Router vs firewall, can you actually compare them?

24.07.2024 5,870 22

Martin Pramatarov

Routers and firewalls are two technologies that have different purposes, so why do we even compare them? Thanks to the evolution in the tech world, both routers and firewalls are constantly changing. Now you can find routers with built-in firewalls, very advanced hardware firewalls, and software firewalls. Check the ultimate router vs firewall comparison. 

What is a router? 

A typical router is a network device that manages the traffic on the network. In order to do it, it forwards data packets between different devices and networks. When the router receives the data packets, it checks them and compares them to its routing table. Then it redirects these packets to the next network on the way to the final destination. In short, it routes data between IP subnets and manages traffic between multiple devices on a local network and external networks.
You probably have one at home that lets you connect to the Internet. For that purpose, the router does network address translation (NAT). This allows multiple devices to have different IP addresses on the local network and the same public IP address to connect to the Internet. 

 Purpose 

The routers manage the traffic. They direct traffic (data packets) between different networks, based on the IP addresses of the sender and the receiver. They ensure efficient data flow and connectivity across different network segments. 

 The layer of operation 

Routers operate on Layer 3 (network) and 4 (transport) of the OSI model. As we already mentioned, routers primarily deal with IP addresses and data routing, but they can also manage some aspects of the data transport. 

 Encryption 

Typically, these devices don’t offer encryption. Efficient transfer is not always a synonym of secure transfer. Just check the UDP protocol. It does not offer any verification method to establish a secure connection. This has caused many problems with the DNS network.  

 Network sharing 

The router can share an Internet connection between various networks (LANs, WANs, etc.), enabling multiple devices to “talk” to each other and connect to the Internet simultaneously. 

 What is a firewall? 

The firewall is a hardware or software barrier. It filters the data passing through it and that way it protects the devices from spam and malicious software. The firewall applies rules to the traffic, and based on the rules discards or allows the traffic to pass. It is the sentinel that keeps your devices safe and allows communication on selected channels only. 

 Types of firewalls: 

• Hardware firewalls: The firewall can exist as a stand-alone device or it can be built-in in a router. It is very convenient to have it built-in. That way you will need one less device and you will have active protection on your network. The firewall does its job by reviewing the headers of the data packets and then it makes a decision whether to trust them or drop them. 

• Software firewalls: The software firewall is an application that can be part of your antivirus suit or it can come separately as a standalone program. It can be installed on a server, and protect the rest of the devices. You can also install it on your device, start it, or stop it as you please. It won’t protect the whole network, just the device on which it is installed. To protect all the devices on the network with a software firewall, you would need to install it on each of them. A drawback is that the software runs in the background and it could slow down your device. 

 Purpose 

The firewall’s purpose is to filter data and that way to protect the network. It can control the incoming and the outgoing traffic, based on the rules, the network administrator has defined. Such rules can be banned ports of communication, data packet limits, session duration, maximum number of concurrent devices connected, and more.
The firewall can stop unauthorized access and different cyber threats such as malware. 

 The layer of operation 

The firewall operates on Layer 4 (Transport Layer), and Layer 7 (Application Layer) of the OSI model. It depends on the type. This allows firewalls to inspect not only the data transport mechanisms but also the content and applications, that are part of the communication. 

 Encryption 

The firwall can encrypt the data before transmission. This adds a layer of security while the data is transferred. If you want to know a bit more about encryption, check out our article about TLS certificates and how you can use them to encrypt data. 

 Network sharing 

No. The firewalls are simply not designed for network sharing. They serve to protect the network, and they do a wonderful job. 

 Router vs firewall, a comparison table 

 Real-World examples 

Let’s think about a small office setup. You can use a single router with a built-in firewall to route the traffic and provide basic security. Yes, this solution won’t offer top-notch security, but it will be a cost-effective solution that you can easily implement.
If we are talking about a big enterprise environment, then you will need multiple routers and dedicated firewall devices. This combination will provide enhanced performance and security. 

 What do experts recommend about routers and firewalls? 

Network experts, usually recommend a so-called layered security approach. They recommend business owners choose separate, dedicated devices. This way, the performance and security will be better. 

 Router vs firewall, the conclusion 

So should you go for a router that has a built-in firewall? If you have a small deployment – yes. It is not a bad choice. However, in case you have a larger deployment you can use a dedicated router and a dedicated hardware firewall. You can benefit from advanced features like better VPN capabilities, higher traffic speed, and easier configurations.
As technology continues to advance, the distinction between routers and firewalls may blur even further. However understanding their core functionalities and how they complement each other remains crucial for designing and maintaining secure, efficient networks.