This page is dedicated to system security from a Hacker AND System Administrator's viewpoint.
As a System Administrator myself, being informed with current information is one of many tools
we need to be effective.
To help you understand security from a hacker perspective I have a link to
Hacking Sites dedicated to
challenge your skills as a System Administrator. Note: Everytime you select the "Hacking Site" link
you will be taken to a different site.
TCP/IP and Ethernet sniffers are the bane of good security. Other than encrypting your packets or using
the newer tunneling technologies, password compromise is always a possibility. A good policy
of terminals being used ONLY by authorized users is a good start to getting a hand on this. Also, avoid
using the ROOT shell as much as possible from remote terminals. If you need to do system maintenance try
to do it right at the server. User access should be compartmented, a strict policy of "need to know or
access" for users will ensure any passwords sniffed will limit the damage.
Read the Sniffer FAQ