When should you consider enabling Request to send/clear to send (RTS/CTS) on a WLAN?

• A. When diagnosing network problems and when large frames experience high collision rates across a congested wireless network.
• B. When all traffic is small frames.
• C. Only during maintenance windows.
• D. Never; RTS/CTS has no benefit.

Answer: (A)

RTS/CTS acts as a medium-access guardrail on the wireless link. It introduces a quick handshake before a sender transmits, allowing the receiver to signal others to defer. This is most valuable in a crowded WLAN or when hidden nodes could cause collisions, because that reserve-and-deferr mechanism helps prevent multiple stations from transmitting at once.

Enabling RTS/CTS is especially helpful for large frames. The potential cost of a collision for a big payload is high, so the extra overhead of RTS/CTS is worth it because it dramatically reduces the chance of a costly collision and the need for retransmission. In contrast, for small frames the handshake overhead can outweigh the benefits, which is why RTS/CTS isn’t typically enabled unless you’re seeing problems.

So you’d consider turning it on when diagnosing network performance issues and you observe high collision rates with large frames in a congested wireless environment. It’s not about maintenance windows, and it’s not correct to say it has no benefit in general, since there are real scenarios where it improves performance.