Quality of Service & Traffic Management Flashcards
7 cards from real ACA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Quality of Service & Traffic Management flashcards as text
What is the primary purpose of Quality of Service (QoS) in a network?
Answer: To prioritize certain types of traffic to ensure performance
QoS prioritizes certain traffic types (such as voice and video) to guarantee the performance levels they require, rather than increasing raw bandwidth.
Which QoS marking method operates at Layer 2 of the OSI model?
Answer: 802.1p CoS
802.1p CoS (Class of Service) uses a 3-bit field in the 802.1Q VLAN tag to mark traffic at Layer 2.
What does DSCP stand for in the context of QoS?
Answer: Differentiated Services Code Point
DSCP stands for Differentiated Services Code Point, a 6-bit field in the IP header used to classify and prioritize network traffic.
Which queuing mechanism gives absolute priority to delay-sensitive traffic, ensuring it is always dequeued first?
Answer: Strict Priority Queuing (PQ)
Strict Priority Queuing always services the highest-priority queue first before any other queue, guaranteeing minimal delay for sensitive traffic like VoIP.
What is the valid range of DSCP values that can be assigned to IP packets?
Answer: 0–63
DSCP uses a 6-bit field in the IP header's ToS byte, giving a range of 0 to 63.
Which QoS mechanism enforces a traffic rate limit by dropping packets that exceed the defined rate?
Answer: Traffic policing
Traffic policing drops or re-marks packets that exceed the configured rate limit, providing hard enforcement of the policy.
What does Wi-Fi Multimedia (WMM) bring to wireless networks?
Answer: QoS prioritization of voice, video, best-effort, and background traffic
WMM is a Wi-Fi Alliance certification that implements QoS by defining four access categories — voice, video, best effort, and background — to prioritize traffic over wireless links.