The Practical Guide To Building A Zero-Trust Architecture

Vinod Joseph
October 27, 2021

Understanding Zero-Trust

Zero-Trust is a security model built to prevent systems from trusting any device by default. The approach requires devices to be re-verified at every instance to prevent a system from being breached. The concept behind the model is to avoid vulnerabilities at all points by removing protocols that trust devices and allow them to connect to a network automatically. This means that even when a device is connected to a network or is verified previously, access to the system would not be offered without strict identity verification at every instance.

Zero-Trust architecture is also known as perimeter-less network security. Conventional security protocols operate within a perimeter, built to protect the network only from external threats. This leaves gaps in network security since the users and devices which fall within the perimeter can still comprise the system. 

Therefore, Zero-Trust architecture achieves higher security standards by protecting the network from both internal and external vulnerabilities.

The need for Zero-Trust Architecture

In our increasingly connected world with sky-high internet adoption rates, the flow of information is the highest and fastest it has ever been. 

Further, the ongoing COVID-19 pandemic forced a vast majority of the workforce into remote work, generating more internet traffic. This has meant that teams have migrated to the cloud to be able to work from their homes, and as a result, are exposed to a higher number of cyber threats. 

Now that the employees who were working within the secured perimeter of an office complex are working from their homes, it is harder for businesses to control the flow of data. The use of unregulated networks and unsecured devices have left access to information unchecked. This makes enterprise assets vulnerable to cyber threat actors. 

Zero-Trust architecture allows an enterprise to extend security to any user and device provided they are verified. This approach not only closes loopholes in the cybersecurity infrastructure but is also more efficient at creating a secured network.

What does Zero-Trust bring to the table?

Zero-Trust uses dynamic policies to manage access to business data. Since users and devices are verified for every session, another attempt to access information can only be successful through verification. 

Further, with every new session the identity of the user, as well as the user environment and behavior, are assessed to determine the integrity of the access request, adding another layer of security to enterprise data.

Moreover, Zero-Trust architecture is programmed to accept encrypted and authenticated communications only. This prevents potential threats from ever reaching the company assets.

How to build Zero-Trust architecture

A Zero-Trust security network can be built through some fundamental changes in traditional cybersecurity practices. As more organizations adopt a Zero-Trust architecture, other players must catch up to maintain a competitive edge. Here is how an enterprise can develop Zero-Trust architecture for their network:

1. Beginning - Most vulnerable points

The first step to building Zero-Trust architecture is identifying the vulnerabilities in the system and possible origins of breaches to prevent access. An ideal approach to achieve this is to assign controls to users based on their roles at the enterprise. This is generally coupled with multi-factor authenticated access to ensure that only legitimate users can gain access to company data.

2. Access management for devices

Managing access for devices is at the core of Zero-Trust. It allows an enterprise to ensure that only the devices and assets that are owned or deemed legitimate are provided access to the system. Even then, all access is subject to due verification. 

Zero-Trust uses the principle of least privilege, which extends only the lowest level of access to each user and device by default. This prevents network lateral movement barring threat actors from moving deeper into the network in search of sensitive information. 

3. Access management for networks

An enterprise must manage access to its network through the use of multiple devices and permissions to limit who can access the network. The use of different switches coupled with routers to create different micro-segments within the network where separate protocols can be deployed to protect data must be encouraged. Security teams can use access control lists (ACLs) to limit the communication of users within the network.

4. Access Policy

An important part of Zero-Trust architecture is the creation of a policy that will determine the type of access that can be granted to different entities. The policy must clearly define which users can access the network through what applications and for what reason. It must then demarcate when a user and/or device can or cannot access the network or parts of it. Finally, the policy must provide an outline for what can be accessed and how it can be done.

5. Data management and monitoring

Data is vulnerable no matter if it is at rest or being transferred. Therefore, sensitive information must be encrypted at all instances to avoid the smallest of chances of a breach. 

Since encrypted data, as well, is at risk of being breached, security teams must monitor the network constantly. Teams must proactively review access, logs, traffic and recorded attempts to breach the network. Constant monitoring offers an insight into the vulnerabilities that remain in the system and allow them to be resolved.

How to implement Zero-Trust

The process of implementing Zero-Trust can be arduous. Proponents of the approach do not expect enterprises to renounce all existing security protocols, rather take small steps and gradually augment multiple parts of the system into the architecture. 

Zero-Trust can be implemented over a prolonged period. New protocols can be tested and data be migrated into a perimeter-less network with the view to achieve absolute Zero-Trust in a couple of years.

Final thoughts

A multitude of factors has led to Zero-Trust becoming the need of the hour. A dramatic increase in the use of cloud networks owing to the pandemic was only a successor to the surge in the number of internet users throughout Southeast Asia in the previous decade, and in North America during the decade before that. As systems grow more complex, breaches become more difficult to avoid as well. Therefore, it could be argued that businesses need to assume every entity as a threat and implement a Zero-Trust approach. 

While traditional systems cannot immediately migrate to Zero-Trust architecture, the most sensitive data can be brought within the ambit of perimeter-less network security with other parts of the system to be followed. However, with the eventual goal of creating completely perimeter-less security, Zero-Trust, architecture.