Which statement best describes a reliable protocol?

Which statement best describes a reliable protocol?

• A. They guarantee delivery of data.
• B. They do not guarantee delivery.
• C. They require encryption for operation.
• D. They do not support end-to-end connections.

Answer: (A)

Reliability in protocols means the system provides mechanisms to ensure data reaches the destination, often with correct order and without errors, using techniques like acknowledgments, sequence numbers, and retransmission of lost data. Because of these delivery guarantees, the statement that best describes a reliable protocol is the one that says data delivery is guaranteed. Encryption is about privacy, not reliability, so requiring encryption isn’t what makes a protocol reliable. End-to-end connection support is about the scope of the connection; a reliable protocol can support end-to-end connections (as TCP does), but reliability itself isn’t defined by whether end-to-end is supported.

Reliability in protocols means the system provides mechanisms to ensure data reaches the destination, often with correct order and without errors, using techniques like acknowledgments, sequence numbers, and retransmission of lost data. Because of these delivery guarantees, the statement that best describes a reliable protocol is the one that says data delivery is guaranteed.

Encryption is about privacy, not reliability, so requiring encryption isn’t what makes a protocol reliable. End-to-end connection support is about the scope of the connection; a reliable protocol can support end-to-end connections (as TCP does), but reliability itself isn’t defined by whether end-to-end is supported.