Network Device Discovery. Part 1: Active Discovery
Since its introduction in 1998, ntop(ng) has been a pure (well beside DNS address resolution if enabled) passive network monitoring tool. Recently we have complemented it with active device discovery in order to find out if there are silent devices in our network, and what services/OS our devices are featuring. In this article we will analyze how active discovery works, leaving to a future article the analysis of passive discovery. Active discovery can be started on demand from the menu or from the network preferences to enable periodic …