Which security service enables a network administrator to assign levels of service to a particular user?

Which security service enables a network administrator to assign levels of service to a particular user?

• A. CoS
• B. ACL
• C. Encryption
• D. AAA

Answer: (A)

Class of Service (CoS) lets you assign different levels of service to traffic from a user, so their packets can be prioritized, queued, or allocated bandwidth accordingly. By mapping a specific user’s traffic to a CoS class, network devices can treat that traffic with higher priority when the network is busy, ensuring better performance for that user’s applications. In wireless setups, this aligns with QoS mechanisms like 802.11e/WMM, which categorize traffic (for example, voice or video) so it gets faster access and lower latency.

Other options serve different security functions but don’t directly establish per-user service levels. Encryption protects data privacy, ACLs control who can access resources, and AAA handles authentication, authorization, and accounting, which may influence policy but does not by itself assign the actual service tier to a user’s traffic.