What is Router? and Difference between Router vs Modem

21st September 2022 Harshvardhan Mishra

Whenever we talk about networking, you must have heard the names of modem and router. And will also be familiar with both these devices. When we plan to create a network in home or office we need these both devices. I am going to explain about modem and router both. Often we think of these two words as one and get confused.

What is a modem and Router?

In simple words, A Modem is just a networking device that is used by computers to connect your home network to the massive internet. While on the other hand, the router is a box that lets all of your wired and wireless devices use that Internet connection at once and also allows them to talk to one another without having to do so over the Internet.

In Technical terms, A Modem modulates and demodulates electrical signals sent through Fiber optical cables, coaxial cables, or other types of wiring. It means Modem converts digital information from your computer into analog signals that can transmit over wire network, and it can translate incoming analog signals back into digital information that your computer can understand easily. So We can say that A Modem just do two activity, Modulation and De-Modulation. Whereas, A Router’s decides route data between devices in your home, and between those devices and the wider Internet.

Definition of Router, A router is a device that connects two or more packet-switched networks or subnetworks. It serves two primary functions: managing traffic between these networks by forwarding data packets to their intended IP addresses, and allowing multiple devices to use the same Internet connection.

How does a router work?

A Router works as an air traffic controller and data packets as aircraft headed to different airports (or different types of network). Each plane is going to unique destination with unique route. Here Each packets needs to be guided to its destination as efficiently as possible. Now Here Router as a traffic controller ensures that each planes reach their destinations without getting lost or disruption along the way, a router helps direct data packets to their destination IP address.

In order to direct packets effectively, a router uses an internal routing table — a list of paths to various network destinations. The router reads a packet’s header to determine where it is going, then consults the routing table to figure out the most efficient path to that destination. It then forwards the packet to the next network in the path.

Difference between router and modem Modem vs Router

Generally some Internet service providers (ISPs) may combine a router and a modem within a single device, they are not the same. Each plays a different but equally important role in connecting networks to each other and to the Internet.

A router forms networks and manages the flow of data within and between those networks, while a modem connects those networks to the Internet. Modems forge a connection to the Internet by converting signals from an ISP into a digital signal that can be interpreted by any connected device. A single device may plug into a modem in order to connect to the Internet; alternately, a router can help distribute this signal to multiple devices within an established network, allowing all of them to connect to the Internet simultaneously.

Think of it like this: If Jack has a router, but no modem, he will be able to create a LAN and send data between the devices on that network. However, he will not be able to connect that network to the Internet. Alice, on the other hand, has a modem, but no router. She will be able to connect a single device to the Internet (for example, her work laptop), but cannot distribute that Internet connection to multiple devices (say, her laptop and her smartphone). Carol, meanwhile, has a router and a modem. Using both devices, she can form a LAN with her desktop computer, tablet, and smartphone and connect them all to the Internet at the same time.

What are the different types of routers?

In order to connect a LAN to the Internet, a router first needs to communicate with a modem. There are two primary ways to do this:

Wireless router: A wireless router uses an Ethernet cable to connect to a modem. It distributes data by converting packets from binary code into radio signals, then wirelessly broadcasts them using antennae. Wireless routers do not establish LANs; instead, they create WLANs (wireless local area networks), which connect multiple devices using wireless communication.
Wired router: Like a wireless router, a wired router also uses an Ethernet cable to connect to a modem. It then uses separate cables to connect to one or more devices within the network, create a LAN, and link the devices within that network to the Internet.

In addition to wireless and wired routers for small LANs, there are many specialized types of routers that serve specific functions:

Core router: Unlike the routers used within a home or small business LAN, a core router is used by large corporations and businesses that transmit a high volume of data packets within their network. Core routers operate at the “core” of a network and do not communicate with external networks.
Edge router: While a core router exclusively manages data traffic within a large-scale network, an edge router communicates with both core routers and external networks. Edge routers live at the “edge” of a network and use the BGP (Border Gateway Protocol) to send and receive data from other LANs and WANs.
Virtual router: A virtual router is a software application that performs the same function as a standard hardware router. It may use the Virtual Router Redundancy Protocol (VRRP) to establish primary and backup virtual routers, should one fail.

Reference – https://www.cloudflare.com/learning/network-layer/what-is-a-router/