The content of this article can be associated or mapped to CompTIA Security+ Exam Objective 1.0 “Network Security” or more specifically, firewalls and web filters. First off the title requires a brief explanation. No I am not a fascist but one of my professors called me a security Nazi after grading one of my assignments discussing firewall rules and policy development for a fake company. That being said, I am frequently asked by my clients what they can do to better harden their enterprise. They ask about the latest technology or the latest threat like ‘Ransomware’. To be perfectly honest many organizations are already equipped to handle such threats. All it takes is a little bit more support from management to enforce said policies. But let’s talk about the tech for a minute.
Web Filters are by far my favorite piece of IT Security Infrastructure. If we can all agree that the internet is a boiling cesspool of viruses, identity thieves, and quizzes that tell you which care bear you are and the internal network or LAN is our bastion of good – achieving the company mission statement. Then the web filter is one of the best things to protect the LAN from the evil that lurks in the World Wide Web. I feel the eyebrows rising but bear with me and remember I’m about to talk about firewalls too. If you are a Network Security Administrator then the web filter is your best friend. For those that don’t know, the web filter is a program that screens websites for permitted or blocked content and permits or blocks said content respectively. (Rouse, 2017)
So why do I favor the web filter you ask? Because it protects us from the most lethal threat to a corporate network…The USER! (DeCarlo, 2007) If we examine some of the biggest daily issues that a network faces many of the issues can be tied to user activity within the network. Whether it’s Johnny in the HR department checking the local scores of his favorite team or Suzie in accounting checking her horoscope, each site they visit poses the potential threat of delivering malware to their machine. So the best thing a network admin can do is block sites like that altogether and prevent users from visiting those sites. My professional recommendation is to block any and all URLs that are not specifically required for the network to function. It’s harsh but let’s face it Johnny and Suzie need to be working and not using company assets to do the useless stuff the internet has to offer. This is best done through a whitelist feature that is equipped in nearly all modern web filters. Whitelisting is great because it implicitly denies communication with all URLs that are not listed. Johnny and Suzie will be okay if they want to waste company time, they can do it with their personal smartphones on the public Wi-Fi so that excuse about morale is a poor one at best.
Firewalls are my next favorite security implement because they provide that barrier from the evils of the internet that the web filter doesn’t cover which originates from the internet. Where it can be argued web filters basically protect the LAN from outbound traffic, the firewall protects it from inbound traffic. You know; all those threat agents from China, Russia, and everywhere else on the planet that is fighting to get in and steal your customer or patient data. Firewalls are a necessity. It is important to discern that firewalls do perform some of the same tasks a web filter does so while a network could survive on just a firewall just remember that security is about layering and redundancy. That is why many firewalls come equipped with a web filter application to work in concert with the firewall. I know I mentioned corporate networks a lot but the good news is these features are also often contained within aftermarket wireless routers. My Asus has both a firewall and a web filter, in the form of parental controls I can leverage to protect my home network as well. Which, if you have small children or teenagers, you should appreciate and employ because let’s be honest the last thing on a kid’s mind is security while surfing the web.
DeCarlo, A. L. (2007, March 21). Biggest security threat? Your users. Retrieved February 16, 2017, from http://www.computerworld.com/article/2543940/networking/biggest-security-threat–your-users.html
Rouse, M. (n.d.). What is Web filter? – Definition from WhatIs.com. Retrieved February 16, 2017, from http://searchsecurity.techtarget.com/definition/Web-filter