The Assimilation Monitoring Project is a highly scalable discovery-driven monitoring system. It integrates continuous discovery of servers, services, service dependencies, switch connections, and lots of other things into the monitoring process. The discovery is "stealthy" and will never set off any network security alarms. Adding servers doesn't measurably increase monitoring load, and the system is expected to easily scale into the 100K server range. The discovery work is distributed among all the nanoprobes (agents), which run scripts that spit out JSON. The central system (CMA) stores these strings and runs optional plugins to create graph nodes.
Cling is a complete, clean, and very flexible Java implementation of the UPnP Device Architecture specification. Additional UPnP service modules and graphical tools are also part of this project. Cling helps you create, control, and monitor UPnP-compatible services on your local network. Cling can be used as an UPnP/DLNA library for Android application development.
Fing is a command line tool for network and service discovery. It provides you a complete view of any network in a very short time. Its smart discovery automatically detects the network type and uses the best technique to scan it. The best results are achieved on Ethernet networks (including Wireless ones), where Fing is able to detect all network hosts, firewalled ones included. The service discovery feature quickly detects active TCP services on a target host or network. Fing is based on Look@LAN.