Infiltrator Network Security Scanner 

Infiltrator is an intuitive network security scanner that can quickly audit computers for vulnerabilities, security holes and exploits, and information enumerations. Infiltrator can reveal security holes and alert the user.
infiltrator network auditing security network auditing

SecureCentral ScanFi Free Edition 

ScanFi is a web-based vulnerability assessment scanner for detecting and assessing network vulnerabilities across heterogeneous networks. ScanFi discovers, scans, reports, and supports vulnerability remediation.
network vulnerability assessment vulnerability scanner vulnerability assessment scanner network vulnerabilities sans top 20 asset discovery asset scan non-intrusive scan schedule scans missing patches vulnerability reports cve vulnerability remediation

NetInfo 

NetInfo is a collection of 15 different state-of-the-art network tools on a single, easy-to-use interface.
network utilities network tools ping traceroute lookup finger whois