In a network monitoring system, a plug-in module specifies how devices of
that type should be discovered, including the directories or registries
that should be examined for device references, how these directories
should be examined, how the network should be probed for devices and how
detected devices should be identified. Each plug-in module has one of a
plurality of predetermined standard interfaces that allow the discovery
modules to operate with a single discovery framework. During a discovery
operation for a particular device type, the discovery framework
dynamically creates the discovery plug-in modules necessary to discover
devices of that type and controls these modules via the standard
interfaces to perform device type specific discovery.