MxToolBox
Description: MxToolBox is a suite of network monitoring and troubleshooting tools for email, DNS, and other internet protocols. It offers over 30 tools to test, measure, and analyze infrastructure.
Type: software
Nmap
Description: Nmap is an open source network discovery and security auditing tool. It is used to discover hosts and services on a network and to detect potential vulnerabilities.
Type: software
Pricing: Free