Difference between Router and Modem

Both Routers and Modems are network connecting devices. Routers work at the network layer and are responsible to find the shortest path for a packet, whereas Modems connect a device like desktop, laptop to the Internet. Routers connect devices across multiple networks.

Read through this article to find out more about Routers and Modems and how they are different from each other.

What is a Modem?

A modulator-demodulator, or a modem, is a piece of hardware that transforms data from a digital format designed for direct communication between devices using specific cabling into a format suitable for transmission via telephone lines or radio.

A modem encodes digital information for transmission by modulating one or more carrier wave signals, then demodulates signals to decode the delivered data. The objective is to create a signal that can be readily transferred and consistently decoded to recreate the original digital data.

Modems may be used with nearly any analogue signal transmission method, including light-emitting diodes and radio. A typical modem converts a computer's digital data into a modulated electrical signal for transmission over telephone lines, which is then demodulated by another modem at the receiver side to retrieve the digital data.

What is a Cable Modem?

A cable modem is a type of network bridge that uses radio frequency channels to allow bi-directional data communication across a hybrid fiber-coaxial (HFC), radio frequency over glass (RFoG), or coaxial cable infrastructure. Cable modems are generally used to offer cable Internet access, which uses the high bandwidth of an HFC and RFoG network.

Cable modems comply with IEEE 802.1D for Ethernet networking in network topology (with some modifications). Cable modems connect a customer's LAN to the coax network by bridging the Ethernet packets. It is technically a modem since it must modulate data to send it over the cable network and demodulate the data received from the cable network.

What is a Router?

In networking, a router is referred to as a connecting device. It is used to find the shortest path for a packet to reach its destination. The goal of a router is to connect many networks at the same time.

Routers operate on the network layer, but also on the physical layer and data link layer of the OSI (Open Systems Interconnection) architecture.

Unlike a firewall, routers do not incorporate encryption before routing the networks. Routers do not defend the network from dangers, but they do have a sharing feature that allows many networks to share an Internet connection.

How Does a Router Work?

A router is connected to two or more data connections from different IP networks. When a data packet arrives on one of the lines, the router evaluates the network address information in the packet header to determine its destination. The packet is then directed to the next network on its path using the information in its routing table or routing policy.

  • A router determines a packet's destination or target IP address, and forwarding tables and headers determine the best way for transmitting the packet.
  • A packet is passed from one router to the next via the networks that make up an internetwork (such as the Internet) until it arrives at its destination node.
  • Routers are most commonly used in the local area network (LAN) and wide area network (WAN) domains.
  • Routing protocols are used to transport data across the network.

Routers are far more expensive than other network equipment such as hubs, switches, and routers. D-Link, Cisco, and Nortel are some of the companies that manufacture routers.

Difference between Router and Modem

The following table highlights the major differences between a router and a modem.

Key Router Modem
Objective The primary objective of a Router is to connect various networks. The main objective of using a Modem is to connect a laptop or any device to the Internet.
Action Routers check the data packet and verify their path to the destination network device. Modems convert digital signal of laptop to analog signal and vice versa.
Action Routers distribute the requested data to the PC/Laptop. Modems get the requested data from the Internet to the PC/laptop.
Decoding Routers do not decode the signals. By decoding the ISP signal, modems conduct signal decoding.
Net Access It is not mandatory to have Routers to access the Internet. Modems are essential to access the Internet. Modems link your device to your Internet Service Provider.
Location A router is a device that connects electronic devices to a network. Modems can be connected directly to the computer or between the phone line and the router.
Layer Routers work in the Network layer. Modems work in the Data Link layer.


From the above discussion, we can conclude that Modems are electrical devices that transform the digital signals from your laptop to analog signals and vice versa, whereas Routers are the network devices that can connect multiple networks together. Routers examine the data packets and verify their path to the destination PC.