SSH

SSH is a program that enables secure logins over an unsecure network. It encrypts the data passing both ways so that if it is intercepted it cannot be read.

SSH is client-server software; both machines must have SSH installed. SSH server software is installed on all the PSC machines.

You must install SSH client software on your local machine.

Why does the PSC require me to use SSH?

We are concerned with the increasing frequency of attacks on computers and networks and want to provide you with a secure environment in which to conduct your research.

Obtaining SSH for your local machine

SSH is available without charge for almost all versions of Unix. Clients for Mac and PC Windows are available free from vendors or from the Internet.

Authenticating to PSC with SSH

You can use either password authentication or public-private key authentication to connect to PSC with SSH. To use key pairs, you must use PSC's web-based key management system. Instructions for the key management system are available here.

More SSH information

These websites are good sources of information on SSH.

• A good introduction: kimmo.suominen.com/docs/ssh
• A comprehensive FAQ: www.onsight.com/faq/ssh/ssh-faq.html

For help using SSH at the PSC, contact PSC User Services.

SSH key pairs and AFS tokens: If you connect to a PSC machine which uses AFS using a public-private key pair, you will have an AFS token on login ONLY IF you are connecting from another AFS machine. If you connect to PSC from a non-AFS system, you do not receive an AFS token automatically. Use the klog command to get a token.

For more information on AFS tokens, see the AFS documentation.