarding. ssh protocol v. 2.0 or 1.5 (separate products).
  http://www.europe.datafellows.com/products/cryptography/f-sshtt.htm

• AppGate by AppGate (Martin Forssen). Proprietary client. Optional Java-based front-end GUI. Authentication methods include ACE/SecurID, Entrust, iD2, and Telia EID. ssh protocol v. 2.0 & 1.5.
  http://www.appgate.com/products/appgate_client.html

• BetterTelnet. Sassy Software's (Rolf Braun's) client, a descendant of NCSA Telnet. Braun has an SSH-client beta module, which will be publicly released soon(?), given the RSA patent being no longer an obstacle, and is being delayed only by negotiations with USA Commerce Department "export" regulators. Source & binaries. GNU General Public Licence. ssh protocol v. 1.5.
  http://www.cstone.net/~rbraun/mac/telnet/

• MacSSH, Jean-Pierre Stierlin's SSH & telnet client based on Rolf Braun's BetterTelnet, Matthias Neeracher's GUSI, and Niels Möller's LSH. Project is complete and functional but no longer maintained. Source and binaries under the GNU General Public Licence. ssh protocol v. 2.0 only.
  http://www.macssh.com/
  http://pro.wanadoo.fr/chombier/MacSSH/SSH_info.html

• MacSFTP is Jean-Pierre Stierlin's sftp client based on Portable OpenSSH and Matthias Neeracher's GUSI. Source and binaries under the GNU General Public Licence. ssh protocol v. 2.0 only.
  http://www.macssh.com/
  http://pro.wanadoo.fr/chombier/MacSFTP/SFTP_info.html

• dataComet-Secure Advantage VX by DataBeast, Inc. is a telnet, 3270, and SSH client. Binary-only proprietary code. ssh protocol v. 1.5.
  http://www.databeast.com/

In 1997, Bernt Budde <Bernt.Budde@cycore.com> created a functional MacOS port of Ylönen's SSH, but has not retained a copy.