Top picks: Trellix Intrusion Prevention System, Palo Alto Networks Advanced Threat Prevention, Snort Open Source — plus 39 more compared.
Network SecurityQuad9 is a free Intrusion Detection and Prevention Systems tool. Security professionals most commonly compare it with . All 42 alternatives are matched by shared capabilities, tags, and NIST CSF 2.0 coverage.
A closer look at the 8 most relevant alternatives and competitors to Quad9, including their key features and shared capabilities.
Next-gen IPS detecting & blocking network threats via signatures & behavior
IPS with inline AI models to block zero-day exploits and C2 attacks in real time
Snort is an open-source network intrusion detection and prevention system that analyzes traffic in real-time to identify and block malicious activity using rule-based detection methods.
Inline network detection and response system with IPS capabilities
SSL/TLS decryption appliance for inspecting encrypted network traffic
Network security solution for SMBs with behavioral intrusion detection
IDS integrated into RevealX NDR for real-time threat detection & investigation
BGP-based threat intelligence delivery for blocking malicious IPs at routers
Next-gen IPS detecting & blocking network threats via signatures & behavior
IPS with inline AI models to block zero-day exploits and C2 attacks in real time
Snort is an open-source network intrusion detection and prevention system that analyzes traffic in real-time to identify and block malicious activity using rule-based detection methods.
Inline network detection and response system with IPS capabilities
SSL/TLS decryption appliance for inspecting encrypted network traffic
Network security solution for SMBs with behavioral intrusion detection
IDS integrated into RevealX NDR for real-time threat detection & investigation
BGP-based threat intelligence delivery for blocking malicious IPs at routers
DNS-layer protection for devices across all network environments
5G network security platform for O-RAN/SD-RAN posture mgmt and threat detection.
Anomaly-based IDS using relative incongruity scoring to reduce false positives.
Hardware network security device for home/SMB with continuous threat updates.
Multi-layered Linux server security agent with WAF, malware scan, and IP filtering.
Hardware appliance for SSL/TLS inspection scaling via security service load balancing.
Real-time URL scanning tool that detects malicious links and bypasses evasion tactics.
24/7 network intrusion detection with immediate alert notifications.
Network security monitoring platform with IDS, PCAP capture, and asset discovery.
GIS-based visual analytics tool for wireless security risk assessment.
DNS-based cybersecurity platform for telcos, ISPs, enterprises & govts.
AI-driven RF monitoring platform for wireless device detection & threat mgmt.
Open-source Linux security agent with real-time dashboard: SSH, WAF, and CVE scanning
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.
Open source crowd-powered IDS/IPS and WAF for infra & app security.
A free, open-source network protocol analyzer for capturing and displaying packet-level data.
OSSEC is a versatile HIDS known for its powerful log analysis and intrusion detection capabilities.
Suricata offers real-time intrusion detection, intrusion prevention, and network monitoring.
SentryPeer is a fraud detection tool that monitors and detects fraudulent activities on SIP servers, capturing IP addresses and phone numbers of suspicious activities and providing a notification system to service providers.
Instructions for setting up SIREN, including downloading Linux dependencies, cloning the repository, setting up virtual environment, installing pip requirements, running SIREN, setting up Snort on Pi, and MySQL setup.
An open-source network security monitoring tool.
CrowdSec is a collaborative behavior detection engine that analyzes system logs to identify and block malicious activities using community-shared threat intelligence.
A wireless network detector, sniffer, and intrusion detection system
Sniffglue is a network sniffer tool written in Rust with advanced filter sensitivity options and secure packet processing.
An intrusion prevention system for SSH that blocks IP addresses after a set number of consecutive failed login attempts.
6Guard is an IPv6 attack detector sponsored by Google Summer of Code 2012 and supported by The Honeynet Project organization.
Snort 3 is the next generation Snort IPS with enhanced features and improved cross-platform support.
A multi-threaded intrusion detection system using Yara for network and stream IDS
DenyHosts is a script to block SSH server attacks by automatically preventing attackers after failed login attempts.
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.
Open source security-oriented language for describing protocols and applying security policies on captured traffic.
SSHGuard protects hosts from brute-force attacks by monitoring system logs, detecting attacks, and blocking attackers using a firewall.
BPF+ is a generalized packet filter framework that achieves both high-level expressiveness and good performance for network monitoring and intrusion detection applications.
BotScout.com provides proactive bot detection, screening, and banning through a powerful API.
Common questions security professionals ask when evaluating alternatives and competitors to Quad9.
The most popular alternatives to Quad9 include Trellix Intrusion Prevention System, Palo Alto Networks Advanced Threat Prevention, Snort Open Source, Trend Micro TippingPoint Threat Protection System, and Array ASI SSL Intercept. These Intrusion Detection and Prevention Systems tools offer similar capabilities and are frequently compared by security professionals evaluating their options.
