Modem vs Router Differences and How Does it Work Together

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People often get confused when they hear the router and modem, but both the router and modem differ in core functionality.

The router and modem are found on the same traffic line next to each other in the same network structure.

Modem act as the first device which receives internet traffic in a network, and next, it goes to the router to redirect the traffic to the appropriate end devices.

Let’s look into the difference between modem and router.

What is Modem, and how does it work?

A modem is a device that converts an analog signal received from ISP (Internet service provider) to a digital signal, which devices like computers and vice versa can understand.

In other words, we can say that modem act as a bridge between your local or internal network and the external network such as the internet.

how does router and modem works

How does the modem work?

The term modem is derived from two words, modulation and demodulation, which tells how the modem works.

In computer networks, the term modulation is the process in which it converts (modulate) digital data into an analog signal, which is further transmitted over a telephone line.

On the other hand, the term demodulation is the process that converts (demodulate) the received analog signal into a digital signal.

Moreover, the type of internet connection will depend upon how your modem is connected. The internet connection can be cable, telephone, satellite, or fiber.

The type of modem depends on your ISP infrastructure to successfully communicate with your Internet service provider.

Most modems consist of three important ports, one port is connected to the internet, another port is connected to your router or device, and the last one is used for the power supply.

A modem transmits a signal over a telephone line in the past, which provides a data speed of 56kbps.

With the advancement of technology, the signal can now be transmitted over cable or fiber-optic connection, which provides much better speed.

What is a Router, and how does it works?

A router is a networking device that routes (or distribute) your network traffic from the modem to the connected devices in your network.

It allows devices to communicate with each other in a network and lets you connect with the internet or external network.

Additionally, most routers also come with built-in switches that let you connect multiple wired devices.
Also, most modem comes with a wireless radio that let you connect with wireless devices.

router and modem differences

How does the router work?

Understand router as that which sits in between your home network and the internet.

The home network can have multiple devices that would like to communicate or connect with the internet. It may include a computer, mobile phone, smart tv, and other wireless or wired devices.

So, it doesn’t matter how many devices are connected to the router; it will come from a single device for the internet.

The router also assigns an IP address to all network devices to distribute internet traffic to the correct device.

Moreover, the router also keeps track of the traffic that goes to each device in a home network.

The router helps you to enable security settings such as firewall, prioritize and customize internet traffic and much more.

Every router consists of multiple Ethernet ports that let you connect with multiple devices in a network. The one Ethernet port of the router goes to the modem, which lets you connect with the internet.

You cannot connect with the internet only with the router because you need to transmit digital data over the type of internet connection you have. Here comes the role of the modem.

Do you need a modem or a router?

You require both a router and a modem to connect with multiple devices in a network and with the internet. Moreover, you connect devices either through a wired or wireless medium.

The most modem comes with only one Ethernet port that allows you to connect with only one device in a network.

Also, the modem doesn’t provide you with any security features, and you cannot control your traffic inflow and outflow.

Similarly, a router alone cannot connect with internet services; you need a modem for this.

The modem and router need to be connected if you want to access internet services and distribute them to multiple devices.

But, nowadays, you don’t need to buy a separate modem and router. These days, you will get a single device that comes with both a modem and router.

Modem vs. Router Differences you need to know.

Modem lets you connect with the wide-area network (WAN) such as the internet, whereas router lets you connect with the local area network (LAN) or Wifi network.

The router act as a central hub to all the devices in the home network (LAN) and the modem is the gateway to the internet.

Modem transforms digital data into an analog signal and vice versa. In contrast, the router distributes the internet traffic from the modem to the connected devices. Further, it collects the traffic from multiple devices to be sent back to the modem.

You may find both the device appear to be very similar, but the router often comes with an external antenna and multiple Ethernet ports.


Router and modem: both perform different functions and can be confusing to most of them.

You need to understand how two different devices work and how two devices carry out traffic flow.

The modem is a must for any device because it is a gateway to the internet. Most modern devices come with an in-built modem.

If you want to connect to internet services, then a router cannot work without a modem, but a modem can work without a router.

Nowadays, a single device can perform the functionality of both the router and modem. So, no need to buy separate devices.