Difference between Modem and Router

by Shubham Khurana

The terms modem and router are often mistakenly used as synonyms, although they are very similar in many ways and have hardly any important differences for the normal consumer. However, there are significant differences between the two devices, but most of them require explanation. 

Everyone knows somehow; this has to do with the black box that brings WiFi into the house and then sends it to a computer or other device. But how does it work? What is the difference between a modem and a router?

The Modem

It all starts with a modem. It is the bridge between the huge Internet and your home network. Actually, the modem is just an abbreviation. It's called a modulating-demodulator, and it modulates digital signals so they can be sent over the telephone line. Today there is broadband, everything is a little different, but the name still exists.

Internet enters the house through a cable, and some wall has a socket with a strange-looking connection. The modem is connected via a LAN cable. You can also connect your computer directly to it.

Because the modem processes your ISP's signal, you must use a modem that is supported by your ISP. Not all modems are suitable for all providers. You can buy it from a provider or check their website to find out which modem models are compatible and then buy it yourself or reuse the old modem from the old house when you move.

A modem works with digital data within an analog line compared to a router. On the other hand, routers are used for network communication between multiple devices.

  • A modem is used, for example, to receive and process analog signals such as communication networks, which can be both telephones and cable TV.
  • Unlike routers, modems handle digital data on analog lines. For example, the analog communication network is a telephone network or cable TV.
  • The modem generates suitable signals in the high-frequency range and then sends these signals onto the line.
  • For this purpose, the modem generates the appropriate signals and then sends them to the line. Therefore, the device converts analog signals to digital signals. On the other hand, the router sends out a permanent digital signal.
  • In short, a modem is used to receive analog signals and convert them to digital signals.
  • For example, a modem is used for logging on to the Internet.

Of course, you can also operate multiple routers on your network.

The Router

Modem after receiving signals and data from the Internet, it still needs to be distributed via WLAN. This is the job of the router. The English word route means to send or control. The router controls the data traffic between the modem and all end devices connected to the WLAN network.

The WiFi router

  • The WiFi router is a computer network as well as the Internet. Depending on your point of view, this will couple or separate multiple computers from each other. The device analyzes incoming data packets based on their destination address, forwards them, or blocks unwanted data.
  • If the packet is forwarded, it reaches the connected end device. These can be routers, computers, or other technical equipment. Transmission can be done via a LAN cable or wirelessly via WLAN.
  • Router permanently sends digital signals to ensure communication between different devices on the network.
  • The router analyzes the data packet and forwards it to the corresponding destination address. 
  • Routers can communicate with each other and can also be terminal devices such as smartphones and laptops. 
  • Data packets can also be blocked by routers and are generally forwarded via LAN or WLAN. 
  • Through a router, you can create a network that transmits existing digital Internet signals.
  • In short: With one router, you can connect multiple computers to the network. Alternatively, you can also use the device as a repeater (signal amplifier) to improve your WiFi signal.

Tip: If the Internet speed is too slow, there may be too many devices connected to the router at the same time. For example, if your connection speed is 100 Mbps, it means that the speed on the connector can reach 100 Mbps, not on all devices.

Therefore, the router is the reason why, despite only a single connection to the Internet – the socket in the wall – we can connect many different devices and surf the Internet with them at the same time.


Most private homes have a combination device. That is why it is difficult to find the difference between a modem and a router because we usually do not see it in the box.