Zero Trust vs. Defense-In-Depth: What's the Difference?

What are the differences between Zero Trust and Defense in Depth? The term “Zero Trust” has been gaining a lot of traction in recent years, but what does it actually mean? In short, Zero Trust is a security model that advocates for never blindly trusting any entity within or outside of an organization. This is in contrast to the more traditional “Defense in Depth” approach, which relies on layered security controls to provide protection.

While both can be very effective, there are reasons why many companies are more in favor of Zero Trust. Let’s take a closer look at Defense in Depth vs. Zero Trust.

What is Zero Trust?

Zero Trust is a security model that emphasizes the need to verify every user and device before granting them access to company resources. This verification process is continuous, ensuring that only authorized users and devices are given access – even if they originate from inside the organization.

What is Defense in Depth?

Defense in Depth (DiD) is a security strategy that employs multiple layers of security defenses to protect data and systems from attacks. The goal of DiD is to make it difficult for attackers to penetrate the outer defenses, and, even if they do, to make it hard for them to move laterally and access sensitive data.

Zero Trust vs Defense in Depth

So, what’s the real difference between Zero Trust and Defense in Depth? When it comes down to Defense in Depth vs. Zero Trust, which is the best option for your organization?

The main difference is that Zero Trust requires continuous verification of users and devices, whereas Defense in Depth relies on multiple layers of security defenses. Additionally, Zero Trust focuses on protecting data and systems from external and internal threats, while Defense in Depth mainly focuses on external threats.

The Disadvantages of Zero Trust

There are a few potential disadvantages of using a Zero Trust security model:

1. It can be costly to implement and maintain. Largely, this occurs when organizations attempt to adopt a Zero Trust model internally, with their own internal resources, rather than hiring an expert specialist to manage their journey.
2. It can slow down the user experience, as every user and device must be verified before being granted access. Unfortunately, this can inhibit productivity. But the right configuration and the right technology can reduce productivity and efficiency issues.
3. It may be difficult to implement in large organizations with complex networks. Zero Trust security models do “distrust by default,” which also means that organizations must monitor and manage their security processes with greater levels of depth.

The Advantages of Defense in Depth

Defense in Depth has a few potential advantages over Zero Trust:

1. It is less resource-intensive to implement and maintain. Defense in Depth is inherently a simpler security model when compared to Zero Trust, which means it's also easier to maintain.
2. It does not slow down the user experience, as only external users and devices need to be verified. The trade-off is that Defense in Depth doesn't provide as much security as the Zero Trust model.
3. It can be easily implemented in large organizations with complex networks. Many organizations move to adopt Defense in Depth because it can be implemented and scaled with ease. But by the same token, that scaling doesn't future-proof the organization, because the level of protection simply isn't there.

The Disadvantages of Defense in Depth

On the other hand, there are a few major disadvantages of using a Defense in Depth security strategy:

1. It can be difficult to coordinate multiple layers of security defenses. The Defense in Depth strategy isn't quite a holistic one; it involves multiple separate layers which must then be implemented, managed, and maintained.
2. It may provide a false sense of security, as attackers may only need to bypass one layer of defense to gain access to sensitive data. Attackers are simply more likely to breach a Defense in Depth strategy because there are multiple layers of security defenses and because the outer layers may be easier to peel.
3. It can be costly to implement and maintain, especially if multiple security products are used. Over time, a Defense in Depth strategy can become more expensive, as each security product has to be separately maintained and may become more expensive over time due to licensing costs.

The Advantages of Zero Trust

In many cases, Zero Trust may be a better security strategy than Defense in Depth. Here are a few advantages that Zero Trust has over Defense in Depth:

1. Zero Trust can provide better protection against internal and external threats. Zero Trust defaults to the best level of security possible, exposing an extraordinarily limited attack surface.
2. Zero Trust can be easier to implement and maintain. Even though there are some challenges, when you use a security partner, it can actually be easier to implement and maintain — even if it's harder to implement and maintain for the average business.
3. Zero Trust can help improve the user experience. Zero Trust is easier for end-users, for the most part. Users may get frustrated with some Defense in Depth systems, but Zero Trust can be essentially invisible to the end-user when properly constructed. However, again, the major concern is having the Zero Trust network properly constructed by a security professional.
4. Zero Trust can be more cost-effective in the long run. Zero Trust involves fewer parts, making prices less likely to jump up unexpectedly. A Zero Trust system really only requires that the organization follow the Zero Trust philosophy with their software solutions.

So, which Is Better? Zero Trust vs. Defense in Depth

It's easy to see why some companies may be hesitant to embark upon a Zero Trust security model. As a comprehensive security model, it can take some time to adopt and adapt to. But with the help of a trusted security partner, the process becomes much easier.

At the end of the day, Zero Trust is a better security model. The benefits far outweigh the drawbacks. Contact Axiad to find out more about how the Zero Trust authentication model can work for you.