The network sensor is installed in the user's network and collects the information and transmits it to the policy server. Depending on your network configuration, you may need to install one or more network sensors on your network.
You can install Network Sensor on a physical machine or virtual machine.
Even if you choose Cloud-managed services, network sensors must be installed on your network.
For more information about sizing, See Software and Hardware Sizing.
The installation process is the same as installing the policy server. However, you must select 2. Network Sensor in step 2 of the installation.