350-401 Question 306
Single answerA company is configuring network access control to secure its wired and wireless network. They want to use 802.1X authentication for corporate devices, MAC Authentication Bypass (MAB) for devices that do not support 802.1X, and Web Authentication (WebAuth) for guest users. During testing, they notice that devices unable to authenticate via 802.1X or MAB are not redirected to the WebAuth portal. What is the most likely cause of this issue?
- A
The VLAN for unauthenticated devices is not configured to redirect traffic to the WebAuth portal.
- B
The RADIUS server is not configured to support WebAuth.
- C
MAB is not enabled on the switch for devices that fail 802.1X authentication.
- D
802.1X authentication is configured incorrectly on the switch ports.
Show answer and explanation
Correct answer: A
Explanation
When implementing a combination of 802.1X, MAB, and WebAuth for network access control, it is important to ensure that unauthenticated devices (such as guest users) are placed in a VLAN or interface that redirects HTTP traffic to the WebAuth portal. Without this redirection, users will not see the authentication page, and WebAuth will fail to operate as intended. This configuration is critical for enabling guest access through WebAuth.
- A. Correct.
This is the correct answer. For devices to be redirected to the WebAuth portal, the unauthenticated VLAN or interface must be configured to send HTTP traffic to the portal. Without this, WebAuth cannot function.
- B. Incorrect.
While RADIUS is involved in 802.1X and MAB, WebAuth does not require RADIUS for basic redirection functionality. This is not the root cause of the issue.
- C. Incorrect.
MAB is already functioning for devices that do not support 802.1X, but this does not impact WebAuth redirection for guests. This option is incorrect.
- D. Incorrect.
If 802.1X authentication were misconfigured, corporate devices would fail to authenticate. However, this does not explain why devices are not redirected to the WebAuth portal. This option is incorrect.