Difference Between Modem and Router (With Table)

No part of our life left untouched from the internet. We are living in a digital era and surrounded by various digital devices that are running with the help of the internet. How many of us know the underlying architecture of the internet? or How many do we know how we connect with the internet? Only a few.

The Internet has become an inevitable part of our world but its underlying architecture is a little complex system but this doesn’t mean one needs to learn or comprehend to access it. But having a basic understanding of a few terms can actually help to discover how’s & why’s of this wonderful connect.

Modem vs Router

The difference between Modem and Router is that Modem stands for “Modulator-Demodulator”, is a hardware component that helps the computer or any other network device to connect to the internet.

Modem converts the analog signals from cable wire or telephone to digital data through modulation so that connected computers can understand the same and in reverse demodulates the digital data to analog signals so that the same can be sent back to standard phone lines.

A router is a hardware device that routes the data within or from one local area network to another network. Router authenticates the user or connected machines and allows connection between them only.


Comparison Table Between Modem and Router (in Tabular Form)

Parameter of ComparisonModemRouter
DefinitionA Modem is hardware that modulates the analog signal from phone or cable to computer and demodulates from computer to phone or cable.A Router is hardware that is used to connect or routes the data within one or multiple local area networks.
PurposeIt is a device that carries the information from the internet to your local area network.It is a device that routes the information to the respective computer connected to the local area network.
Internet AccessModem is required to access the internet as it connects your local area network to the internet service provider.Router is not essential to access the internet.
ProcessModem receives the analog signal from telephone and modulates it to digital form i.e. β€˜0’ or β€˜1, and demodulates from digital to analog.Router routes the data packets to the respective computer basis the IP mentioned on their header.
Operation Layer in OSI ModelData Link.Physical Layer, Data Link Layer, Network Layer.
Cable UsedRJ45 for Router and RJ11 for Telephone.RJ45 for the computer.
SecurityModem transfers the data without any authentication and check, thus no security is assured.Router checks each data packet through the information saved on its header and then only transfer the same. Thus, security is ensured.


What is Modem?

Modem act as a communication bridge between your LAN (local area network) and the internet.

Modem stands for modulator-demodulator means it modulates the analog signals from telephone lines to digital bits form (‘0’ or ‘1’) so that it can be easily encoded and transferred from the sender computer.

And on the receiving end, it demodulates the digital signals to analog and decoded.

It can be connected to any infrastructure i.e. telephone, cable, fiber, or satellite, which further provides the standard Ethernet cable output that you can either connect with your individual computer or to any router to access the internet.

A unique IP address is provided by the ISP (internet service provider) to your LAN that is assigned to it and used to connect the internet. In the OSI model, the modem operates on the data link layer.

Apart from fiber optic, a modem is essential to access the internet. The types of modem exist are Dial-up, DSL (broadband modem), Cable modem, and Mobile broadband.

The modem doesn’t ensure security as it only transfers the packet or information as it is received.


What is Router?

A router is a device that is used to connect or routes the data within one or multiple local area networks.

It routes the data packets to their respective destination using the IP address mentioned on the data packet header.

The router is used to connect two LANs or WANs or LANs and WANs. The router is used only to distribute the data packets to one particular computer.

RJ45 cable is used in the router to connect the computer with the network.

Security is ensured in the router as it screens each data packet received and passes it to the recipient only if it is ok and then after identifying the physical address routes it to the specific destination.

Thus it saves the computer and network from potential threats or harmful attacks. The router is not essential to access the internet.

In the OSI model, the router operates on the physical, data link, and network layer.

Main Differences Between Modem and Router

Knowing the difference between Modem and Router helps us to understand the technical terminology as well as their actual purpose and functioning,

  1. A modem is a device that modulates and demodulates the signals i.e. from analog to digital and digital to analog, whereas a router is a device that is used to connect or routes the data within one or multiple local area networks.
  2. A modem converts the signals in the form of data packets from the internet to the local area network and vice-versa, whereas a router scans, analyzes and distributes the data packet to route them to their respective destination or recipient computer or network.
  3. The modem works on the data link layer of the OSI model, whereas a router works on physical, data, and network layers.
  4. The modem doesn’t validate and screen the information coming in the network, thus poses a threat to the network, whereas a router screens the data packet and basis the mentioned IP address in the header routes them to the respective destination, thus, secured enough.
  5. In modem, RJ45 is used to connect the router and RJ11 for the telephone line, whereas, in a router, RJ45 is used to connect the computer networks.
  6. A modem is necessary for internet connectivity, whereas a router is not essential to access the internet.



The Internet is an undeniable need in today’s time at personal as well as professional front.

From buying groceries to booking travel tickets or from attending meetings via video-conferencing to imparting online classes, everything is possible through the internet.

The location has become irrelevant as no matter where you are, you can do whatever you want to through the internet. But to access the same you need installation of some devices i.e. Modem and Router.

As new technologies are knocking the doors every day, some of the ISPs are offering integrated devices that combine the functionality of modem and router in one single device.



  1. https://www.computerhope.com/jargon/m/modem.htm
  2. https://www.lifewire.com/what-is-a-router-2618162