Zero Trust is a security model that assumes that all resources, systems and users on a network are untrusted, even if they are inside a network perimeter.
More simply put : “NEVER TRUST” always “VERIFY”
It means that devices should not be trusted by default , even if they are connected to a permissioned network such as a corporate LAN.
In a Zero-Trust model, access to resources is only granted on a need-to-know basis and is strictly controlled through a combination of network segmentation.
Traditional IT network security is based on the castle-and-moat concept. In caste-and-moat security, it is hard to obtain access from outside the network, but everyone inside the network is trusted by default. The problem with this approach is that , once an attacker gains access to the network , they have free rein over everything inside the system.
This vulnerability in castle-and-moat security systems is exacerbated by the fact that companies no longer have their data at one place. Today, information is often spread across cloud vendors, which makes it more difficult to have a single security control for an entire network.
In today’s digital world, where data is constantly being transferred and shared, network security is more important than ever before. Cyber threats are becoming increasingly sophisticated and organisations must constantly evolve their security strategies to keep pace. One approach gaining popularity is the zero trust model. In this blog, we will explore what zero trust is, how it works, and the benefits of implementing a zero trust network.
What is Zero Trust?
Zero trust is a security model that assumes no user or device is trusted by default. This means that every user, device, and application must be verified and authenticated before being granted access to a network resource. In essence, zero trust is based on the concept of “never trust, always verify.”
The zero trust model was first introduced by Forrester Research in 2010. At the time, it was a response to the traditional network security model, which relied heavily on perimeter defences. In this model, security was focused on keeping threats out of the network through firewalls, intrusion prevention systems, and other boundary security measures. However, as more and more applications moved to the cloud, and users began accessing network resources from outside the corporate network, the perimeter became more porous, and the traditional security model became less effective.
Zero trust takes a different approach. Rather than relying on perimeter defences, it assumes that threats can come from both inside and outside the network, and that all network traffic must be inspected and authenticated before being allowed to access any network resource. This is done through a combination of authentication, authorization, and encryption.
How Does Zero Trust Work?
Zero trust is based on the principle of least privilege. This means that every user and device is given only the minimum level of access necessary to perform their job function. This is in contrast to the traditional network security model, where users are often given wide-ranging access to network resources.
To implement zero trust, organisations must first identify all the network resources that need to be protected. This can include servers, databases, applications, and other sensitive data. Next, they must classify these resources based on their sensitivity and importance. For example, a database containing customer credit card information would be classified as highly sensitive, while a marketing website would be considered less critical.
Once network resources have been identified and classified, access controls can be put in place. This includes authentication and authorization protocols, as well as data encryption. Authentication can be done through a variety of means, including multi-factor authentication, biometric authentication, and single sign-on. Authorization controls can be based on user identity, device identity, location, and other factors.
Encryption is also an important part of zero trust. All network traffic should be encrypted using secure protocols such as TLS or SSL. In addition, data should be encrypted at rest, meaning that it is encrypted when stored on servers or other storage devices.
Principles of Zero Trust
The zero trust model is based on several key principles, including:
Never trust, always verify : This is the core principle of zero trust. It assumes that no user or device should be trusted by default , and that all network traffic must be authenticated and authorised before being allowed to access any network resource.
Least Privilege : This principle states that every user and device should be given only the maximum level of access necessary to perform their job function. This is in contrast to the traditional network security model, where users are often wide-ranging access to network resources.
Micro-Segmentation : This principle involves dividing the network into smaller segments, and applying controls to each segment. This makes it more difficult for an attacker to move laterally through the network.
Data Encryption: This principle involves encrypting all network traffic, both in transit and at rest. This helps protect sensitive data from being intercepted or stolen.
Continuous Monitoring : This principle involves monitoring all network traffic , both inbound and outbound, in real time. This helps detect and respond to threats more quickly.
Benefits of Zero Trust
The zero trust model offers several benefits over traditional network security models. These include:
Increased Security: By assuming that no user or device is trusted by default, zero trust offers a more secure approach to network security. This is especially important as more and more organizations move to cloud-based applications and users access network resources from outside the corporate network.
Improved Compliance: Many regulatory requirements, such as PCI DSS and HIPAA, require organisations to implement strong access controls and encryption. Zero trust can help organisations meet these requirements by providing a framework for secure access controls and data encryption.
Better Visibility: Zero trust offers greater visibility into network traffic, allowing organisations to detect and respond to threats more quickly. By monitoring all network traffic, organisations can identify potential threats and take action to mitigate them.
Greater Flexibility: Zero trust is more flexible than traditional network security models. Because it is based on the principle of least privilege
Key principles of Zero-Trust Security Model
Verify explicitly: All users, devices, and systems must be verified and authorised before being granted access to resources. This verification should be done through multiple factors, such as biometric authentication, passwords, and security tokens.
Least privilege: Users should only have access to the minimum amount of resources required to perform their job functions. This means limiting access to sensitive data, applications, and systems to only those who need it.
Assume breach: Assume that an attacker has already breached the system and work on the assumption that any user, device, or network could be compromised.
Micro-segmentation: Divide the network into smaller, more secure segments, with different access controls based on user, device, or application. This can limit the potential impact of a security breach and reduce the attack surface.
Continuous monitoring: Monitor all users, devices, and systems in real-time for any suspicious activity. This includes monitoring network traffic, log files, and other system activity to detect any potential threats.
Overall, the Zero Trust model provides a more comprehensive approach to security by assuming that attackers are already inside the network and focusing on verification, least privilege, segmentation, and continuous monitoring to prevent or limit damage from potential security breaches.
