In computer networks, data is not sent as a continuous stream but rather as discrete units called . A packet is a formatted unit of data used in communication. When large amounts of data (such as files, emails, or streaming videos) are transmitted over the network, the data is broken into smaller chunks called packets. These packets travel individually across the network and are reassembled at the into their original form.
The header contains control and addressing information used for routing the packet across the . It includes the Source IP Address, which is the IP address of the sender, and the Destination IP Address, which is the IP address of the recipient. Other important components are the Version of the IP being used, the Protocol which specifies the Layer 4 protocol, and the Time-to-Live (TTL), which limits the packet's by defining how many hops it can pass through before being discarded.
The actual data being transported by the packet is known as the . This can represent various types of information, such as a portion of a web page or a video file. Packet data size can vary widely, generally ranging from 20 bytes to bytes, depending on the protocol and MTU limitations. Fragmentation occurs when a larger packet is broken into smaller pieces (fragments) that fall within the MTU limits of the network. Each fragment contains a portion of the original packet's data along with its own information.
