Describe a router.

One or more packet-switched networks or subnetworks can be connected using a router. By sending data packets to their intended IP addresses, it manages traffic between different networks and allows several devices to share an Internet connection.

Although there are many different kinds of routers, the majority of them transfer data between LANs (local area networks) and WANs (wide area networks). A LAN is a collection of linked devices confined to a certain region. Typically, a LAN needs just one router.

In comparison, a WAN is a sizable network dispersed across a significant geographic region. For example, large organisations and businesses with several sites across the nation will require individual LANs for each location, which connect to the other LANs to form a WAN. A WAN frequently requires numerous routers and switches due to its wide distribution.

*A router transfers data between separate networks, whereas a network switch passes data packets between groups of devices in the same network.

How is a router operated?

Consider a router as an air traffic controller, and consider data packets as planes flying to various airports (or networks). Each packet must be sent as quickly as possible to its destination, just as each plane has a distinct destination and travels a distinct path. A router assists in guiding data packets to their intended IP address, just like an air traffic controller ensures that aircraft reach their destinations without getting lost or experiencing significant disruptions on route.

An internal routing table, which is a collection of routes to different network destinations, is used by a router to effectively guide packets. The router first analyses the header of a packet to establish its destination before consulting the routing table to determine the fastest route there. The packet is subsequently sent to the following network along the route.

Read What is routing? to discover more information about IP routing and the protocols involved.

How are routers and modems different from one another?

A router and a modem may be combined into one device by certain Internet service providers (ISPs), but they are not the same. Each participates in a unique but equally crucial function in tying networks to the Internet and one another.

While a modem links those networks to the Internet, a router establishes the networks and controls the data flow inside and among them. By transforming signals from an ISP into digital signals that can be understood by any connected device, modems create a connection to the Internet. To connect to the Internet, a single device can plug into a modem; alternatively, a router can assist spread this signal among several devices connected to an existing network, enabling all of them to connect to the Internet at once.

Consider this: If Bob has a router but no modem, he can still set up a local area network (LAN) and transport data among the connected devices. He won’t be able to link that network to the Internet though. Alice, on the other hand, just has a modem. She’ll be able to use one device to access the Internet (like her laptop for work), but she won’t be able to share that Internet connection with several devices (say, her laptop and her smartphone). Carol, on the other hand, has a modem and a router. She can connect her desktop computer, tablet, and smartphone to the Internet simultaneously by creating a LAN using both of her devices.

What are the many router types?

A router must first talk with a modem in order to connect a LAN to the Internet. There are primarily two methods for doing this:

• Wireless router:

To connect to a modem, a wireless router utilises an Ethernet connection. Data packets from binary code are transformed into radio signals, which are then wirelessly transmitted via antennas. Instead of establishing LANs, wireless routers build WLANs (wireless local area networks), which use wireless communication to connect a number of devices.

• Ethernet router:

Similar to a wireless router, a wired router connects to a modem using an Ethernet connection. After that, it establishes a LAN and connects the network’s devices to the Internet using various cables to connect to one or more of the network’s devices.

There are several other specialised types of routers that perform certain roles in addition to wireless and wired routers for small LANs:

• Central router:

A core router is used by major firms and enterprises that transfer a huge amount of data packets within their network, in contrast to the routers used within a household or small company LAN. Core routers don’t interact with other networks; they work at the “core” of a network.

• Border router:

An edge router connects with both core routers and external networks, in contrast to a core router, which handles all data traffic inside a big network. Edge routers operate at the “edge” of a network and communicate with other LANs and WANs using the BGP (Border Gateway Protocol).

• Online router:

A virtual router is a piece of software that serves the same purpose as a typical router in terms of hardware. If one fails, it might set up a primary and backup virtual router using the Virtual Router Redundancy Protocol (VRRP).

What are some of the security issues that routers face?

• Exploiting vulnerabilities:

Firmware, which is automatically installed on all hardware-based routers, aids in the operation of the router. Like any other piece of software, router firmware frequently has flaws that hackers might take advantage of, and router manufactures frequently provide updates to fix these flaws. This calls for routine firmware updates for routers. Attackers may get access to unpatched routers and use them to monitor traffic or incorporate them into a botnet.

• DDoS assaults:

The network infrastructure of both small and big companies is frequently the subject of distributed denial-of-service (DDoS) assaults. DDoS assaults at the network layer that are not mitigated might overwhelm routers or make them malfunction, causing a lag in the network. One method for shielding routers and networks from these DDoS assaults is Cloudflare Magic Transit.

• Administrative qualifications:

Each router has a set of admin credentials that may be used to carry out administrative tasks. The default values for these credentials are “admin” as the username and “admin” as the password. Attackers are aware of the typical default values for these credentials and can use them to remotely control the router if they are not changed. As soon as feasible, the username and password should be updated to something more secure.