The scenario requires that the clients in the ''medical-mobile'' role are denied access to the 10.1.12.0/22 subnet, which is a range of IP addresses from 10.1.12.0 to 10.1.15.255. However, the current configuration in rule 5 has a subnet mask of 255.255.240.0, which means that it matches any IP address from 10.1.0.0 to 10.1.15.255. This is too broad and would deny access to other subnets in the 10.1.0.0/16 range that should be permitted according to the scenario.Therefore, the subnet mask in rule 5 should be changed to 255.255.252.0, which would match only the IP addresses from 10.1.12.0 to 10.1.15.255 and deny access to them as required by the scenario.1

1: Configuring Firewall Policies - Aruba, section ''Firewall Policies''

To configure CPPM to collect information from Intune on demand during the authentication process, you need to use the Intune extension for ClearPass. This extension allows ClearPass to query Intune for device compliance and configuration information using the Intune API.To use this extension, you need to register an app in Azure AD and grant it the required permissions to access Intune1

The Intune extension uses the device ID as the key to query Intune for device information. The device ID is a unique identifier that is assigned by Intune to each enrolled device. The device ID can be obtained from the client certificate that is used for EAP-TLS authentication.Therefore, the certificates issued to clients must include the Intune ID in the subject name, so that ClearPass can extract it and use it to query Intune2

The certificates issued to clients do not need to be issued by a well-known, trusted CA, as long as ClearPass trusts the CA that issued them. The certificates do not need to include the client MAC address in the subject name, as this is not relevant for querying Intune. The certificates do not need to be issued by a ClearPass Onboard CA, as this is not a requirement for using the Intune extension.

1: ClearPass Extensions - Microsoft Intune Integration - Aruba, section ''Configuring Microsoft Extension in ClearPass''2: ClearPass Extensions - Microsoft Intune Integration - Aruba, section ''Configuring EAP-TLS Authentication''

MAC Authentication Bypass (MAB) is a technique that allows non-802.1X-capable devices to bypass the 802.1X authentication process and gain network access based on their MAC addresses. However, MAB has some security drawbacks, such as the possibility of MAC address spoofing or unauthorized devices being added to the network. Therefore, it is recommended to use a custom MAC-Auth authentication method that adds an additional layer of security to MAB.

A custom MAC-Auth authentication method is a method that uses a combination of the MAC address and another attribute, such as a username, password, or certificate, to authenticate the device. This way, the device needs to provide both the MAC address and the additional attribute to gain access, making it harder for an attacker to spoof or impersonate the device. A custom MAC-Auth authentication method can be created and configured in ClearPass Policy Manager (CPPM) by following the steps in the Customizing MAC Authentication - Aruba page.

A profile conflict occurs when ClearPass Policy Manager (CPPM) detects a change in the device category or OS family of an endpoint that has been previously profiled. This could indicate that someone has spoofed the MAC address of a legitimate device and is trying to gain unauthorized access to the network. For example, if an endpoint that was previously profiled as a Printer suddenly shows a new profile of Computer, this could be a sign of an attack. You can find more information about profile conflicts and how to resolve them in the ClearPass Policy Manager User Guide1. The other options are not necessarily signs of unauthorized access, as they could have other explanations. For example, multiple DHCP options under the fingerprints could indicate that the device has connected to different networks or subnets, an Unknown status could indicate that the device has not been authenticated yet, and a lack of hostname or a random hostname could indicate that the device has not been configured properly or has been reset to factory settings.

This is because a parameter is a variable that can be defined and modified by the user or the script, and can be used to customize the behavior and output of the NAE script. A parameter can be referred to by using the syntax self ^ramsfname], where ramsfname is the name of the parameter.

By defining a parameter for the value, the developer can make the NAE script more flexible and adaptable to different scenarios and switches. The parameter can be set to a default value, such as 10, but it can also be changed by the user or the script based on the network conditions and requirements. For example, the parameter can be adjusted dynamically based on the average or standard deviation of the number of rejects per hour, or based on the feedback from the user or other admins. This way, the NAE script can trigger an alert only when the number of rejects is truly unusual and not just arbitrary.

A) Checking one of the access switches' RADIUS statistics and adding 10 to the number listed for rejects. This is not a good recommendation because it does not account for the variability and diversity of the network environment and switches. The number of rejects listed for one switch might not be representative or relevant for another switch, as different switches might have different traffic patterns, client types, RADIUS configurations, etc. Moreover, adding 10 to the number of rejects is an arbitrary and fixed value that might not reflect the actual threshold for triggering an alert.

B) Defining a baseline and referring to it for the value. This is not a bad recommendation, but it is not as good as defining a parameter. A baseline is a reference point that represents the normal or expected state of a network metric or performance indicator. A baseline can be used to compare and contrast the current network situation and detect any anomalies or deviations. However, a baseline might not be easy or accurate to define, as it might require historical data, statistical analysis, or expert judgment. Moreover, a baseline might not be stable or constant, as it might change over time due to network growth, evolution, or optimization.

C) Using 10 (per hour) as a good starting point for the value. This is not a good recommendation because it is an arbitrary and fixed value that might not reflect the actual threshold for triggering an alert. Using 10 (per hour) as the value might result in false positives or false negatives, depending on the network conditions and switches. For example, if the normal number of rejects per hour is 5, then using 10 as the value might trigger an alert too frequently and unnecessarily. On the other hand, if the normal number of rejects per hour is 15, then using 10 as the value might miss some important alerts and risks.