What is Zero Trust Security - How the Model Works?

Zero trust security is like having a careful bouncer guard the door to your company’s digital world. No one gets access just because they seem trustworthy, whether in the office or remotely. Instead, every person and device must prove they are who they say they are before they can access anything important, like systems, apps, or sensitive data. Even then, they only see what’s necessary for their role, nothing more.
 

This tight security prevents cybercriminals from getting in. As a result, only the right people have access to the right things, keeping your digital space safe. Gartner predicts that by 2025, 60% of businesses will adopt this security. It’s becoming the new standard for online protection.

What is Zero Trust Security?

For years, businesses have used a "castle-and-moat" approach to cybersecurity. Think of it like a castle with a moat around it. If you’re outside, you're considered a threat. But, once you're inside, you're automatically trusted. That sounds good, right? However, here’s the problem: once someone’s inside, they can easily move around and cause major damage, like stealing data or hacking systems.
 

Zero-trust changes everything. Instead of focusing on who’s inside or outside the network, it checks who you are and what you can do. Whether at the office, working from home, or on the go, you only get access to what’s necessary for your job. This means no one can access more than they need, regardless of where they are.
 

Zero trust security doesn’t stop at a single check. Instead, it keeps verifying your identity every time you access something. For example, even if someone steals your password, they can’t wander around the network. That’s because each action is checked, ensuring everything stays secure.

Understanding the Zero Trust Model

In 2010, John Kindervag, a researcher at Forrester, introduced the zero-trust security model. The concept is simple: “Never trust, always verify.”
 

So, what does this mean? No one, whether inside or outside your network, gets access automatically. Every user and device must be verified each time before they can access anything. Even if someone has logged in before, they still need to prove their identity again. Trust is not assumed; it’s earned.
 

This zero trust strategy ensures that only the right people can access the right resources, and only when necessary. Whether it’s an employee at home or a contractor on the go, it keeps things secure. For years, businesses used the “castle-and-moat” model. The idea was simple: if you were inside the network (the “castle”), you were trusted. If you were outside (the “moat”), you were considered a threat.
 

However, with the rise of remote work and the cloud, this model no longer works. Employees now work from anywhere, from home, on the road, or at a café. As a result, the traditional perimeter isn’t enough to protect your network. Once a hacker breaks through the moat, they can move around freely, accessing sensitive information. For example, they could steal customer data or even launch a ransomware attack.

Why Zero Trust Security is Important?

Cybersecurity is a hot topic, and for good reason. With data breaches happening simultaneously and remote work becoming more common, businesses need stronger security measures. In the past, companies relied on firewalls to create a “safe zone” around their networks. If employees needed remote access, they’d use a VPN. However, this system has flaws. For instance, if someone steals a VPN login, like in the Colonial Pipeline breach, hackers can easily gain access.
 

A few years ago, most employees worked in the office, and only a few needed remote access. Now, things have changed. With more people working from home, businesses depend heavily on VPNs. Sadly, this creates more opportunities for hackers to steal login info.
 

Why Traditional Security No Longer Works?

Old security worked when everything was stored in one place, usually an on-site data center. But today, things are different. Data is spread across cloud services and private data centers, and as a result, the old "perimeter" model no longer works.

Zero-trust changes the game. Unlike traditional security, it doesn’t trust anything by default. Instead, it checks who you are, what device you’re using, and why you need access. So, even if hackers steal a login, they won’t get far.

Zero Trust Architecture

Imagine trying to enter a building, but a guard is at every door. No one gets in without proving they belong, whether a regular or a visitor. That’s the idea behind Zero Trust Architecture (ZTA). No one gets automatic access to your network, apps, or data. Everyone must prove they’re allowed in, every single time. In short, Zero Trust ensures that only the right people and devices have access, and only when necessary.

Key Technologies in Zero Trust Architecture

So, how does the zero trust security model work? It uses several key security tools:
 

• Identity and Access Management (IAM): It manages who can access what.
• Multi-Factor Authentication (MFA): Users prove their identity with a password and a second factor, like a phone code.
• Micro-Segmentation: The network splits into smaller parts, so access is more controlled.
• Encryption: Data scrambles, so only authorized users can read it.
• Real-Time Monitoring: It constantly watches for suspicious activity.
• These tools work together to ensure everything is verified before access is granted. No exceptions.

Zero Trust Use Cases

Here we will describe various use cases of zero trust security. 
 

1. Multicloud Security: Many businesses today use several cloud services. This is ideal for this setup because it limits access based on identity, no matter where the data is stored. In other words, zero trust acts as a guard, letting only verified users into the cloud. Even if your data moves across different clouds or infrastructure changes, zero trust ensures everything remains secure and protected.
    
2. Supply Chain Security: Companies often need to allow third parties, like vendors and contractors, to access their networks. But, this opens the door for hackers. They can compromise vendor accounts to break into your system. Zero trust security solves this by continuously verifying every user or system trying to access your network. Moreover, it grants only necessary access, so even if a hacker steals a vendor’s login, they can’t access your sensitive data.
    
3. Remote Access for Employees: Before, businesses relied on VPNs to connect remote workers. However, VPNs can’t scale easily and don’t stop hackers from moving inside the network once they’re in. As a result, Zero Trust uses Zero Trust Network Access (ZTNA), which checks who the employee is before granting access. Then, it gives access only to the tools and data the employee needs to do their job. This limits exposure and protects your network.
    
4. IoT Security: They are smart cameras and sensors, that are common in many businesses. But, they can be vulnerable to cyberattacks, as hackers often use them to spread malware. With zero trust, every IoT device constantly monitored. Before they connect to the network, they must prove they are secure. If a device shows any signs of compromised, it immediately blocks. This way, only trusted devices can access your network, keeping everything safe.

Why Zero Trust Architecture Matters?

Zero trust security doesn’t just protect one area of your network as it secures everything: users, apps, and infrastructure. This approach makes it much harder for hackers to break in.
 

1. User: The first step in Zero Trust is authentication. Before anyone can access your system, we check that they are who they claim to be. This requires to do with strong authentication, such as passwords and a verification code. Additionally, users only get access to what they need. If they try to log in from an untrusted device, it’s checked first.
    
2. Application: With Zero Trust, no app automatically trusts. If one app wants to communicate with another, they must prove they’re safe. This prevents hackers from using a compromised app to access sensitive data.
    
3. Infrastructure: It also secures your infrastructure, routers, cloud services, IoT devices, and more. Every part of your system is continuously monitored. This way, even if one part is breached, attackers cannot easily move around. They are blocked before causing damage.
    

Zero Trust vs VPN

Both zero Trust and VPNs secure network access, but they do so in different ways. Here’s how they compare.

Zero Trust follows the principle of "never trust, always verify." Every time you or anyone else tries to access something, Zero Trust checks your identity, device, and location. It only grants the minimum access needed. Imagine a security guard who asks for your ID every time you enter a building.
 

In contrast, a VPN (Virtual Private Network) creates a secure tunnel to the network. Once authenticated, you get wider access to everything inside. It's like getting a VIP pass, you can roam freely inside without being checked again.

Key Differences Between Zero Trust and VPN:

Access Control
 

• Zero Trust: Each access request is verified based on your identity, device, and location. It’s like showing your ID every time.
• VPN: Once you're logged in, you get wider access without further checks. Think of it like a stamp on your hand that lets you roam freely.

Security Philosophy
 

• Zero Trust: It assumes nothing is trusted unless verified. Every device, user, and action is constantly checked to prevent threats.
• VPN: Once you're in, you're trusted. There's no further verification, much like entering a room and not needing to show ID again.

Flexibility
 

• Zero Trust: It’s flexible and works across different environments, like cloud and hybrid networks. It’s ideal for today’s modern work setups.
• VPN: VPNs work well in simpler setups but can struggle with cloud networks and remote work, where things are constantly changing.

Implementation
 

• Zero Trust: Setting up Zero Trust can be a bigger project. It requires a security overhaul with various tools to ensure ongoing checks.
• VPN: VPNs are easier to set up. You can quickly create a secure connection, but it doesn’t provide the same as Zero Trust.

Our Learner Also Reads: Network Security vs Cybersecurity - Comparing Key Concepts

 

Conclusion

Zero Trust Security is a smart way to protect your company’s data. It never assumes anyone is trustworthy, whether they’re inside or outside your network. Instead, it checks every access request to ensure the right permissions are in place. This approach assumes that both insiders and outsiders can be threats. So, it limits access based on who you are, what device you’re using, and where you’re located.