Packet switching is a method of transmitting data over a digital network. Unlike circuit switching, which establishes a dedicated physical connection between sender and receiver, packet switching breaks down data into smaller units called packets. These packets are then transmitted independently across the network and reassembled at the destination.
How Packet Switching Works
Data Segmentation: The sending device divides the data into packets. Each packet contains a portion of the original data and a header.
Packet Header: The header includes information such as the source address, destination address, sequence number (to ensure correct reassembly), and error detection codes.
Routing: Packets are sent across the network. Each router examines the destination address in the packet header and forwards the packet towards its destination. Packets may travel different routes to reach the destination.
Reassembly: At the destination, the packets are received. The receiving device uses the sequence numbers in the packet headers to reassemble the packets in the correct order, reconstructing the original data.
Key Advantages of Packet Switching
Efficient Use of Network Resources: Multiple users can share the same network links simultaneously. Resources are used only when packets are being transmitted.
Robustness: If one route is congested or unavailable, packets can be rerouted via alternative paths.
Flexibility: Packet switching is well-suited for data networks like the Internet.
Key Disadvantages of Packet Switching
Variable Delay: Packets may experience different delays depending on the network conditions and the routes they take.
Overhead: The packet headers add overhead to the data being transmitted.
Complexity: Requires more complex network devices (routers) compared to circuit switching.
Stage
Description
Data Segmentation
Data is divided into packets.
Header Addition
A header is added to each packet containing addressing and sequence information.
Routing
Packets are routed independently across the network.
Reassembly
Packets are reassembled at the destination in the correct order.
Figure:Suggested diagram: A diagram illustrating data being divided into packets, each with a header, being sent across a network with multiple possible routes, and then reassembled at the destination.
Packet switching is the fundamental technology behind the Internet and other modern data networks. Its ability to efficiently utilize network resources and provide robustness has made it the dominant method of data transmission today.