What Is a Router and How Does It Work?

You might have heard of routers when talking about internet connections and Wi-Fi. These devices are used in residential and enterprise scenarios alike. But what exactly is a router? More importantly, how do these routers work? What purpose do they serve within a network? We have answered all these questions in this ultimate guide to routers and their working style. Don’t worry. We will talk about different types of routers, including Wi-Fi routers.

Routers: What Are They and How They Work

Routers are network devices that forward data between devices within your network and the internet. They also serve the purpose of IP address allocation and security. A router is different from a modem because it cannot convert fiber/telephone signals into digital signals.

What is a Router?

In the context of networking, a router is a network device that routes data between multiple devices in a network. This network could be a Local Area Network or something larger like the Internet. A router is crucial in helping your smartphone, laptop, or any other internet-connected devices to access the network. Based on the requirements and context, you can find multiple types of network routers.

A Wi-Fi router is one of the most common options for these days. These routers are used to set up a wireless (Wi-Fi) network that provides internet access to all Wi-Fi-enabled devices. A Wi-Fi router does not require an internet connection. You can get the benefits of a wireless network even if you have not connected the network to the Internet.

The most significant purpose of a router is to enable seamless communication between devices within your network. For instance, you cannot enable a network printer without a router. The second function is to assign IP addresses and ensure security while doing so. Routers are also responsible for finding the most efficient data routing paths. We will talk about these functions in detail later.

Even though many use Router and Modem interchangeably, both are different. A modem is responsible for converting fiber/telephone signals into digital signals, whereas a router deals with digital signals in the first place.

How Does a Router Work?

Before I tell you how a router works, a quick overview of a network is necessary. For the time being, we shall consider the case of the Internet alone. Here’s how multiple devices from your network interact with a larger internet connection.

A router works as the mediator between your devices and the internet. When you make a request from your PC or smartphone, the router will forward the request to the Internet, which involves multiple elements like DNS and IP addresses. While doing so, the router will also assign an IP address to your device. This IP address will be your device identifier for (at least) the session. Now, when there is a response from the Internet, the router will strategically forward the data to the corresponding device.

The core purpose of the router deals with this strategy.

Whenever there is a response from the internet, the router must decide where the data should go. In order to understand this, the router must keep a Routing Table, which is a complicated list of devices within your network. This process of forwarding the data between devices and the Internet would take place numerous times within a second. Therefore, a router should have the necessary processing power and RAM to manage these tasks.

In a simpler analogy, you can think of a router as a super-intelligent mail carrier. This mailman will work within your network and understand where the mail (data packets) should go. Whenever you get a mail back, the mailman will understand your address and get it back to you. Just like a mailman is necessary for the mailing system to work, a router is required for internet transactions to function well.

Router Functions

We already talked about the core functionalities of a router in a network. We shall now look at the different functions of a router.

Data Routing

Routing data between multiple devices within a network is the primary function of a router. A router would receive and forward numerous packets of data between these devices, creating a seamless multi-device Wi-Fi or Ethernet network. Without this active routing process, multiple devices cannot connect to a network and enjoy the benefits.

Security

While receiving and forwarding these requests and data, routers also take care of security and privacy. To make this possible, a router may use multiple firewalls and security protocols. A firewall will prevent third-party entities from connecting to the network. On the other hand, security protocols will ensure that your network transactions are encrypted and secure.

Network Management

Depending on the network size, routers also take care of network management. For instance, not all devices require the same bandwidth or traffic priority. A router will identify these differences and route the data in an optimized manner. You also get access to some Quality of Service features. These QoS features require an additional layer within the router.

Connecting Devices

Finally, a router allows the different devices within your network to interact with each other. We are talking about devices like printers, scanners, Wi-Fi speakers, etc. This way, all these devices will stay in the network, and you do not have to connect all devices separately. Without a router, you cannot enjoy these benefits anymore.

Types of Routers

Not all routers are made the same; for the same reason, not all networks are made the same. So, depending on the network size and purpose, you may find different types of routers in the market.

Core Routers

Large-scale networks such as the ones maintained by your ISP need a core router. These devices work within a Local Area Network, determining which traffic goes where. In terms of performance, core routers are at the top, offering maximum control as well. You would not need a core router in residential spaces. However, you may want to consider one if you set up network infrastructure for a large office space.

Edge Routers

Another essential part of the Internet infrastructure, an edge router, is responsible for connecting a LAN to an external network, such as the Internet. However, these edge routers are also very powerful, meaning that residential customers do not require these devices. In a network environment, you can find more than one edge router.

Distribution Routers

Distribution routers, as their name says, are responsible for distributing the information within a network. It may happen between a wired and wireless network or vice versa. For instance, a distribution may get the data from an edge router and make the information available to different devices within your network. These routers may work over Ethernet or Wi-Fi.

Wireless Routers

Wireless routers, better known as Wi-Fi routers, use Wi-Fi to router data packets over a wireless network. It creates a Local Area Network in which devices are connected wirelessly. A wireless router is a distribution router at its core, but this one is designed to work over Wi-Fi. However, in most cases, a Wi-Fi router would also have multiple LAN ports, allowing you to connect Ethernet devices.

Virtual Routers

Virtual routers are similar to the other types of routers I have mentioned above. However, unlike those core hardware devices, virtual routers work at the software level. They make use of virtualization and create virtual networks within a physical network. These virtual networks can then be utilized for multiple purposes with increased security.

Mesh Routers

Mesh routers are Wi-Fi routers that are used for large spaces. Usually, you may need multiple routers and networks to offer network coverage over a large space like a multi-story building or an office. However, you can use a mesh router to enable a space-wide network that offers seamless roaming. You can connect your devices to a single SSID instead of multiple networks and enjoy network-based benefits.

You can also find additional sub-types of routers, such as dual WAN routers. Nowadays, ISPs also provide a combination device, which contains a modem and a router.

Modems vs Routers

Let’s take a quick look at the differences between a modem and a router.

A modem is an intermediary device that converts fiber/telephone/coaxial signals into digital signals that your computers and other digital devices can understand. A modem is also known as a fiber unit these days. A LAN cable from the modem could be used to set up a wireless network using a router.

A router, on the other hand, is responsible for routing information within an existing network. It cannot be used to convert telephone/fiber signals into digital signals. Therefore, if you want a complete solution to set up an internet connection, you must go for a modem, not a router.

Combined Devices

These days, ISPs also come up with combined devices. These devices function like modems and routers at the same time. This way, you have to power on and connect only one device instead of two. One significant limitation is that these combined devices may have shared system resources. Therefore, processing power for the router/modem may not be enough at times.

However, with separate devices, you do not run the risk of insufficient resources. However, you need to set up multiple power sockets and cables. You would also need various power backup systems, depending on where you live.

Frequently Asked Questions

Conclusion

I believe this guide answered at least some questions you had about routers and how they work. You might only have to deal with Wi-Fi routers in your life, but it is better to know how they work. And you might want to consider the other router options if you ever want to improve your network infrastructure.

When I upgraded my home office infrastructure, I had to get an additional distribution router. This became necessary considering the high number of network devices I had at home. Otherwise, you can make do with a single router and a few access points.