TCP vs UDP: Differences and Use Cases

TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) are two fundamental transport layer protocols used in network communication. Both protocols are designed to facilitate the transfer of data between devices, but they differ in their approach and features.

TCP is a connection-oriented protocol, which means it establishes a reliable connection between two devices before transmitting data. This connection is established using a three-way handshake process, where devices exchange SYN, SYN-ACK, and ACK flags to establish a connection. TCP also uses a sequence number and acknowledgment system to ensure that data is transmitted and received correctly. If a packet is lost, TCP will retransmit the packet to ensure reliable communication. This process adds overhead to the protocol, making it suitable for applications where data integrity and reliability are crucial, such as email and web browsing.

UDP, on the other hand, is a connectionless protocol, which means it does not establish a connection before transmitting data. Instead, it sends data as a series of datagrams, which can be lost during transmission. UDP does not provide error detection or correction, nor does it perform flow or congestion control. This makes it a lightweight protocol, suitable for applications where speed is more important than reliability, such as real-time streaming and online gaming.

In summary, TCP is a reliable, connection-oriented protocol that guarantees delivery, while UDP is a fast, connectionless protocol that does not guarantee delivery and is best suited for applications where speed is more important than reliability.