What is the effect of timeouts on retransmission in the EPD Pilot?

• A. Timeouts are used solely to measure latency and do not influence retransmission behavior.
• B. Timeouts trigger retransmission after no ACK/NAK, balancing latency and network congestion; overly short timeouts increase chatter, long timeouts reduce reliability.
• C. Timeouts cause immediate connection reset without retries.
• D. Timeout values determine how much encryption strength is used.

Answer: (B)

The key idea is that timeouts determine when a sender should retry after no confirmation is received. In the EPD Pilot, if an ACK or NAK doesn’t arrive within the allotted timeout, the sender treats the packet as lost and initiates a retransmission. This creates a balance between latency and network congestion: a short timeout leads to faster retries but can cause many unnecessary retransmissions and traffic if the network is just momentarily slow, increasing chatter. A long timeout reduces these unnecessary retries but delays recovery from actual losses, hurting reliability and throughput. Timeouts, therefore, actively govern retransmission behavior rather than just measuring latency, and they aren’t about resetting connections or changing encryption.