Qualys Network Passive Sensor Deployment Guide

The document is a deployment guide for the Qualys Network Passive Sensor, detailing various deployment strategies for different enterprise sizes and network topologies. It outlines the recommended placement of sensors to optimize asset visibility, suggesting that sensors be deployed closer to client access points rather than at the core of the network. The guide includes specific recommendations for small, medium, and large enterprises, emphasizing the importance of registering all sensors to a single Qualys account. Additionally, it discusses passive sensor deployment scenarios and port mirroring techniques, including Local SPAN, RSPAN, and ERSPAN, to ensure effective monitoring of network traffic. The guide also highlights the critical role of the Network Passive Sensor in industrial networks, where it captures vital device identity information and supports the detection of operational technology endpoints. Best practices for mirroring configurations and use case scenarios are also included to assist in effective deployment.