What is a Firewall?

Written by Christoan Smit

16 Aug, 2019

In the world of IT, not having a firewall is a bit like a house with a missing front door – not exactly secure.

In plain English, a firewall could be either a device or a software program that scans the Internet and internal network traffic for intruders, and if it’s a really fancy firewall like the ones we use at our Venom IT data centres, it can scan for malware too, along with a plenitude of other features.

Here is a list of things a high-end firewall device can do:

· A growing cause for concern among employers is the profusion of apps found on the internet and in app stores, and for two reasons: Firstly, they can be huge time wasters, distracting employees when they should really be working, and secondly, if not more importantly, many of these apps pose huge security risks. This is where App Control comes in – a high-end firewall will block all apps on a list that you give it, or conversely (and more securely) allow only the apps that are on a predefined ‘whitelist’.

· Another cause for concern among employees is the inordinate amount of time spent by their employees on websites that are not work related. Web filtering is yet another feature provided by a top-notch firewall, and it could well boost the productivity of your office if implemented properly. Linked to this is Web usage monitoring, which will give you a scheduled report on e.g. what websites each employee visited and how much time they spent on it.

· A good firewall can also prevent Denial of Service attacks. DoS attacks are when hackers try to disable your system by some manual override or backdoor in your system, and prevent you from being able to use your computers. DDoS attacks are when hackers try to swamp your system with so much traffic that it crashes and you can’t do any work and none of your clients can get through to you.

· Sandboxing is the ability of the firewall to open a suspicious program in a ‘sealed’ environment to check what it actually does. If there’s nothing wrong with it, the firewall will pass it through, or if it was malicious, the firewall will kill the programme and send a warning to the system administrator. Our own firewalls take this a step further – they talk to each other and automatically update each other’s ‘knowledge base’ of malicious programs.

· Content disarming & reconstruction is when a perfectly innocent email attachment somehow got infected with malware – usually on the sender’s side. A next-generation firewall like the ones used by Venom IT will ‘strip out’ the malicious code and attempt to restore the attachment to its original, uninfected state.

· High-end firewalls come with built-in Antivirus features. This is called Unified Threat Management, or UTM for short, and comes with real-time updates as well as sending new threats to the developers in the Security Research team. Caveat: Even though the firewall has a built-in antivirus, you should still have an antivirus installed on each machine you use.

· A really high-end firewall will also scan your network hardware for vulnerabilities – it mimics automated tools used by hackers to try and break in, and then reports when it finds a weakness.

· Remember how hackers use DDoS attacks to try and flood your system with traffic to prevent you from being able to work? Their favourite tool for this is something called a botnet – a network (of sometimes millions!) of other people’s computers that had all been compromised and come under the control of the hacker. A next-gen firewall has a list of Internet domains & addresses of known Botnets, and will automatically block them, never even giving them a chance to get through to your network. It can use the same IP address blacklisting/whitelisting for other sites too – you could for instance block entire countries or only allow computers located in certain countries or areas to access your network.

· Lastly, a top-end firewall can act as a kind of ‘middleman’ between your office and any external, web-based services (e.g. email, office solutions, practice management software etc) that you use on a regular basis. The acronym for this is CASB – Cloud Access Security Broker, and it will try to enforce your own security protocols externally, wherever it can.

Investing in a good firewall is absolutely worth the cost. To put it in another way: How much will it cost your business to not have a decent firewall?

Cloud services put high-end, expensive services within anyone’s reach.

The good news is that you don’t have to spend thousands of Pounds on top-end firewalls – you can piggy-back off someone else’s. If, for instance, you have a Hosted Desktop from Venom IT, all your data will be kept behind a military-grade firewall array and on encrypted drives. That is the magic of Cloud computing – you can have top-end services that otherwise would’ve cost you a fortune. Get in touch today and find out how cloud services can boost your productivity, increase your security and cost you less in the long run.