UDP

User Datagram Protocol (UDP) is a core communication protocol in the internet protocol suite used to send data between devices with low overhead. Unlike TCP (Transmission Control Protocol), UDP is connectionless and does not guarantee packet delivery, order, or error correction. Its simplicity makes it faster and more efficient for real-time applications where speed is more important than reliability.
UDP is commonly used for video streaming, online gaming, VoIP calls, and other services where slight data loss is acceptable but low latency is essential.
Advanced
UDP operates at the transport layer of the OSI and TCP/IP models. It sends data in discrete units called datagrams without establishing a prior connection, reducing delays. Each datagram includes only minimal header information: source and destination ports, length, and checksum.
Advanced use cases integrate UDP with additional protocols for reliability, such as QUIC, which adds encryption and error handling. UDP’s lightweight nature also supports DNS queries, broadcasting, and multicasting, making it integral to internet functionality. Unlike TCP, UDP does not use congestion control, so developers must implement safeguards at the application layer if needed.
Relevance
Applications
Metrics
Issues
Example
An online multiplayer game uses UDP to send player position updates. Even if some packets are lost, the game continues smoothly because speed is prioritized over perfect accuracy. This allows real-time gameplay without noticeable lag.