Firewalls: Why every business with a network needs a firewall
With cyber attacks on the rise and the rapid rise of artificial intelligence (AI) accelerating the pace of change, compounding the threats and lowering the barrier to entry, the cyber world is a more dangerous place than ever before.
And whilst the age of AI and global connectivity brings about massive business opportunities, it also means that it is more important than ever to protect your business assets and data from these attacks which is why every business with a network needs a robust firewall, coupled with a comprehensive IT strategy.
But what exactly is a firewall and how does it protect a network? In this blog, we’ll take a look at these important questions and also consider what a firewall doesn’t do.
What is a firewall?
A firewall is a network security system that can either be hardware or software that protects the trusted network from unauthorised access from external networks and external threats. It inspects all the data passing in or out of your network, ensuring that the traffic is legitimate, and protecting your business systems from any malicious users or programs.
It therefore serves as a protective boundary between the trusted devices on your network and untrusted systems, for example on the open internet.
Because firewalls can filter out malicious traffic, they can effectively protect you from a number of online threats. Depending on the firewall system and the needs of the network it’s protecting, firewalls can play a part in defending a network against hacking attempts, malware, malicious links, DDoS attacks, and more. Next-Generation Firewalls (NGFWs) have a number of added features giving further protective capabilities compared to “old-school” firewalls.
What’s a Next-Generation firewall?
Next-Generation Firewalls, like the Cisco Meraki MX range, marry traditional firewalling capabilities with a host of “Unified Threat Management” (UTM) technologies. These capabilities include application-based firewalling, content filtering, web search filtering, SNORT®-based intrusion detection and prevention, Cisco Advanced Malware Protection (AMP), site-to-site Auto VPN, client VPN, WAN and cellular failover, dynamic path selection, web application health, VoIP health, and more.
How do firewalls work?
Firewalls are usually installed at points where your internal, trusted network meets external, untrusted networks like the open internet. This allows the firewall to inspect traffic as it enters and leaves your network.
If the traffic is trying to do something that contravenes your internal security policies or something that the firewall otherwise detects as potentially malicious, then that traffic will be stopped in its tracks. Many firewalls work with online threat libraries to guard against known threats that have already been detected elsewhere.
When your organisation uses a firewall, you will generally be able to create custom rules that help govern your network. You could, for example, block access to unprofessional or distracting websites; bar data from travelling over certain ports; limit certain kinds of traffic; or set alerts to flag when certain criteria are met.
Do firewalls defend against all cyber-attacks?
Unfortunately not. Simply having a firewall won’t render you immediately immune from cyber incidents. Currently, no single cyber or network security solution will ever leave you 100% secure.
Though a perimeter firewall is well placed to filter out many types of inbound threats, there are still ways that bad actors can gain a foothold within your network. Lack of awareness of how to spot social engineering is still a big issue, and can be used to hoodwink unsuspecting network users into giving hackers access to sensitive resources which is why staff cyber security awareness training is vital. Also, incorrectly securing internet of things and ICS devices can present significant security risks.
Instead, you should create a comprehensive layered combination of security tools that address your individual risk factors and technical needs.
Benefits of firewalls
A firewall is your first line of defence against hackers and other unauthorised external users
A firewall acts as a barrier, or shield, between your internal business network and the rest of the Internet. Without a firewall, it is possible for external users to access your private business assets. While many organisations use Network Address Translation (NAT) to bridge Internet and external IP addresses, NAT will not block incoming traffic. Only a firewall can do that. Without a firewall, your organisation’s assets and data are at risk.
Next-Gen firewalls also help to control what leaves your network
You may be surprised to see that NGFWs can also stop potentially damaging outbound traffic too. Many next-gen firewalls feature some kind of data loss prevention functionality which monitors outgoing traffic to make sure that sensitive data isn’t being shared in insecure or unauthorised ways. This can be used to protect sensitive login details, payment information, or even industry secrets from leaving your network infrastructure.
Firewalls can protect both internal and remote teams
Having team members work remotely can be essential. However, not all external networks are going to have the same strict levels of security as your internal network.
Yet most firewalls nowadays, such as the Cisco Meraki MX range, can protect remote workers with remote VPN functionality. Effectively, this allows authorised parties who are outside of your network to “dial in” to your firewall through the internet and benefit from the same security rules and policies as they would if they were working at your premises. This enhances productivity, collaboration, and data sharing.
A firewall lets you block access to unapproved websites
In addition to stopping unauthorised external users from accessing your network, a firewall can stop your users from accessing specific external websites. For instance, you could set up a policy that blocks access to unprofessional content and social media sites like Instagram and X from your network.
A firewall can protect your business from malicious code
Some strong firewalls will inspect the traffic going into and out of your network. They look for and block viruses, worms, spam, and other unwanted Internet traffic. They will also log intrusion attempts as well as other violations of business policies. This enables you to examine unauthorised access attempts and other suspicious activity.
Many of these strong firewalls will also let you maintain a list of known malicious applications and known good applications. They will block the malicious applications while enabling the good ones.
Firewall logs give insight into how your network is being used
A firewall isn’t just a box that sits at the gateway to your network and does its thing. Authorised parties can access a wealth of logged information held within.
The types and formats of data that your firewall saves will vary depending on your firewall’s model and set up. But generally, you can:
- See whether any of your users are flouting IT policies
- Identify devices that are accessing unproductive content
- Identify repeated access (read: hacking) attempts from specific, external IP addresses
- Uncover suspicious connection requests and scans
- Monitor regular network activity to monitor and continually improve your security policies
- and much more
Set off the network security alarm with alerts
As well as simple logging, many firewalls also allow you to set up alerts that notify your IT teams as soon as a potential major incident is on the horizon. Again, the nature of alerting will depend on the solution you choose, but many NGFWs can alert you for example when:
- A threat has been detected
- When a security rule violation is detected
- An attempted port scan is detected (which could be a criminal carrying out pre-attack cyber recon)
- A large amount of data is trying to enter from or leave for a single, unknown IP address
- Sensitive data is attempting to leave the network
- The firewall’s internal resources are reaching their limit
- An update to the firewall needs to be installed
Firewalls should be part of a broader cyber security strategy for your business
Firewall protection is only one element of a good business cyber security strategy. If you don’t have internal expertise, a company offering IT support for business can help you develop and implement an effective cybersecurity strategy and firewall system to protect your business.
Xcomm can develop a cyber security strategy customised to suit the specific needs of your business as part of our outsourced IT support services.
About Xcomm
Xcomm offers a broad range of secure remote access solutions, market-leading data protection products and related professional data security services – all designed to help you safeguard business processes and stay compliant with regulations and best practice. Xcomm is a Cisco Meraki partner and specialises in Next Generation network security products and services.
From IPSec VPNs, firewalling and data encryption to multi-factor authentication, email security, spam, spyware, Trojan and virus protection, Xcomm has the solution.
Optimise your business communications cybersecurity in 2024 by contacting the Xcomm sales team.
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