• atulsharma.cse@gmail.com
• October 15, 2022
• No Comments

Networking is a comparatively less familiar field of networking, but one that is evolving rapidly as people are getting to know, how lucrative it is. Networking is a domain in the Information Technology landscape that has a very wide horizon when employment and levelling up are concerned. 

This domain of information technology has various components working simultaneously that make a topology and each has its importance for a designated function.
In this blog, we shall have a look at the working of a router in Networking. 

What is a router?

A router can be defined as a device that establishes a connection between two or more packet-switched networks or subnetworks. Routers can also be defined as networking devices that are operating at layer 3 or a network layer of the OSI model.

Primary functions of a router in Networking:

A router indeed performs many united functions at once, few of its primary functions are: 

1. It manages traffic between the networks by forwarding data packets to their intended IP addresses.
2. It also allows multiple devices to use the same internet connection. 
3. They also are responsible for receiving, analysing and further forwarding data packets amongst all the connected computer networks. As soon as the data packet arrives, the router begins the inspection of the destination address. 
4. The router consults, the received packets’ routing tables to decide the optimal route and then further begins to transfer the packets along that route.

What are routing protocols?

We saw the kinds of routers we have and routing techniques but now we must be aware of the routing protocols. Routing Protocols are referred to the set of defined rules used by the routers to communicate between the source and the destination. They are responsible for moving the information from the source to a destination, rather they only update the routing table that contains the information. Network Router protocols help a user to specify the way in which the routers can communicate amongst themselves. It also makes way for the network to select routes between any two nodes on a given system network.

Types of a router in Networking:

There are different routes in a router. A route can be defined as a pairing between a destination and the attributes of the path to that destination. Thus it also has the name path-vector routing. The routers further receive a vector that contains paths to a set of destinations. 

There are various different types of routers in Networking, a few of them are as follows: 

• Static 
• Default
• Dynamic

We shall now see them in detail: 

Static Routing:

Static routing can also be defined as a way of network routing technique. It is not necessarily a routing technique. Rather it is the manual configuration and also it selects a network route. It is most commonly administered by the network administrator.   It is employed in certain scenarios where the network parameters and environment are expected to remain constant.

This kind of routing is only optimal in a few situations. Network degradation, latency and congestion are some of the consequences that are inevitable due to the non-flexible nature of static routing.

Advantages:

• In this form of routing there exists no overhead on the router, or CPU. 
• In static routing, only the administrator is capable of adding routes. 
• There exists no bandwidth between links. 

Disadvantages: 

• It takes up excessive time, hence it isn’t advised for large organisations. 
• There is a need for the administrator to be aware of how each router is connected. 
• A link failure will lead to complete network failure, which doesn’t sit well, especially in small networks.

Default Routing:

An instance of default routing

• The default route is a route that is effective as soon as there is no other route available, for an IP destination address.
•  Whenever a packet is received on a routing device, the device begins to check and see if the IP destination address is on one of the device’s local subnets.

Advantages: 

• They establish routes that do not go down. 
• They are beneficial as they keep the routing tables small. 

Dynamic Routing:

Working in dynamic routing. 

•  Dynamic routing is defined as the technique of finding the best path for the data to travel over a network in this process, a router can transmit data through various different routes and reach its destination on the basis of conditions at that point in time of communication circuits.

Advantages: 

• It is advised for all large networks, as it is easier to configure. 
• In case of a link going down, this routing will enable, dynamically choosing a different route. 
• It enables a user to load balance within multiple links.

Disadvantage: 

• It happens to consume bandwidth as the updates are shared between the routers. 
• All the routing protocols are bound to put an additional load on the router, CPU or RAM. 

The basic components needed to route:

There are basically four important components of a router. The ones that have been identified as important are as follows:

1. Input ports:
These ports perform the physical layer function of terminating a physical link that is incoming at a router. 

2. Output Ports:
These ports store packets that are received from the fabric. Then these packets are further transmitted on the link that is outgoing.

3. Switching Fabric:

This establishes a connection between the router’s input ports to its output ports.

3. Routing Processor:
The routing processor works to execute routing protocols, maintain routing tables and link state information. It also is responsible for computing the forwarding table.

The functions of a router’s control plane functions are usually implemented in software and further executed on the routing processor.