Caching proxies remember web pages and serve them up locally, saving both money and time. The most intelligent members of this family also remove dangerous content and provide transparent bridging.

We’ll show you how to build your own Netfilter extension with this example of a musical firewall.

The Apache ModSecurity module provides extra protection for your web server. We'll show you why this optional application firewall is quickly becoming a favorite of webmasters and security experts.

SELinux provides a comprehensive Mandatory Access Control system for Linux, if you are ready for all the details.

Security Enhanced Linux or App Armor? Linux Magazine invited two well-known personalities from Red Hat and Novell to debate the merits of their security systems.

Your Linux system may not be so airtight after all. To understand the threats, you need to think like an intruder. We'll show you what the intruders are thinking now about the Linux 2.6 kernel.

When an attacker succeeds in infecting a victim’s system, the attacker inherits the victim’s privileges. App Armor beats the attack by reducing the potential victim’s privileges to a minimum.

When ports on a host start opening and closing like window shutters in a gale, it’s time for admins to pay attention.