Episode 64: TCP and UDP — The Transport Layer’s Two Engines
TCP and UDP are the backbone of transport-layer communication, and understanding how they differ is critical to troubleshooting and configuring network services. In this episode, we compare these two protocols in depth, beginning with TCP’s reliable, connection-oriented features such as sequencing, acknowledgments, and retransmissions. You’ll learn how TCP ensures that data arrives intact and in order, making it ideal for applications like file transfers, web browsing, and email. We explain how the three-way handshake works, what window sizes mean, and how congestion control affects performance.
In contrast, we explore how UDP offers a lightweight, connectionless method of communication that favors speed over reliability. Commonly used in streaming, DNS, and VoIP, UDP sends data without waiting for responses or retransmissions. We highlight the benefits and trade-offs of each protocol and explain how to determine which one is in use based on port numbers and application type. By the end of this episode, you'll not only be able to identify the differences between TCP and UDP but also explain why one is chosen over the other in different network scenarios.
