What is Router?

Before we start, we must know....

Sub-network: A sub-network is a constituent network of an internetwork for example a LAN.

End-system: An end-system is a device used to support user applications, usually on a LAN, or, more specifically, part of a sub-network.

Intermediate System: A device that allows two sub-networks to communicate. Such a device is known as a router and permits communication between different network types.

What Are Routers?

• If we have to establish a connection between two communicating systems then to establish a
•  connection between them we use routers at both ends which we connect through fiber optic cable of high bandwidth.
• 
  
• By this scenario, the traffic in the form of data, voice or video will flow from both ends dedicatedly between 
• them without the interference of any third unwanted traffic. This process is cost-effective and time-efficient.
• 
  
• So, this router also plays a vital role to establish connections between them.

Types Of Routers

There are basically two types of Routers:

Hardware Routers: 

• These are the hardware with distinctive in-built software competence provided by the manufactures. 
• They use their routing abilities to perform routing. 
• They have some more special features also in addition to basic routing feature.

For example:-Cisco 2900 router, ZTE ZXT1200 etc

Software Routers: 

• They operate in the same way as the hardware routers do, but they don’t have any separate hardware box. 
• Software routers are generally used as gateways and firewalls in large computer networking systems both types of routers have their own features and significance.
• The software routers have limited port for WAN connectivity and other port or card support LAN connectivity, therefore, they can’t take the place of hardware routers.
• Because of the inbuilt features of routing all the cards and ports will perform the WAN routing and other also depending upon its configuration and capacity.
• It works on the network layer of the OSI reference model and communicate with neighbor devices on the concept of IP addressing and subnetting.
• The main components of routers are central processing unit (CPU), flash memory, non-volatile RAM, RAM, network interface card and console.
• Routers have a different kind of multiple ports like fast-Ethernet port, gigabit, and STM link port. All ports support high-speed network connectivity.
• They have the capability to analyze the type of next link and hop connected with it which makes them superior to other layer-3 devices such as switch and bridges.
• Routers always work in master and slave mode thus provides the redundancy. Both routers will have the same configurations at software and hardware level if the master fails then slave will act as Master and perform its entire tasks. Thus saves the complete network failure.