The current setup already uses a strong authentication method (EAP-TLS with user certificates). The primary security weakness is the lack of network segmentation, as all users are placed in the same VLAN. To enhance security, you should implement role-based access control. By integrating with an external identity provider like Active Directory (AD) and using WxLAN policies, you can dynamically assign users to different VLANs and apply specific firewall rules based on their AD group membership. This segments the network and enforces the principle of least privilege.

A. Configure MAC Authentication Bypass (MAB): MAB is significantly less secure than 802.1X EAP-TLS and would be a security downgrade.

B. Configure user authentication using EAP-TTLS: While EAP-TTLS is a valid method, the organization already has a certificate infrastructure for EAP-TLS, which is generally considered more secure. The key improvement is role-based assignment, not changing the EAP type.

C. Configure host (machine) authentication: This authenticates the device, not the user. The requirement is to secure user access, and this option shifts the authentication focus away from the user.

1. Juniper Mist Documentation, "Access Assurance," Section: "Auth Policies." This section explains how to create authentication policies that can reference external identity providers like AD to assign roles.

2. Juniper Mist Documentation, "WxLAN Policies." This documentation describes how WxLAN policies (or roles) can be used to assign users to specific VLANs, apply firewall rules, and define other network access attributes based on the authentication result.

3. Juniper Mist Documentation, "Identity Provider." This section details the integration of Mist with identity providers like Active Directory for the purpose of role-based access control.