Arkime vs Zeek vs Suricata: Self-Hosted Network Traffic Analysis & Packet Capture Guide 2026

Why Self-Host Your Network Traffic Analysis Platform?

Network traffic analysis is the foundation of security operations, incident response, and network troubleshooting. When a security event occurs, full packet capture (PCAP) and protocol-level metadata are the only sources of truth that cannot be altered or denied by attackers. Commercial solutions like Cisco Stealthwatch, Darktrace, and Corelight offer powerful capabilities — but at enterprise price tags that often exceed $50,000 per sensor.

Self-hosted open-source network traffic analysis tools give security teams complete visibility into their network without vendor lock-in, egress of sensitive traffic data to third-party clouds, or per-gigabyte licensing fees. For regulated industries handling PCI-DSS, HIPAA, or government workloads, keeping packet data on-premises is not optional — it’s a compliance requirement.

This guide compares three mature, actively maintained open-source platforms for network traffic analysis: Arkime (full packet capture and search), Zeek (protocol-level network analysis framework), and Suricata (high-performance IDS/IPS with NSM capabilities). Each serves a different primary use case, and together they form a powerful layered defense.

Project Overview

What Each Tool Does Best

Arkime — Full Packet Capture at Scale

Arkime (formerly Moloch) is designed for large-scale, full packet capture, indexing, and search. It stores raw PCAP data alongside session metadata in Elasticsearch, allowing analysts to search for specific flows and then download the exact packets for deep inspection. Arkime excels when you need to answer questions like “what exactly was transferred between these two IPs at 14:32?” — you search the session database, find the flow, and pull the PCAP.

Key strengths:

• Full packet retention — stores every byte of traffic for later forensic analysis
• Fast PCAP search — Elasticsearch-backed indexing enables sub-second session lookups
• Web UI included — no separate dashboard tool needed
• SPI (Session Protocol Independence) — parses 40+ protocols for metadata extraction
• Multi-node clustering — scales horizontally across capture nodes and Elasticsearch clusters

Zeek — Protocol-Level Network Intelligence

Zeek is a network analysis framework that transforms raw packet streams into high-level, protocol-aware log files. Unlike signature-based IDS tools, Zeek uses interpreters for individual protocols (HTTP, DNS, SSH, TLS, SMTP, etc.) to extract structured metadata. Zeek’s scripting language allows you to write custom detection logic, anomaly detection rules, and automated responses.

Key strengths:

• Protocol intelligence — understands 50+ network protocols at the application layer
• Scripting language — write custom detection, enrichment, and automation logic
• Structured logs — produces TSV/JSON logs for easy ingestion into SIEM systems
• Low false positives — behavior-based analysis, not signature matching
• Active community — strong academic and commercial support (Corelight)

Suricata — High-Performance Threat Detection

Suricata is a multi-threaded IDS/IPS engine capable of inspecting traffic at 10Gbps+ on commodity hardware. It uses a signature-based detection engine (compatible with Emerging Threats and Snort rules) combined with protocol analysis, file extraction, and Lua scripting for deep packet inspection. Suricata outputs alerts in EVE JSON format, making it easy to integrate with Elastic, Splunk, or any log aggregator.

Key strengths:

• Multi-threaded performance — scales across CPU cores for high-throughput inspection
• Signature + anomaly detection — combines rule-based and behavioral analysis
• File extraction — automatically extracts files from network streams for malware analysis
• IPS mode — can actively block malicious traffic inline
• Rule compatibility — supports Snort, Emerging Threats, and custom rule sets

Comparison Matrix

Docker Deployment

Arkime with Docker Compose

Arkime requires Elasticsearch/OpenSearch for its session database. Here is a production-ready deployment:

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services:
  elasticsearch:
    image: docker.elastic.co/elasticsearch/elasticsearch:8.13.0
    environment:
      - discovery.type=single-node
      - xpack.security.enabled=false
      - ES_JAVA_OPTS=-Xms1g -Xmx1g
    volumes:
      - es-data:/usr/share/elasticsearch/data
    networks:
      - arkime-net
    deploy:
      resources:
        limits:
          memory: 2g

  arkime:
    image: arkime/arkime:latest
    cap_add:
      - NET_RAW
      - NET_ADMIN
    network_mode: host
    environment:
      - ARKIME_ELASTICSEARCH=http://localhost:9200
      - ARKIME_PASSWORD_SECRET=change-this-to-random-string
      - ARKIME_INTERFACE=eth0
      - ARKIME_VIEWER_USER=admin
      - ARKIME_VIEWER_PASSWORD=secure-password-here
    volumes:
      - pcap-data:/data/pcap
      - ./config.ini:/opt/arkime/etc/config.ini:ro
    restart: unless-stopped

volumes:
  es-data:
  pcap-data:

The Arkime config.ini file controls capture parameters:

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[default]
elasticsearch=http://localhost:9200
passwordSecret=change-this-to-random-string
viewPort=8005
pcapDir=/data/pcap
pcapWriteMethod=mmap
maxPcapInQueue=20

Zeek with Docker Compose

Zeek runs as a standalone sensor, writing logs to a local or mounted directory:

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services:
  zeek:
    image: securityonion/zeek:latest
    cap_add:
      - NET_RAW
      - NET_ADMIN
    network_mode: host
    environment:
      - ZEEK_INTERFACE=eth0
      - ZEEK_LOG_DIR=/zeek/logs
      - ZEEK_NODE_TYPE=standalone
    volumes:
      - zeek-logs:/zeek/logs
      - ./node.cfg:/opt/zeek/etc/node.cfg:ro
      - ./local.zeek:/opt/zeek/share/zeek/site/local.zeek:ro
    restart: unless-stopped

volumes:
  zeek-logs:

Custom Zeek scripts go in local.zeek:

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@load base/frameworks/logging
@load base/protocols/http
@load base/protocols/dns

# Log all HTTP requests with full URI
redef HTTP::default_capture_password = T;

# Custom notice for suspicious DNS queries
event dns_request(c: connection, msg: dns_msg, query: string, qtype: count, qclass: count)
    {
    if ( /malware\.example\.com/ in query )
        {
        NOTICE([$note=DNS_SuspiciousQuery, $conn=c, $msg=fmt("Suspicious DNS: %s", query)]);
        }
    }

Suricata with Docker Compose

Suricata requires promiscuous mode and outputs alerts in EVE JSON format:

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services:
  suricata:
    image: jasonish/suricata:latest
    cap_add:
      - NET_ADMIN
      - NET_RAW
    network_mode: host
    environment:
      - SURICATA_OPTIONS=-i eth0
    volumes:
      - suricata-log:/var/log/suricata
      - suricata-rules:/etc/suricata/rules
      - ./suricata.yaml:/etc/suricata/suricata.yaml:ro
    restart: unless-stopped

volumes:
  suricata-log:
  suricata-rules:

Key suricata.yaml settings:

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vars:
  address-groups:
    HOME_NET: "[192.168.0.0/16,10.0.0.0/8]"
    EXTERNAL_NET: "!$HOME_NET"

outputs:
  - eve-log:
      enabled: yes
      filetype: regular
      filename: /var/log/suricata/eve.json
      types:
        - alert:
            payload: yes
            payload-printable: yes
        - http:
            extended: yes
        - dns:
            query: yes
            answer: yes
        - tls:
            extended: yes

Choosing the Right Tool

When to Combine Tools

Most mature security operations centers run multiple tools simultaneously:

• Zeek + Suricata: Zeek provides protocol-level intelligence (what happened), while Suricata provides threat detection (was it malicious). Zeek’s logs feed the SIEM for trend analysis; Suricata’s EVE alerts trigger immediate response actions.
• Arkime + Suricata: Suricata detects the threat and generates an alert; Arkime provides the PCAP for forensic verification. Analysts click an alert in their SIEM, then pivot to Arkime to see the exact packets.
• All three: Zeek for baseline traffic understanding, Suricata for real-time alerting, Arkime for forensic deep-dive. This is the “gold standard” NSM (Network Security Monitoring) stack.

Why Self-Host Your Network Monitoring Stack?

Commercial network security monitoring platforms charge per-sensor licensing fees that scale with network size. A 10-sensor deployment of a commercial NSM platform can cost $200,000+ annually in licensing alone. Self-hosted open-source tools eliminate these recurring costs while providing equivalent — and in some cases superior — capabilities.

Self-hosting also means your raw packet data, protocol logs, and alert records never leave your infrastructure. For organizations in regulated sectors, this is a hard requirement. Third-party cloud-based NDR (Network Detection and Response) platforms require traffic mirroring to external endpoints, creating both compliance risk and data exposure.

For network visibility, see our network simulation guide and WAF comparison. For broader security monitoring, our IDS/IPS guide covers Snort alongside these tools from a detection-focused perspective.

FAQ

What is the difference between Arkime, Zeek, and Suricata?

Arkime captures and stores full packet data (PCAP) for later forensic search and analysis. Zeek analyzes network traffic in real-time and produces structured protocol logs (HTTP, DNS, TLS, etc.) for behavioral analysis. Suricata inspects traffic against threat signatures to detect and potentially block malicious activity. They serve complementary roles: Arkime for forensics, Zeek for intelligence, and Suricata for detection.

Can these tools run on the same server?

Yes, all three can run simultaneously on a single server using port mirroring (SPAN) or a network TAP. However, resource requirements should be considered: Arkime needs significant storage for PCAP data (hundreds of GB to TB), Zeek needs CPU for protocol parsing, and Suricata needs CPU for multi-threaded signature matching. A dedicated sensor with 16+ cores, 64GB RAM, and 2TB+ SSD storage can run all three comfortably on a 1Gbps link.

How much storage does Arkime require?

Storage depends on traffic volume and retention policy. As a rough estimate, a 1Gbps link generates approximately 10TB of PCAP data per day at full capture. Most organizations use Arkime with 7-30 day retention, requiring 70-300TB of storage. You can reduce storage by filtering traffic (capturing only specific subnets), using compression, or storing only session metadata while keeping PCAP for flagged sessions only.

Does Zeek replace a SIEM?

No. Zeek produces structured log files that need to be stored, searched, and correlated. A SIEM (like Elastic Security, Wazuh, or Security Onion) ingests Zeek logs alongside other data sources for correlation, alerting, and dashboards. Zeek is a data source — the SIEM is the analysis platform.

Can Suricata operate as an IPS (inline blocking)?

Yes. When deployed inline (between the network and the protected segment), Suricata can drop malicious packets using the drop action in rules. This requires careful rule tuning to avoid false positive blocks. Most organizations start in IDS mode (alert-only), validate rule accuracy over several weeks, then selectively enable IPS mode for high-confidence rules.

Do these tools support encrypted traffic inspection?

Suricata can inspect TLS handshakes and extract certificate metadata (SNI, issuer, validity) but cannot decrypt TLS-encrypted payload data without the server’s private key. Zeek similarly extracts TLS metadata. Arkime captures the encrypted packets but cannot decrypt them. For full encrypted traffic inspection, you need TLS termination at a proxy (like a WAF) and then inspect the decrypted traffic.