300-425 Question 81
Single answerA network engineer is configuring mDNS on a Cisco wireless network to support Apple AirPrint and AirPlay services. The network consists of multiple VLANs to segment user traffic. The engineer wants to ensure that mDNS advertisements from devices in one VLAN can be discovered by devices in other VLANs. Which feature should be configured to achieve this?
- A
Enable mDNS Gateway on the wireless controller
- B
Enable multicast routing on all Layer 3 switches
- C
Enable IGMP Snooping on all VLANs
- D
Enable FlexConnect Local Switching on the access points
Show answer and explanation
Correct answer: A
Explanation
The mDNS Gateway feature on a Cisco wireless controller is specifically designed to handle mDNS advertisements across VLANs, which is necessary for enabling service discovery (like AirPrint and AirPlay) in multi-VLAN environments. Without this feature, mDNS traffic would be restricted to the local VLAN, limiting the ability of devices in different VLANs to discover and use services.
- A. Correct.
Correct. The mDNS Gateway feature on the wireless controller allows mDNS advertisements to be forwarded across VLANs, enabling service discovery between devices in different VLANs.
- B. Incorrect.
Incorrect. While multicast routing is necessary for general multicast traffic, it does not handle mDNS advertisements across VLANs in a wireless environment. The mDNS Gateway feature specifically addresses this.
- C. Incorrect.
Incorrect. IGMP Snooping is used to optimize multicast traffic within the same VLAN, but it does not enable mDNS traffic to be forwarded between VLANs.
- D. Incorrect.
Incorrect. FlexConnect Local Switching is used for local traffic routing on access points, but it does not facilitate mDNS traffic across VLANs.