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Corporate Wargames: Red Teams vs Blue Teams

#cybersecurity #security #infosec #beginners

If you are new to the world of cybersecurity, you have probably heard people talking about "Red Teams" and "Blue Teams." When I first heard these terms, I honestly pictured a massive game of Halo or Team Fortress 2. And surprisingly, that mental image is not actually that far off.

The best way to see if your fortress is secure is to try and storm the gates. That is the core idea behind these two teams. So today, I am going to break down exactly who these teams are, what they do, and why they are so important for keeping our data safe.

Part 1: The Red Team (The Attackers)

Think of the Red Team as the "bad guys," but the kind you actually want on your payroll. These are the ethical hackers. Their whole job is to act like a real-world attacker and try to break into the organization.

A normal penetration tester might just look for bugs in one specific app. But a Red Team? They go big. They run full simulations that test everything. They utilize social engineering, try to sneak into physical office buildings, and write custom malware to get past defenses.

Their goal is simple. They want to see how far they can get once they slip inside the walls.

Tech Spotlight: Reconnaissance
Before they launch an attack, a Red Team needs to find an open door. They often write scripts to scan for these weak points. Here is a simple Node.js script someone might use to scan for open ports on a server:

const net = require('net');
const target = '192.168.1.10';
const scanPort = (port) => {
  const socket = new net.Socket();
  socket.setTimeout(2000);
  socket.on('connect', () => {
    console.log(`[+] Port ${port} is OPEN`);
    socket.destroy();
  });
  socket.on('timeout', () => {
    socket.destroy();
  });
  socket.on('error', (err) => {
    socket.destroy();
  });
  socket.connect(port, target);
};
// Scan common ports
[21, 22, 80, 443, 3389].forEach(scanPort);
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Part 2: The Blue Team (The Defenders)

If the Red Team is the spear, the Blue Team is the shield. These are the internal security staff who watch the organization's infrastructure day in and day out.

For a Blue Teamer, the job is all about vigilance. They analyze traffic logs, patch security bugs, and react to alarms. They are constantly looking for the subtle weirdness that indicates a Red Team (or a real criminal) is poking around. When they spot something, they jump into action to contain the threat and kick the intruder out.

Tech Spotlight: Detection
To catch that Red Team port scan we just talked about, a Blue Teamer might create a simple listener or "honeypot" to detect unauthorized access. Here is a Node.js script that acts as a trap. It listens on a sensitive port and logs an alert if anyone tries to connect:

const net = require('net');
const server = net.createServer((socket) => {
  const remoteAddress = socket.remoteAddress;
  console.log(`ALERT: Suspicious connection attempt from ${remoteAddress} on port 22!`);
  // Log this incident for further investigation
});
server.listen(22, () => {
   console.log('Honey port active. Watching for intruders...');
});
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Part 3: Purple Teaming (Working Together)

For a long time, these teams stayed in their own corners. Red Teams would attack and leave a report. Blue Teams would read it and scramble to fix things. It was competitive, and sometimes it caused friction.

That is where the Purple Team concept comes in. It is not always a separate team of people. It is more of a mindset where Red and Blue work side by side.

The Red Team launches an attack and tells the Blue Team immediately.
The Blue Team checks if their tools saw it.
If they missed it, the Red Team shows them exactly how to catch it next time.
This makes everyone better, faster.

Conclusion

The push and pull between Red and Blue teams is what drives modern cybersecurity. The Red Team exposes where you are weak, and the Blue Team builds the resilience you need to survive.

I hope this guide helped clarify the difference between these two critical roles. Whether you want to be the one breaking in or the one keeping them out, there is a place for you in this field. Good luck on your journey, and remember to aim to be at least 1% better today than you were yesterday!

Resources and Citations

  • CrowdStrike. (2025). Red Team vs. Blue Team: What’s the Difference? CrowdStrike
  • IBM. (2025). What is Red Teaming? IBM
  • NIST. (2025). Glossary: Red Team. National Institute of Standards and Technology. NIST Red Team
  • NIST. (2025). Glossary: Blue Team. National Institute of Standards and Technology. NIST Blue Team

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