About OpenSSH

Resources

OpenBSD-only

For other OS's

Alternatives

OpenSSH is a FREE version of the SSH protocol suite of network connectivity tools that increasing numbers of people on the Internet are coming to rely on. Many users of telnet, rlogin, ftp, and other such programs might not realize that their password is transmitted across the Internet unencrypted, but it is. OpenSSH encrypts all traffic (including passwords) to effectively eliminate eavesdropping, connection hijacking, and other network-level attacks. Additionally, OpenSSH provides a myriad of secure tunneling capabilities, as well as a variety of authentication methods.

The OpenSSH suite includes the ssh program which replaces rlogin and telnet, scp which replaces rcp, and sftp which replaces ftp. Also included is sshd which is the server side of the package, and the other basic utilities like ssh-add, ssh-agent, ssh-keysign, ssh-keyscan, ssh-keygen and sftp-server. OpenSSH supports SSH protocol versions 1.3, 1.5, and 2.0.

OpenSSH is primarily developed by the OpenBSD Project, and its first inclusion into an operating system was in OpenBSD 2.6. The software is developed outside the USA, using code from roughly 10 countries, and is freely useable and re-useable by everyone under a BSD license.

Managing the distribution of OpenSSH is split into two teams. One team does strictly OpenBSD-based development, aiming to produce code that is as clean, simple, and secure as possible. We believe that simplicity without the portability "goop" allows for better code quality control and easier review. The other team then takes the clean version and makes it portable, by adding the portability "goop" so that it will run on many operating systems (these are known as the p releases, and named like "OpenSSH 3.3p1"). Please click on the provided link for your operating system.

The OpenBSD project sells an OpenSSH tshirt and poster. Sales of these items help to fund development.

Although the basic SSH functionality is easy to use, for power users we recommend the O'Reilly SSH book by Daniel Barrett and Richard Silverman as an excellent reference.