In networking, what is the primary difference between TCP and UDP?

In networking, what is the primary difference between TCP and UDP?

• A. TCP provides faster delivery with no error checking, while UDP ensures reliability.
• B. TCP uses connectionless delivery with no guaranteed ordering.
• C. TCP provides reliable, connection-oriented delivery with error checking and guaranteed ordering; UDP provides faster, connectionless, best-effort delivery with no guaranteed delivery.
• D. Both provide identical delivery guarantees.

Answer: (C)

The key idea is how each protocol handles reliability and connection state. TCP is reliable and connection-oriented: it establishes a connection, tracks the order of bytes, uses acknowledgments and retransmissions to ensure every piece arrives correctly and in sequence, and employs flow and congestion control to manage throughput. UDP, on the other hand, is connectionless and best-effort: it sends individual datagrams with no guarantee of delivery, no guarantee of order, and no built-in mechanism to recover lost packets, which makes it faster due to lower overhead. This contrast matches the description that TCP provides reliable, connection-oriented delivery with error checking and guaranteed ordering, while UDP provides faster, connectionless, best-effort delivery with no guaranteed delivery. The other statements either flip these characteristics or claim identical guarantees, which isn’t accurate.

The key idea is how each protocol handles reliability and connection state. TCP is reliable and connection-oriented: it establishes a connection, tracks the order of bytes, uses acknowledgments and retransmissions to ensure every piece arrives correctly and in sequence, and employs flow and congestion control to manage throughput. UDP, on the other hand, is connectionless and best-effort: it sends individual datagrams with no guarantee of delivery, no guarantee of order, and no built-in mechanism to recover lost packets, which makes it faster due to lower overhead. This contrast matches the description that TCP provides reliable, connection-oriented delivery with error checking and guaranteed ordering, while UDP provides faster, connectionless, best-effort delivery with no guaranteed delivery. The other statements either flip these characteristics or claim identical guarantees, which isn’t accurate.