Qualys - Qualys helps your business automate the full spectrum of auditing, compliance and protection of your IT systems and web applications.

McAfee Network Security Platform - McAfee Network Security Platform guards all your network-connected devices from zero-day and other attacks, with a cost-effective network intrusion prevention system.

Nessus - Nessus Professional is a security platform designed for businesses who want to protect the security of themselves, their clients, and their customers.

Suricata - Suricata is a high performance Network IDS, IPS and Network Security Monitoring engine.

AlienVault USM (from AT&T Cybersecurity) - AlienVault USM Anywhere delivers powerful threat detection, incident response, and compliance management for cloud, on-premises, and hybrid environments.

snort - Snort is a free and open source network intrusion prevention system.