Network-based IDS (NIDS) vs host-based IDS (HIDS)

Both Suricata and Wazuh can function as Intrusion Detection Systems (IDS), but they operate in different ways, and only Wazuh is primarily considered a Host-Based Intrusion Detection System (HIDS). Here's why:

1. Wazuh - A Host-Based IDS (HIDS)

• Primary Role: Wazuh is primarily a HIDS because it installs an agent on each monitored host to collect security-related data.

• Key Features:

  • Log analysis (syslog, auth logs, application logs)

  • File Integrity Monitoring (FIM) (detects changes to critical files)

  • Rootkit & malware detection

  • Policy & compliance monitoring (e.g., CIS benchmarks)

  • Behavioral analysis (anomaly detection)

• Why HIDS? Wazuh operates at the host level, analyzing activities on the endpoint itself (like file changes, user logins, and process anomalies), making it a true HIDS.

2. Suricata - Primarily a Network-Based IDS (NIDS)

• Primary Role: Suricata is primarily a NIDS/NIPS (Network Intrusion Detection/Prevention System) that inspects network traffic for malicious activity.

• Key Features:

  • Deep packet inspection (DPI)

  • Signature-based detection (using rules like Snort/Suricata rules)

  • Protocol analysis (HTTP, DNS, TLS, etc.)

  • Anomaly-based detection (e.g., detecting DDoS, port scans)

• Why NIDS? Suricata does not run as an agent on hosts; instead, it monitors network traffic (e.g., at a firewall, gateway, or mirrored port). While it can analyze traffic to/from a host, it does not monitor host-level activities like file changes or process behavior.

Here’s a tabulated comparison of Suricata and Wazuh in the context of Host-Based Intrusion Detection (HIDS) and Network-Based Intrusion Detection (NIDS):

Feature	Wazuh (HIDS)	Suricata (NIDS/NIPS)
Primary Role	Host-Based IDS (HIDS)	Network-Based IDS/IPS (NIDS/NIPS)
Deployment	Agent-based (installed on hosts)	Network-level (monitors traffic flows)
Key Functions	- File Integrity Monitoring (FIM) - Log analysis - Rootkit/malware detection - Compliance checks (CIS, PCI-DSS) - Behavioral anomaly detection	- Deep Packet Inspection (DPI) - Signature-based detection (Snort-compatible rules) - Protocol analysis (HTTP, DNS, TLS) - Detection of scans/DDoS attacks
Host-Level Monitoring?	Yes (tracks file changes, processes, user logins)	No (only inspects network packets, even in host-based mode)
Network Traffic Analysis?	Limited (can analyze forwarded logs)	Yes (real-time traffic inspection)
Best For	Endpoint security, compliance, host-based threats	Network security, detecting malicious traffic patterns
Common Use Case	- Server/workstation monitoring - Detecting unauthorized file changes - SIEM integration (Elastic Stack)	- Firewall/IPS complement - Detecting exploits, C2 traffic, scans - Network traffic logging

When to Use Each?

Scenario	Recommended Tool
Monitoring host file changes, user logins, or process anomalies	Wazuh (HIDS)
Inspecting network traffic for malware, exploits, or attacks	Suricata (NIDS)
Needing both host and network security	Wazuh + Suricata (Integrated)

If you need host-based intrusion detection, Wazuh is the better choice. If you need network-level threat detection, Suricata is more suitable. Many security setups use both for layered defense (Wazuh for hosts, Suricata for network).