Designing and Using DMZ Networks to Protect Internet Servers
Naturally, you want to carefully restrict traffic from the outside world to the DMZ. But it's equally important to carefully restrict traffic from the DMZ to your internal network (to protect it in the event that a DMZ host is compromised) and from the DMZ to the outside world (to prevent a compromised DMZ host from being used to attack other networks).
It goes without saying that you'll probably want to block all traffic from the Internet to internal hosts. (You may or may not feel a need to restrict traffic from the internal network to the DMZ, depending on what type of access internal users really need to DMZ hosts and how much you trust internal users.) In any event, your firewall-security policy will be much more effective if your firewall can distinguish between legitimate and phony source-IP addresses. Otherwise, it might be possible for an external user to slip packets through the firewall by forging internal source IPs.
By default, most firewalls don't have this functionality enabled (the feature is usually called something like anti-IP-spoofing. Even if your firewall supports it, you'll probably have to configure and start it yourself. It's well worth the effort, though.
|The True Internet of Things||Sep 02, 2015|
|September 2015 Issue of Linux Journal: HOW-TOs||Sep 01, 2015|
|September 2015 Video Preview||Sep 01, 2015|
|Using tshark to Watch and Inspect Network Traffic||Aug 31, 2015|
|Where's That Pesky Hidden Word?||Aug 28, 2015|
|A Project to Guarantee Better Security for Open-Source Projects||Aug 27, 2015|
- The True Internet of Things
- Using tshark to Watch and Inspect Network Traffic
- September 2015 Issue of Linux Journal: HOW-TOs
- Problems with Ubuntu's Software Center and How Canonical Plans to Fix Them
- Firefox Security Exploit Targets Linux Users and Web Developers
- Where's That Pesky Hidden Word?
- Concerning Containers' Connections: on Docker Networking
- A Project to Guarantee Better Security for Open-Source Projects
- My Network Go-Bag
- Build a “Virtual SuperComputer” with Process Virtualization