What Is a Hybrid Firewall?
Hybrid firewalls consist of multiple firewalls, each providing a specified set of functions. For instance, you can use one firewall to execute packet filtering while another firewall acts as a proxy. In this way, you can tweak the performance of your security system, taking advantage of the diverse range of capabilities the different firewalls offer.
How does a hybrid firewall work? As a hybrid firewall example, you can set up two firewalls that work in tandem, one of which is your proxy firewall and the other filters data packets. The firewall acting as your proxy server processes web requests while the packet filtering firewall ensures that all data coming into and exiting your network security system is safe. In this way, the two firewalls act as a single hybrid system, protecting your organization in two different ways.
Another benefit of a hybrid firewall architecture is you can add a new firewall to an existing security system without having to remove or replace your current firewall. This hybrid firewall application enables you to add another layer of security without compromising the benefits of your existing architecture. The ability to add firewall infrastructure to an existing system can allow you to set up a distributed firewall, which enables you to establish security rules that control access between two separate networks.
Hybrid Firewall vs. Traditional Firewall
Selecting your next-generation firewall (NGFW) solution will depend on whether the benefits of a hybrid firewall system provide adequate payoff for your organization. Suppose you already have a stateful firewall, which works by analyzing a safe state and then ensuring anything that violates the parameters of the state gets rejected. You may be relatively satisfied with the performance of your current network firewall, but you still want to add a layer of security.
If you opt for a hybrid firewall architecture, you can keep your stateful packet inspection firewall and use an additional unit to fine-tune the kind of traffic you allow in and out of your network. In this situation, there is no need to expend extra time ensuring your new firewall performs the duties of your stateful one. This can save time and resources while also giving you peace of mind around your protections.
On the other hand, with a traditional firewall architecture, you typically replace the stateful firewall altogether and program your replacement firewall with what it needs to protect your network adequately. In many situations, this is fine, particularly because the new firewall can easily do everything the stateful one can. A traditional firewall architecture involves, in a way, putting all your eggs in one basket. The reason it can still be effective is that new firewalls usually provide all the protections of older ones and significantly more.
Advantages of a Hybrid Firewall
Some of the general benefits of a firewall also apply to a hybrid setup, especially because you are using multiple firewalls. If configured properly, you are not sacrificing any of the protections of a typical firewall architecture. The advantages include:
- Flexibility when it comes to incorporating two or more firewalls in your system. There is no need to identify a firewall that does everything you need. You can simply choose one that does not do what your existing firewall does, then combine the two.
- Granular control of the protection of your network. With a hybrid firewall arrangement, you can take full advantage of certain features, analyze the effect they have on the safety of your system, and then limit one firewall to covering those protections. You can then leave the rest of your protection up to the other firewall. If certain types of threats are getting through, you can more easily identify which firewall’s settings need to be adjusted.
- Easier threat isolation. With two firewalls, you can assign one to a specific type of threat and the other to cover the rest of the threats on the landscape. For example, one firewall can be designated as the data exfiltration firewall, dedicated wholly to threats that involve the theft of data. All of its alerts—if there are any—will pertain to data theft. This can help the IT team hone in on particularly concerning threats.
Disadvantages of a Hybrid Firewall
A hybrid firewall may unnecessarily complicate your network without providing much tangible benefit. One of the primary disadvantages of a hybrid firewall architecture is the security challenges it can present. If one of your firewalls is not properly configured, threats can easily sneak through. In other words, firewall configuration can—and should—take twice as long with a hybrid firewall setup. Some organizations have neither the extra time nor people power to deal with multiple firewall setups. A relatively simple configuration error can result in a costly breach.
In addition, administrators have to fight the tendency to overly trust older firewalls, particularly because they can let some newer threats sneak by. To illustrate, with a FortiGate NGFW, you get machine learning capabilities that can detect threats without even using header information. An older firewall may not be able to do that, and trusting it to protect your network can be a mistake.