Packet Switching

Many of the files we send over a network are far too big to be sent in one go. Instead, we break them down into smaller manageable units called packets.

When receiving, for example a website, the website will be able up of thousands of individual packets

Each packet contains additional information to support the data being received and reassembled in the correct order.

• Sequence number
• Checksum
• Type of packet
• Addresses (sender & destination)

This data is stored in the header

Packet Switching

When sending packets over a network, or the internet, a series of steps take place. The below example using a webpage outlines the steps.

1. You request a webpage
2. The web server receives the request via the internet
3. The webpage is broken down into smaller parts (packets)
4. The packets are sent across the internet to your IP address. These packets may take different routes and arrive in a different order to that they were sent
5. Your computer reassembles the packets into the website.
6. If any packets are missing your computer requests the missing data.