TCP and UDP: Reliability Comparison

B.

TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) are both transport layer protocols that are used to transfer data over a network. However, they differ in the way they provide reliability for delivery of packets.

TCP is a connection-oriented protocol that establishes a reliable connection between two devices before transferring data. TCP guarantees the delivery of packets by using a variety of mechanisms such as error checking, message acknowledgement, and retransmission of lost packets. When a sender sends a packet, it waits for an acknowledgement from the receiver before sending the next packet. If a packet is lost or corrupted, the sender retransmits the packet. TCP also provides flow control to avoid overwhelming the receiver by sending too many packets at once. Flow control ensures that the sender sends packets at a rate that the receiver can handle, preventing packet loss due to congestion.

UDP, on the other hand, is a connectionless protocol that does not establish a reliable connection between two devices before transferring data. UDP provides a best-effort delivery service, which means that it sends packets to the receiver in a continuous stream without checking for errors or message acknowledgement. UDP does not provide any flow control mechanism, which means that it can overwhelm the receiver by sending too many packets at once. However, UDP is useful for applications that do not require reliable delivery of data, such as streaming video or audio.

In summary, TCP provides reliable delivery of data by establishing a connection between two devices and using mechanisms such as error checking, message acknowledgement, and retransmission of lost packets. TCP also provides flow control to avoid overwhelming the receiver. UDP, on the other hand, does not establish a reliable connection and provides best-effort delivery of data without error checking or flow control.