Last Attempt HPE6-A78 Questions

For a company that wants to deploy an open WLAN for guests with the ease of access and encryption for capable devices, using a captive portal with Opportunistic Wireless Encryption (OWE) in transition mode would be suitable. The captive portal allows for a user-friendly login page for authentication without a pre-shared key, and OWE provides encryption to protect user data without the complexities of traditional WPA or WPA2 encryption, which is ideal for guest networks. Transition mode allows devices that support OWE to use it while still allowing older or unsupported devices to connect.

To prevent users from exploiting Address Resolution Protocol (ARP) on a network with ArubaOS-Switches, the correct approach would be to enable DHCP snooping globally and on VLAN 201 before enabling ARP protection, as stated in option C. DHCP snooping acts as a foundation by tracking and securing the association of IP addresses to MAC addresses. This allows ARP protection to function effectively by ensuring that only valid ARP requests and responses are processed, thus preventing ARP spoofing attacks. Trusting ports that connect to employee devices directly could lead to bypassing ARP protection if those devices are compromised.

The company’s goal is to prevent internal users from exploiting ARP within their ArubaOS-Switch network. Let’s break down the options:

Option A (Incorrect): Enabling ARP protection globally on Switch-1 and all VLANs is not the best approach. ARP protection should be selectively applied where needed, not globally. It’s also not clear why Switch-1 is mentioned when the exhibit focuses on Switch-2.

Option B (Incorrect): Making ports connected to employee devices trusted for ARP protection is a good practice, but it’s not sufficient by itself. Trusted ports allow ARP traffic, but we need an additional layer of security.

Option C (Correct): This is the recommended approach. Here’s why:

DHCP Snooping: First, enable DHCP snooping globally. DHCP snooping helps validate DHCP messages and builds an IP-MAC binding table. This table is crucial for ARP protection to function effectively.

VLAN 201: Enable DHCP snooping specifically on VLAN 201 (as shown in the exhibit). This ensures that DHCP messages within this VLAN are validated.

ARP Protection: Once DHCP snooping is in place, enable ARP protection. ARP requests/replies from untrusted ports with invalid IP-to-MAC bindings will be dropped. This prevents internal users from exploiting ARP for attacks like man-in-the-middle.

Option D (Incorrect): While static ARP bindings can enhance security, they are cumbersome to manage and don’t dynamically adapt to changes in the network.

In an AOS-8 mobility architecture, the Mobility Controller (MC) manages user roles and policies for wireless clients connecting to SSIDs. When a user connects to an SSID with WPA3-Enterprise security, the MC uses 802.1X authentication to validate the user against an authentication server, in this case, HPE Aruba Networking ClearPass Policy Manager (CPPM). The SSID is configured with specific roles:

Initial role: Applied before authentication begins (not specified in the question, but typically used for pre-authentication access).

Logon role: Applied during the authentication process to allow access to authentication services (e.g., DNS, DHCP, or RADIUS traffic).

802.1X default role (guest): Applied if 802.1X authentication fails or if no specific role is assigned by the RADIUS server after successful authentication.

In this scenario, the user successfully authenticates, and CPPM sends an Access-Accept message with an Aruba-User-Role Vendor-Specific Attribute (VSA) set to "contractor." The "contractor" role exists on the MC, meaning it is a predefined role in the MC’s configuration.

When the MC receives the Aruba-User-Role VSA, it applies the specified role ("contractor") to the user session, overriding the default 802.1X role ("guest"). The MC does not combine the contractor role with other roles like logon or guest; it applies only the role specified by the RADIUS server (CPPM) in the Aruba-User-Role VSA. This is the standard behavior in AOS-8 for role assignment after successful authentication when a VSA specifies a role.

Option A, "Applies the rules in the logon role, then guest role, and the contractor role," is incorrect because the MC does not apply multiple roles in sequence. The logon role is used only during authentication, and the guest role (default 802.1X role) is overridden by the contractor role specified in the VSA.

Option C, "Applies the rules in the contractor role and the logon role," is incorrect because the logon role is no longer applied once authentication is complete; only the contractor role is applied.

Option D, "Applies the rules in the contractor role and guest role," is incorrect because the guest role (default 802.1X role) is not applied when a specific role is assigned via the Aruba-User-Role VSA.

The HPE Aruba Networking AOS-8 8.11 User Guide states:

"When a user authenticates successfully via 802.1X, the Mobility Controller applies the role specified in the Aruba-User-Role VSA returned by the RADIUS server in the Access-Accept message. If the role specified in the VSA exists on the controller, it is applied to the user session, overriding any default 802.1X role configured for the WLAN. The controller does not combine the VSA-specified role with other roles, such as the initial, logon, or default roles." (Page 305, Role Assignment Section)

Additionally, the HPE Aruba Networking ClearPass Policy Manager 6.11 User Guide notes:

"ClearPass can send the Aruba-User-Role VSA in a RADIUS Access-Accept message to assign a specific role to the user on Aruba Mobility Controllers. The role specified in the VSA takes precedence over any default roles configured on the WLAN, ensuring that the user is placed in the intended role." (Page 289, RADIUS Enforcement Section)

ClearPass Onboard is part of the Aruba ClearPass suite and it provides a mechanism to deploy certificates to end-user devices, regardless of whether or not they are members of a Windows domain. ClearPass Onboard facilitates the configuration and provisioning of network settings and security, including the delivery and installation of certificates to ensure secure network access. This capability enables a bring-your-own-device (BYOD) environment where devices can be securely managed and provided with the necessary certificates for network authentication.