CompTIA Network+ (N10-006) — Question 22

As part of unified communications services, QoS must be implemented. DSCP and CoS map to which of the following OSI layers? (Select TWO)

Answer options

• A. Layer 1
• B. Layer 2
• C. Layer 3
• D. Layer 4
• E. Layer 5

Correct answer: B, C

Explanation

The correct answers are B and C because CoS (Class of Service) operates at Layer 2 (Data Link Layer) and DSCP (Differentiated Services Code Point) functions at Layer 3 (Network Layer) of the OSI model. The other options (A, D, and E) do not pertain to the mapping of QoS mechanisms like DSCP and CoS.