300-425 Question 49
Select 4A network administrator is tasked with implementing QoS in a Cisco Enterprise Wireless Network to ensure voice traffic is prioritized across both the wired and wireless segments of the network. Which configuration steps should the administrator take to meet this requirement?
- A
Map the appropriate DSCP values from the wired network to the corresponding Wi-Fi Multimedia (WMM) Access Categories (AC).
- B
Enable QoS on the wireless LAN controller (WLC) and ensure SSID policies are set to voice priority.
- C
Use Layer 3 QoS policies exclusively; Layer 2 QoS is not required for wireless networks.
- D
Configure the APs to trust DSCP markings received from upstream wired devices.
- E
Ensure that the wired switches are configured with strict-priority queuing for voice traffic.
Show answer and explanation
Correct answers: A, B, D, E
Explanation
To implement QoS across a Cisco Enterprise Wireless Network, DSCP values must be mapped to WMM Access Categories to translate wired QoS markings into wireless priorities. QoS must be enabled on the WLC, and SSIDs should be configured to prioritize voice traffic. Additionally, APs must trust DSCP markings to maintain end-to-end QoS integrity, and wired switches should be configured with strict-priority queuing to prioritize voice traffic within the wired domain. Layer 2 QoS (WMM) is essential in wireless networks, so relying exclusively on Layer 3 QoS is incorrect.
- A. Correct.
Mapping DSCP values from the wired network to WMM Access Categories ensures proper QoS translation and prioritization across the wired and wireless segments.
- B. Correct.
Enabling QoS on the WLC and setting SSID policies to prioritize voice ensures that traffic classification is enforced on the wireless network.
- C. Incorrect.
This is incorrect because Layer 2 QoS (WMM) is required in wireless networks to ensure traffic prioritization within the Wi-Fi environment.
- D. Correct.
Configuring the APs to trust DSCP markings from wired devices ensures that QoS policies are maintained end-to-end from wired to wireless.
- E. Correct.
Strict-priority queuing on wired switches ensures that voice traffic is prioritized within the wired network, complementing wireless QoS policies.