Explanation
This is because an Endpoint Context Server (ECS) is a feature that allows ClearPass to receive contextual information from external sources, such as Aruba Central, and use it for policy enforcement and reporting. An ECS can be configured to point to the Aruba Central API and fetch data such as device type, category, OS, applications, traffic flows, etc.
An ECS can be used to communicate the information that an IoT client has used SSH to Aruba ClearPass Policy Manager (CPPM). The ECS can query the Aruba Central API and retrieve the network traffic flows of the wireless IoT devices that are categorized as "Raspberry Pi" clients. The ECS can then filter the traffic flows by the SSH protocol and send the relevant information to CPPM. CPPM can then use this information for policy decisions, such as allowing or denying SSH access, or triggering alerts or actions.
B: On CPPM enable Device Insight integration. This is not a valid step because Device Insight is a feature that allows ClearPass to discover, profile, and fingerprint devices on the network using deep packet inspection (DPI) and machine learning (ML). Device Insight does not communicate with Aruba Central or receive information from it. Moreover, Device Insight might not be able to detect SSH traffic on encrypted wireless IoT devices without decrypting it first.
C: On Central configure APs and gateways to use CPPM as the RADIUS accounting server. This is not a valid step because RADIUS accounting is a feature that allows network devices to send periodic updates about the status and activity of authenticated users or devices to a RADIUS server, such as CPPM. RADIUS accounting does not communicate with Aruba Central or receive information from it. Moreover, RADIUS accounting might not be able to capture SSH traffic on wireless IoT devices without inspecting it first.
D: On Central set up CPPM as a Webhook application. This is not a valid step because Webhook is a feature that allows Aruba Central to send notifications or events to external applications or services using HTTP requests. Webhook does not communicate with CPPM or send information to it. Moreover, Webhook might not be able to send SSH traffic information on wireless IoT devices without filtering it first.