You need to monitor your network traffic. You have heard of Suricata, Snort, and Zeek. But which one should you use? And can you run more than one at the same time?

This is the question every security team faces when building their network monitoring stack.

Suricata and Snort are similar. They are both IDS/IPS tools that inspect packets in real time. Zeek is different. It is a network analysis framework that generates logs and metadata.

Let me walk you through each tool, what makes them different, and how to pick the right one for your environment.

Important Disclaimer

This article is intended for educational and defensive purposes only. The techniques described here are shared to help security professionals understand emerging threats so they can better protect their systems.

Do not use these techniques against systems you do not own or do not have explicit written permission to test. Unauthorized testing is illegal in most jurisdictions.

The author assumes no liability for any damages, legal consequences, or other outcomes resulting from the use or misuse of this information. Never perform security tests without getting appropriate authorization. Stay legal. Stay ethical. Stay responsible.

The Quick Summary

Let us start with a quick overview before we get into the weeds.

Here is the short version. Suricata and Snort both do intrusion detection. They look at traffic in real time and alert you when something looks bad. Zeek does something different. It logs everything and gives you detailed metadata to analyze later.

What Is Snort?

Snort is the old-timer here. It has been around since 1998. Martin Roesch created it, and it basically started the open-source IDS movement.

Snort works by comparing network traffic against a set of rules. Each rule describes a pattern to look for. If Snort finds a match, it fires an alert.

Key Features:

• Rule-based detection
• Protocol analysis
• Content matching
• Packet logging
• Preprocessor plugins

The Good:

• Rock-solid and stable
• Huge rule base (both free and paid)
• Well-documented
• Easy to set up

The Bad:

• Single-threaded (does not scale)
• Struggles with high-speed networks
• Drops packets when things get busy

When to Pick Snort:

• Smaller networks
• Legacy environments
• When you want something simple
• When you already have Snort infrastructure

What Is Suricata?

Suricata showed up in 2010 as the new kid on the block. It was built specifically to handle high-speed networks.

The big difference is threading. Suricata can use multiple CPU cores. It can even use your GPU for pattern matching. This makes it way faster than Snort on modern hardware.

Here is the best part. Suricata uses the same rules as Snort. You can literally take your Snort rules and use them with Suricata.

Key Features:

• Multi-threaded
• GPU acceleration
• Protocol detection
• TLS fingerprinting
• HTTP logging
• JSON output

The Good:

• Fast and scalable
• Compatible with Snort rules
• Actively developed
• TLS fingerprinting is a killer feature

The Bad:

• Configuration can be complex
• Needs more resources
• Newer, so less battle-tested than Snort

When to Pick Suricata:

• High-speed networks
• Cloud environments
• When performance matters
• When you need TLS fingerprinting

What Is Zeek?

Zeek is the odd one out. It is not really an IDS/IPS. It is a network analysis framework.

Zeek used to be called Bro. It was created in 1995 at Lawrence Berkeley National Lab. Unlike Snort and Suricata, Zeek does not alert on bad stuff in real time. Instead, it logs everything and lets you analyze it later.

Zeek parses network protocols and pulls out information. It logs HTTP requests, DNS queries, SSL certificates, and a ton of other stuff. The logs can either be fed to a SIEM or used for investigation purposes.

Key Features:

• Protocol parser
• Connection tracker
• Metadata extraction
• Scripting capabilities
• Detailed logging

The Good:

• Highly visible
• Rich metadata
• Scalable
• Good for research
• Good for hunting threats

The Bad:

• Not an IDS in the usual sense
• Lots of storage required
• Needs to be integrated with other tools for alerts

Why Choose Zeek?

• Security Research
• Digital Forensics
• Threat Hunting
• When you need to see everything
• When you have a SIEM that needs logs

The 5W and H Comparison

Practical Installation Examples

Installing Snort

# Ubuntu/Debian
sudo apt-get update
sudo apt-get install snort

# Configure Snort
sudo vi /etc/snort/snort.conf

# Run Snort in IDS mode
sudo snort -A console -q -c /etc/snort/snort.conf -i eth0

Installing Suricata

# Ubuntu/Debian
sudo apt-get update
sudo apt-get install suricata

# Configure Suricata
sudo vi /etc/suricata/suricata.yaml

# Run Suricata in IDS mode
sudo suricata -c /etc/suricata/suricata.yaml -i eth0

Installing Zeek

# Ubuntu/Debian
sudo apt-get update
sudo apt-get install zeek

# Configure Zeek
sudo vi /usr/local/zeek/etc/node.cfg

# Run Zeek
sudo zeekctl deploy

Practical Use Cases

Use Case 1: Small Office Network

The Setup: A small office with 50 employees. The network has a single internet connection.The budget is very low.

Recommendation: Snort

Why: Snort is easy to set up and maintain. It consumes few system resources. Rule set is ready for use.

Use Case 2: Large Enterprise Network

The Setup: A large enterprise with 5,000 employees. There are multiple internet connections in the network. There are several remote locations.

Recommendation: Suricata

Why: It can scale nicely on current hardware. It is capable of processing high-speed data without packet loss. It can be implemented as an IDS or IPS as well.

Use Case 3: Security Operations Center (SOC)

The Setup: Security Operations Center (SOC), which is keeping an eye on multiple networks where the team needs visibility.

Recommendation: Zeek

Why: Zeek generates logs and metadata files. These logs can be used for analysis and threat hunting by putting them into SIEM for correlation and alerting purposes.

Running Them Together

Here is the thing. You do not have to choose just one.

• You can run Suricata or Snort for real-time detection. And you can run Zeek alongside them for deep visibility.
• Many organizations do this. Suricata alerts on malicious traffic in real time. Zeek logs everything for later analysis. The logs feed into a SIEM. The SIEM correlates the alerts and logs.

This gives you the best of both worlds. Real-time detection and deep visibility.

Suricata vs Snort Performance

The biggest difference between Suricata and Snort is performance.

In practical terms, Suricata can handle 10 Gbps traffic on modern hardware. Snort struggles with anything over 1 Gbps.

If you have a high-speed network, Suricata is the better choice.

Zeek Logs vs Suricata Alerts

Another way to think about these tools is alerting versus logging.

Suricata generates alerts. It tells you when something suspicious happens. Zeek generates logs. It tells you everything that happens.

Suricata is for detection. Zeek is for visibility.

Suricata vs Snort: Rule Compatibility

Suricata is compatible with Snort rules. You can use the same rule files on both tools.

This is a huge advantage. You can develop rules on Snort and deploy them on Suricata. Or you can switch from Snort to Suricata without rewriting your rules.

But there are some differences. There are other Suricata features which are not available in Snort. These features can be utilized to create better rules.

Zeek Scripting

Zeek has a powerful scripting language. Scripts can be written to analyze protocols, extract data, and create alerts.

That is why Zeek is such an effective tool. There is no need to work with preset rules only. Custom analysis can be done according to your requirements.

For instance, a Zeek script can be written to detect SQL injection attacks. Another Zeek script can be written to detect weak ciphers used by SSL traffic.

Snort vs Zeek: Different Philosophies

Snort and Zeek have different philosophies.

• Snort is a detection tool. It looks for known patterns and alerts when it finds them. It is designed to catch attackers.
• Zeek is an analysis tool. It observes and records everything. It is designed to help you understand your network.
• Snort is like a security guard. Zeek is like a security camera.

Summary: Which One Should You Choose?

The Bottom Line

Here is the honest truth. All three are good tools. Each has its strengths and weaknesses.

The best choice depends on your specific needs. But you do not have to choose just one.

Run Suricata for real-time detection. Run Zeek for deep visibility. Feed the logs into a SIEM. This gives you the best of both worlds.

Start with one tool. Learn it well. Add others as your needs grow.

The important thing is to start monitoring your network. Any of these tools will help you do that.

FAQ Section

What is the difference between Suricata and Snort?

Suricata is multi-threaded and fast-paced, whereas Snort is single-threaded and is suitable for small setups. The other difference is that Suricata is GPU-enabled and can utilize Snort's rules.

What is Zeek used for?

Zeek is a framework used for analyzing network traffic with the purpose of gaining deeper visibility into it. It creates logs and metadata for later analysis.

Which IDS/IPS should I use?

The choice depends on your environment. Employ Snort for networks with little resources. Employ Suricata for high bandwidth networks. Deploy Zeek for in-depth analysis and research on security. Most companies deploy Suricata in real-time for detection with Zeek for logging.

Can I run Suricata and Zeek together?

Yes. It is a good practice to run both Suricata and Zeek. Suricata performs intrusion detection and alerting in real-time while Zeek delivers logs which may be analyzed for threat hunting and forensic investigation purposes.

Is Suricata faster than Snort?

Yes. Suricata is a multi-threaded tool that has GPU acceleration. Snort is a single-threaded tool. Suricata is capable of working at 10 Gbps with current hardware, whereas Snort cannot work with more than 1 Gbps.

Can I use Snort rules with Suricata?

Yes. Suricata is compatible with Snort rules. The same rules files can be used for both tools.