UDP (User Datagram Protocol) resides at the Transport Layer, also known as Layer 4 in the OSI model.
Understanding the Transport Layer
The transport layer is crucial for managing communication between applications. As stated in our reference, this layer primarily consists of two protocols:
- Transmission Control Protocol (TCP)
- User Datagram Protocol (UDP)
UDP's Role at Layer 4
UDP is a connectionless protocol that offers a fast but unreliable method of data transmission. This contrasts with TCP, which is connection-oriented and provides reliable, ordered delivery of data.
Table Summarizing Layer 4 Protocols
| Protocol | Layer | Characteristics | Reliability | Use Cases |
|---|---|---|---|---|
| TCP | Layer 4 | Connection-oriented, reliable | High | Web browsing, email, file transfer |
| UDP | Layer 4 | Connectionless, unreliable | Low | Streaming, online gaming, DNS lookups |
Practical Insights
- Speed vs. Reliability: UDP is chosen when speed is more important than guaranteed delivery.
- Real-time Applications: Applications like online gaming and video streaming often use UDP because occasional packet loss is acceptable in exchange for lower latency.
