Routing and Switching are an integral part of any computer network. To know about the functions and uses of routing and switching let’s first know about what are routers and switches.
Routers and switches both are networking devices which are used to connect the different devices in single or multiple networks. Routers are intelligent devices that carry and transfer data across multiple networks. On the other hand, the switch is less intelligent compared to the router as it only carries and transfers data within one network.
The major difference between routers and switches is that switches are used only in Local Area Networks (LAN) and are used to connect various devices in a single network. Whereas routers are used in Local Area Networks as well as Metropolitan Area Networks (MAN) and are used to connect devices within a network or connect multiple networks
What is Routing?
Routing in simple terms means directing someone or something on a particular path to a particular destination. Routing in Computer Networks is a process of selecting the best path to send the data in one or multiple networks. The router is an intelligent device that is specialized to take internet routing decisions in one or multiple networks. Routers have the main role of sending the data packets through the best path possible to send the data packets in the quickest and easiest path.
For Example: Consider a router an air traffic regulator and information parcels as airplanes go to various airports (computer networks). Similarly, as each plane has a special objective and follows a distinct route, every parcel should be directed to its endpoint as productively as could be expected. Similarly, an air traffic regulator guarantees that planes arrive at their endpoints without getting lost or experiencing a significant disturbance en route, a router guides information parcels to their endpoint IP address.
What is Switching?
Switching in simple terms means exchanging or changing something’s position, direction or focus. Similarly, in a computer network, switching means transferring the data from one computer network to another computer network. In computers, network switching is done by using a hardware device called a switch.
For Example: Consider the switch as a postman who picks up a packet with the destination address (MAC address in networking) on it from the post office (client computer) and delivers the packet to the destination address.
Functions of Routing:
Routing takes place in the network layer of the OSI model. The router is used in Local Area Network as well as in Metropolitan Area Network. In routing, data is sent in the form of packets. There are two main functions of routing are as follows:
1. Path determination:
Routing tables and network addresses transmit packets via the network. The technique of routing includes determining the superior route through the network. Routers do this by way of using a routing protocol to communicate the network facts from the router’s routing table with neighbouring routers.
2. Packet Forwarding:
Packet Forwarding is the basic way of sharing information across the systems on the networks. Packets are transferred between a source and the destination ports. The interface with the destination IP address that is specified in the packet headers then retrieves the packets from the local network.
Functions of Switching:
Switching takes place in the data link layer of the OSI model. Switching can be used only for Local Area Network. Following are the functions of Switching:
Switch is responsible for controlling the transmission of frames between switch ports connected via cable using traffic forwarding rules. Traffic forwarding depends on address learning. Switches settle on traffic sending choices in light of the 48-bit media access control (MAC) addresses utilized in LAN guidelines, including Ethernet. For working this out, the switch learns where are the clients in the network by looking at the source address of the frame received. The frame contains two addresses that are source address (address of the sender device) and the destination address (address of the receiver device).
Every port on the switch has a unique MAC address assigned to it. Each frame is sent and received on each port, so a specialized switching software gets the source address from the frame and stores it in the table of addresses that are maintained by the switch. This is how the switch automatically learns about the stations/clients that are reachable on different ports.
Forwarding simply means to send something onwards. In computer networking, forwarding means to pass the network traffic from one port of the network switch to the client computer or another device connected to another port on the switch. If the destination MAC address is found, the switch forwards the frame to the corresponding port of the MAC address. If the source MAC address is the same as the destination MAC address, the switch will drop the Ethernet frame. This is known as filtering.
In Local Area Networks, repeated links are created to avoid the failure of transmission of data due to the failure of any link. Spanning Tree Protocol (STP) is used to stop network failures but it does permit repetition. Different port states happen in STP, they are blocking, listening, learning, and forwarding.
Routers and switches are an integral part of any computer network for data exchange and communication in any organization. And the proper selection of the devices, installation, configuration, and maintenance of the same is more important than anything else for the smooth functioning of all the IT infrastructure in any organization.