UDP

Definitions

1. UDP, or User Datagram Protocol, is a connectionless transport protocol that sends packets (called datagrams) without establishing a connection or guaranteeing delivery. Unlike TCP, UDP does not perform handshakes, ordering, or retransmission, which makes it significantly faster and lower-overhead but unreliable in the traditional networking sense. Each datagram is independent, and the application is responsible for handling lost or out-of-order packets if necessary. UDP is ideal for use cases where speed matters more than perfect reliability: live video and audio streaming, online gaming, DNS lookups, VoIP calls, and IoT sensor data. It operates at Layer 4 of the OSI model alongside TCP and uses port numbers to direct traffic to the correct application. Modern protocols like QUIC (which underpins HTTP/3) build reliability features on top of UDP to combine its speed advantages with delivery guarantees. UDP's simplicity and low latency make it indispensable for real-time applications.

   In plain English: A fast way to send data over the internet that doesn't check if everything arrived, perfect for things like video calls where speed matters more than perfection.

   Example: "Game servers use UDP because a dropped packet is better than a laggy one — just send the next frame."

Related Terms

• HTTP
• Rendezvous
• TCP
• RPC
• FTP
• SMTP
• IMAP
• QUIC
• NAT Traversal
• OSI Model
• TCP/IP
• Latency vs Throughput
• MTU
• HTTP/2
• HTTP/3
• Anycast
• SNI
• Negotiation
• Pong
• Redis Pipeline
• Server Push
• Socket Pool