How to stay one step ahead of hackers.

By Alan Rimm-kaufman

Many operating systems turn on unneeded services by default. For example, unless explicitly told otherwise, a newly installed server may leave port 23 open for telnet, and port 21 open for FTP.

Every open port and service exposes you to more risk. Turn off everything that isn’t needed.

Free tools are available to help you determine which ports are open on your machine. (Indeed, hackers use similar tools to probe your network.) Free tools include: Nessus (http://www.nessus.org), Nmap (http://www.insecure.org), and Security Auditor’s Research Assistant (http://www-arc.com/sara).