Network packet

A formatted unit of data carried across a computer network, combining payload with control information such as source and destination addresses. Packets let networks divide, route, and reassemble larger communications.

Internet Protocol: A family of protocols that carries datagrams between networks using logical addresses. IP supplies the addressing and forwarding rules used by many network packets.
Packet header: The control-information portion of a packet, typically placed before its payload. Header fields carry addressing and handling information alongside the packet's data.
Internet Protocol version 4: The fourth version of the Internet Protocol, using 32-bit addresses and IPv4 datagrams. IPv4 defines a widely deployed packet format and its header fields.
Network frame: A link-layer unit that packages data for transmission over a particular network medium. Frames carry packets across individual links, while packets are routed between networks.
Routing: The process of selecting paths for data to travel across interconnected networks. Routers inspect packet headers to choose the next network hop.
Payload (computing): The application or protocol data carried inside a larger data unit. The payload is the content that packet control fields deliver across the network.
Internet Protocol version 6: The sixth version of the Internet Protocol, using 128-bit addresses and a redesigned packet header. IPv6 provides a distinct packet format with a larger address space.
Network segment: A transport-layer data unit, especially a TCP unit containing header fields and application bytes. A TCP segment is encapsulated in an IP packet, so the terms name different layers.
Maximum transmission unit: The largest packet or frame size a network link can carry without fragmentation. This link limit determines whether an IP packet must be divided.
Transmission Control Protocol: A transport protocol that provides reliable, ordered byte-stream communication between applications. TCP data is carried inside IP packets, though TCP segments and packets are distinct units.

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