156-915.71 · Question #174
Which of these four Check Point QoS technologies prevents the transmission of redundant packets when multiple copies of a packet are concurrently queued on the same flow?
The correct answer is B. Retransmission Detection Early Drop (RDED). Check Point 156-915.71 Exam
Question
Which of these four Check Point QoS technologies prevents the transmission of redundant packets when multiple copies of a packet are concurrently queued on the same flow?
Options
- AWeighted Flow Random Early Drop (WFRED)
- BRetransmission Detection Early Drop (RDED)
- CIntelligent Queuing Engine
- DStateful Inspection
How the community answered
(38 responses)- A5% (2)
- B76% (29)
- C3% (1)
- D16% (6)
Explanation
Check Point 156-915.71 Exam
Topics
Community Discussion
4
Imani T.Jan 28, 2026RDED is the correct answer here. The whole point of Retransmission Detection Early Drop is that Check Point QoS can recognize when TCP retransmissions show up in the queue, meaning the original packet is still sitting there waiting, so it drops the duplicate before it wastes bandwidth. WFRED is about congestion management and probabilistically dropping packets before a queue fills up, which is a completely different problem it solves. Stateful Inspection is a firewall technology, not a QoS mechanism, and the Intelligent Queuing Engine is more of an overarching scheduling component rather than something specifically targeting duplicate packet detection.
Ingrid P.Feb 9, 2026Got RDED on my actual exam, almost talked myself into A before I remembered it targets duplicate packets specifically.
Imani T.Feb 11, 2026RDED tripping people up on that is so common because A sounds right until you remember deduplication is the specific job there, not just general reliability.
Bao N.Feb 4, 2026Stateful Inspection is obviously the trap here since that is a firewall mechanism and has nothing to do with QoS packet scheduling, so knock that one out immediately. The Intelligent Queuing Engine is real but it manages bandwidth allocation across rules, not deduplication of queued copies. WFRED is where a lot of people get stuck because it does involve early drop, but it works by probabilistically dropping packets before a queue fills up to avoid congestion collapse, not by identifying that the same packet is sitting in the queue twice. The answer that fits the specific scenario of multiple copies of the same packet already in the queue on the same flow is B, and the key word in the question is "redundant" combined with "concurrently queued." Here is what I am genuinely curious about: when RDED detects those duplicate copies, does it drop all but the first one received, or does it drop all but the most recently arrived copy? The direction matters if you think about out-of-order delivery and which copy is actually most likely to be valid at the endpoint.