What is a Cloud Firewall? Why It's Essential for Small Businesses

Tom Grange
By Tom Grange, Director - Connectivity Business

If you use the cloud and it’s essential to running your business, then cybersecurity should be on your radar.  Especially as small businesses, in particular, are prime targets for cybercriminals!

And unlike big corporations, small businesses don’t often have the infrastructure to keep out unwanted infiltrators in all business areas. 

But when it comes to the cloud - this is where firewalls come into play.

In this guide, we’ll walk you through everything you need to know about cloud firewalls and their benefits to your business. 

Animation with orange security shield in a box surrounded by colourful dots

What is a cloud firewall?

Cloud firewalls are virtual, software-based security products built to stop and filter out potentially malicious network traffic. Also known as Firewall-as-a-Service (FWaaS), and unlike traditional firewalls, cloud firewalls are hosted in the cloud

As a new technology, they’re designed for modern business needs. 

How does a cloud firewall work?

Traditional firewalls filter traffic entering on-premises networks and individual devices. A cloud-based firewall, however, protects software-as-a-service (SaaS) applications by filtering incoming and outgoing traffic using virtual appliances in the cloud. 

When users connect to cloud resources, the firewall meticulously screens their identities and closely monitors data flow across the network. Whether members of your business are working from the office, remotely, or on the go, a firewall ensures that their access remains protected and authenticated no matter what.

Behind the scenes, dedicated IT teams are equipped with the tools and insights needed to continuously track user activities and analyse any network traffic patterns that look out of the ordinary. This proactive approach allows businesses to identify any anomalies or potential threats as soon as they arise.

How many types of cloud firewalls are there?

In the realm of safeguarding your digital assets in the cloud, there are several different cloud firewalls available for your business — and it’s important to choose the right one for you.

  • Network-based firewalls — These firewalls are the gatekeepers of cloud infrastructure. They scrutinise network traffic based on things like IP addresses, port numbers and protocols. A network-based firewall won't grant access if someone doesn’t have the right credentials.
  • Web-application firewalls (WAF) — In the world of web applications, WAFs reign supreme as cybersecurity experts. Their role is to safeguard your applications from an endless barrage of online threats. They continuously inspect inbound and outbound data streams to intercept and neutralise dangers, such as SQL injections and cross-site scripting attacks.
  • Next-generation firewalls (NGFW) — These firewalls aim to protect an organisation's own services in a platform-as-a-service (Paas) or infrastructure-as-a-service (IaaS) model. Armed with skills such as deep packet inspection and intrusion detection, NGFWs excel in spotting even the most covert threats — they always aim to be one step ahead.

What is the purpose of a cloud firewall? 

A cloud firewall serves a vital role in securing your business's digital assets and infrastructure. Some of their key functions include:

  • Security enforcement — A cloud firewall is responsible for enforcing security policies and rules within your business's digital landscape. It carefully inspects all incoming and outgoing network traffic and makes decisions on predefined criteria that you’ve already laid out. It allows for authorised traffic whilst blocking or flagging any potentially malicious activity.
  • Access control — Cloud firewalls manage who gets the green light to access your business's digital information. And, by applying these rules, it assures that only authorised users and applications are granted entry. 
  • Traffic filtering — It acts as a traffic filter, continuously analysing data packets to identify and block potential threats, such as malware, viruses, or suspicious activities. This proactive filtering helps protect your cloud environment from potential security breaches.
  • Segmentation — In cloud architectures, such as those seen in platforms like AWS or Azure, cloud firewalls play a key role in how the network is structured. They serve as digital architects, creating distinct zones or segments within your cloud. By managing communication between different components, they enhance security by limiting the lateral movement of potential threats. 
  • Threat detection and prevention — Many cloud firewalls have advanced threat detection mechanisms, such as intrusion detection and prevention systems (IDPS). These systems continuously monitor network traffic patterns and promptly identify any suspicious behaviour. They immediately block or mitigate potential threats, contributing to your business's cloud security.

What are the benefits of using a cloud firewall? 

There are many benefits of using cloud firewalls for your business, but there are some that are a bit more compelling than others.

Scalability expansion

Unlike traditional firewalls that may require significant hardware upgrades, cloud firewalls can easily adapt to the changing needs of your digital environment. Whether you're expanding your operations or experiencing fluctuations in traffic, a cloud firewall can seamlessly adjust its capabilities to accommodate these changes, ensuring your security scales with your requirements.

Offers advanced reporting options

Cloud firewalls offer advanced reporting capabilities that provide valuable insights into your network's security and traffic patterns. 

These reports help you gain a deeper understanding of your digital landscape, enabling you to make informed decisions to enhance your security posture. You can identify potential threats, track user activities, and pinpoint areas for improvement, all of which contribute to a more robust security strategy.


When compared to traditional on-premises firewalls, cloud firewalls often prove to be more cost-effective. They eliminate the need for extensive hardware investments and maintenance, reducing upfront capital expenses. Their scalability also ensures that you pay only for the resources you use, making them a great choice for businesses of all sizes — small and large!

What are the disadvantages of using a cloud firewall? 

As with most things that have benefits, there are always going to be disadvantages. For cloud firewalls, some of these include:

Managing firewall rules and policies

One challenge of employing a cloud firewall is the management of firewall rules and policies.

As your digital environment grows, so do the rules governing access and security. Keeping these rules up-to-date and aligned with your evolving needs can be a complex and time-consuming task, requiring diligent oversight to avoid misconfigurations or gaps in security.

They can be quite complex

Implementing and managing cloud firewalls can be complex, especially for businesses that have diverse IT infrastructures and numerous applications. Ensuring that the firewall rules are correctly configured and that they align with your security policies can be a daunting task. Complexity can sometimes lead to misconfigurations, which could potentially create security vulnerabilities within your business — which is something you don’t want to expose yourself to. 

Ensuring your data is secure

While cloud firewalls are essential for protecting your digital assets, ensuring the security and privacy of your data is a shared responsibility. Organisations must implement robust data encryption and access controls in conjunction with the firewall to safeguard sensitive information effectively. This collaborative effort can sometimes lead to complexities in data security strategies.

Find out more about cloud data protection with our guide. 

Get your business set with Bionic

Cloud firewalls can be a great asset to your business, helping it stay protected when it needs it the most. 

Get in touch with our team here at Bionic, who can help you get the best deals on your business connectivity, from broadband to phone and VoIP services.