Best Quad9 alternatives & competitors

libnids

libnids on SecurityListing: Libnids is an implementation of an E-component of Network Intrusion Detection System that emulates the IP stack of Linux 2.0.x and offers IP defragmentation, TCP stream assembly, and TCP port scan detection.

DenyHosts

DenyHosts on SecurityListing: DenyHosts is a script to block SSH server attacks by automatically preventing attackers after failed login attempts.

OSSEC

OSSEC on SecurityListing: OSSEC is a versatile HIDS known for its powerful log analysis and intrusion detection capabilities.

Fail2ban

Fail2ban on SecurityListing: Fail2ban is a daemon that automatically bans IP addresses showing malicious behavior by monitoring log files and updating firewall rules to prevent brute-force attacks.

BotScout.com

BotScout.com on SecurityListing: BotScout.com provides proactive bot detection, screening, and banning through a powerful API.

Suricata

Suricata on SecurityListing: Suricata offers real-time intrusion detection, intrusion prevention, and network monitoring.

BPF+: Exploiting Global Data-flow Optimization in a Generalized Packet Filter Architecture

BPF+: Exploiting Global Data-flow Optimization in a Generalized Packet Filter Architecture on SecurityListing: BPF+ is a generalized packet filter framework that achieves both high-level expressiveness and good performance for network monitoring and intrusion detection applications.

Trellix Intrusion Prevention System

Trellix Intrusion Prevention System on SecurityListing: A next-generation intrusion prevention system that combines signature-based and behavioral detection techniques to identify and block sophisticated network threats across hybrid environments.

wireshark

wireshark on SecurityListing: A free, open-source network protocol analyzer for capturing and displaying packet-level data.