Wireless Network Watcher - scans your wireless network and displays the list of all computers and devices that are currently connected to your network.
NetBox - NetBox is an open source web application designed to help manage and document computer networks. NetBox was developed specifically to address the needs of network and infrastructure engineers.
Nmap - Nmap Free Security Scanner, Port Scanner, & Network Exploration Tool. Download open source software for Linux, Windows, UNIX, FreeBSD, etc.
phpIPAM - phpipam is an open-source web IP address management application (IPAM).
Angry IP Scanner - Open-source and cross-platform network scanner designed to be fast and simple to use
Infoblox DDI - Infoblox’s industry leading integrated, centrally managed approach to delivering enterprise-grade DNS, DHCP, and IP address management (DDI) supports current and evolving IT needs.