Functions, types, and components of the network router

types of router. The router diagram shows cisco and edge router

A router is a networking components device used to connect two networks that use different protocols. It is mainly used as a gateway to connect the LAN and WAN or internet networks. They are used to direct traffic from source to destination by choosing the best path for the message. Network routers can be wired, wireless, edge, virtual, or core.

How router works

Routers sit between two different networks to help them communicate. Assume a computer in network A want to send a message to another computer that is in network B. The message will move from the source computer through the router which acts as a gateway to the other side. 

The router has a routing table that has different paths that it can assign to the message to reach its destination as fast as possible.

When the message reaches the router, it checks the message packet for the destination address. It then uses its routing table to assign the best path to its destination and forward the message to the next network component. 

The message is passed from one component to the next until it reaches its destination.

Functions of a router in computer networking

  1. Direct data packets from one network to the next
  2. It acts as a network gateway
  3. Uses the routing table to provide the best path for the data packets from source to destination
  4. Most routers have inbuilt firewalls and other security features that offer security for the devices within the network.
  5. They can be used to split big networks using sub-networks which increase the efficiency of the network and simplify network management.

Types of router

Networking routers come in different types depending on where and how they are used and the load they can handle. Some of the most common types of routers are as follows.

Wireless router

These are the most common routers that are used at home or in offices. It has a connection that connects it to a wired network and then it has capabilities to broadcast the internet to the wireless devices. It connects devices such as laptops, smartphones, and desktops that can access wireless networks. The wireless router has an antenna that helps send and receive signals.

Core router

This is a router that is used mostly by big internet service providers to link different clients. They offer very fast connections to other routers within their client locations. It works at the backbone of major network connections. Small companies and individual users may not require to have a core router.

Edge router

This is a router that is used to connect to other routers and switches. The edge router sits at the edge of the core networks. It is used after the core router to link the external network to the organization network. They act as gateways to the organization network and WAN/internet.

Wired router

This is a router that is connected to the devices that it serves via a cable. They don’t support wireless broadcasting of signals.

Virtual Router

These are software that is designed to take the physical function of a router. They can be used to forward packets, route messages, and security features among other functions of routers.

Components of a router

For a network router to function as expected it has different components that help it achieve that. The main components among others are:

  1. Processor: Router does a lot of data processing by determining different routes and the security of the network. To achieve this it has a processor for processing its data.
  2. Flash memory: this is the memory where the router operating system is stored. When the device boot from the ROM it passes control to the OS that is in the flash memory.
  3. Non-Volatile RAM (NVRAM): the memory is used to save the router settings after the user has made any changes. When the user makes any network setting on the router they are saved on this memory. Even when the device is powered off it still retains the settings.
  4. RAM: the router has a main memory that loads the router OS and data that is currently being processed. When you make changes to the router make sure you save them. This moves the settings from RAM to NVRAM which is nonvolatile.
  5. ROM: it is used to store the bootstrap for the router. It is like the BIOS ROM of a computer.
  6. Console connector: this is a connection that is used when the user what to make changes to the router. The console login allows for more administrator right to be able to set the device.
  7. Network Interface Card (NIC): being a networking component the router has a network card that is used to link the device to other media and other devices. You can learn more in this article about the types, functions, and components of network interface cards.
  8. Ethernet port: the device has many ethernet ports to connect to the terminated ethernet cable. The cable from these ports can connect to other routers within the network, switch, access point, or directly to the computer.