With the ever-increasing threat of cyberattacks, defenses against these threats need to be continually scrutinized and improved upon. The United States government’s response to this has been to move toward a zero trust principle, which will shape the way leading cybersecurity standards evolve moving forward. But what does it mean to architect and configure a zero trust network? This guide will introduce the core principles of the zero trust approach, how they can be applied to a digital security strategy, and what to consider when making the transition.
What is a Zero Trust Network?
Zero trust is an approach to cybersecurity in which trust is always being evaluated. Rather than designating trusted entities that need to be authenticated when requests are made, each access attempt is treated as if it’s coming from a potential threat. A zero trust network, therefore, is one in which architecture, access policies, and workflow are built upon zero trust concepts.
An effective end-to-end zero trust architecture incorporates:
- Analyzing real-time user activities, events, and other data to keep network defenses prepared
- Authenticating, monitoring, and evaluating the trustworthiness of user identities
- Controlling and managing data access
- Securing and accrediting applications
- Supporting both IPv4 and IPv6
- Using automated monitoring and scanning tools
What Are the Goals of Zero Trust Architecture?
According to the National Institute of Standards and Technology (NIST), the zero trust cybersecurity strategy is intended to support “least privilege per-request access decisions” in the context of a network that’s being treated as compromised. The goal is to grant the absolute minimum necessary privileges necessary for tasks to be completed, which reduces the amount of uncertainty that can arise when managing permissions in a complex network environment.
Zero trust architecture aims to focus on using robust, technology-agnostic identity and access controls rather than perimeter-based defenses—such as network firewall security—to better mitigate unauthorized access to sensitive data, targeted phishing attacks, and other threats while facilitating productivity and allowing for the use of cloud-based solutions.
The Basics of Zero Trust Security
The tenets of zero trust represent the ideal outcomes of the implementation of the strategy.
The exact architecture of each organization’s implementation, however, is bound to look different, so these tenets aren’t meant to serve as an absolute truth of how an effective zero trust environment has to look. The basic tenets of zero trust comprise the following points:
- A network may include several types of devices, and all sources of data and services are considered resources.
- Trust should never be automatically granted and all communications should be secured regardless of where the network is located.
- Access to any resource should be granted on a per-session basis and follow the least privilege principle.
- How access is granted should be defined by a written policy that should be updated as needed.
- No asset should be trusted, and the integrity of all assets should be consistently monitored.
- The cycle of authenticating and authorizing requests to access resources should be constant, dynamic, and strictly enforced.
- Collect and log as much data regarding network and user activities and access requests as possible, and use it to improve security measures.
How to Apply Zero Trust to a Network
When designing a zero trust network, apply the tenets along with the following considerations:
- The private network is not considered a trust zone, therefore all activities should be carried out with the assumption that the network is compromised.
- Devices not owned by or accessible to the organization may be connected to the network.
- No resource is trusted, therefore security posture must be evaluated with each access request and through the duration of the session.
- Resources might be located outside the organization’s IT infrastructure.
- Remotely-located resources should regard their local network as non-trusted.
- Anything transmitted between the organization’s infrastructure and other environments should maintain its security policy and posture.
Potential Vulnerabilities and Threats in a Zero Trust Network
Zero trust architecture aims to achieve more robust security, but that doesn’t mean a zero trust network is invulnerable to threats. Rather than eliminating all risks, zero trust helps mitigate them, so it’s critical to remain aware of the types of threats that your network could still face.
Potential vulnerabilities to remain aware of in a zero trust environment include:
- Denial-of-service attacks
- Network disruption
- Compromised credentials
- Internal attackers
- Network visibility
- Stored information about the environment
- Proprietary solutions and data formats
- Nonhuman accounts
Just as zero trust dictates that trustworthiness should never be assumed, it should always be assumed that environments, assets, and resources could potentially be compromised.
Implementing a Zero Trust Network
As with any security framework, implementing zero trust is a complex process, and the details of how that process looks will vary from one organization to the next. Nevertheless, there are several best practices and considerations that benefit all zero trust implementations.
Here are the primary things to focus on when deciding to transition to a zero trust network:
A thorough understanding of the principles and goals of zero trust architecture is essential to having a successful, effective implementation. It’s also critical to understand the existing architecture, components, and risks in the existing IT environment.
Spend time learning the principles of zero trust and how a zero trust network will differ from your organization’s existing architecture.
Identify all accounts that operate within the network. This includes both human users and nonhuman accounts, such as services. Document the level of privileges of existing users and evaluate what level of access they need moving forward. Be prepared to restrict privileges, but aim to do so without hindering the ability to complete tasks.
Pay close attention to the balance between privileges and responsibilities when handling administrator and developer accounts.
Having the ability to identify and manage devices is one of the primary requirements of zero trust architecture. This includes devices owned by the organization, external devices that connect to the network or access resources within the network, and nonhardware assets.
Examples of assets to identify include:
- Desktop computers and laptops
- Phones and mobile phones
- Servers and routers
- Digital certificates
Beyond cataloging assets, it’s essential to monitor, configure and manage them over time.
Take inventory of processes and data transmission flows and evaluate how they contribute to the goals of the organization. Organize them based on how critical they are to overall operations. This can help narrow down which processes would be best to start with when transitioning to zero trust. Starting with lower-risk processes can help limit disruptions and serve as practice before moving on to processes that have higher stakes.
Processes that rely on cloud-based resources can also be a good place to start, as transitioning them to zero trust is highly likely to improve security.
Identify existing vulnerabilities within your organization’s environment and evaluate how much risk they pose to systems, networks, and data. Project how these risks could be mitigated by the transition to zero trust and prioritize those that could be addressed most easily and with the least amount of potential added risk.
Rather than trying to immediately maximize risk reduction, focus on small steps and gradual changes that can be made to incorporate the principles into the existing security strategy.
Choosing a Target Operating Model
After inventorying and evaluating the existing state of your organization’s network, decide the initial goal for the transition to a zero trust network.
Though every implementation will be unique, there are two general models to consider:
- Total zero trust architecture – In most cases, a fully zero trust architecture will be untenable. But in cases where an entirely new infrastructure needs to be built, it could be a good opportunity to consider whether pure zero trust would be possible.
- Hybrid zero trust and perimeter-based architecture – In most cases, a blend of zero trust and perimeter-based security is going to be the most realistic option to migrate to. But even seemingly small changes can require significant redesign, so the transition should be gradual and should only be advanced to the next step when existing changes have been evaluated and verified for efficacy.
Any security strategy should be policy-driven, and zero trust is no exception. Refer to the data gathered during the initial planning phases of the transition to identify what assets or processes to focus on initially. Identify any resources that are associated with or affected by the selected assets and resources to prioritize further. Develop policies to define how the selected assets and processes will be managed and secured moving forward. These policies should also dictate the criteria that will be used for evaluating potential solutions that may be needed.
Policies should be dynamic but persistent. Adjustments and updates will be needed over time to keep up with evolving threats and security standards. However, policies should remain intact and applicable regardless of where an asset exists or process runs relative to the network.
New network architecture and new security policies will most likely affect everyone working within the organization’s environment. Provide ongoing education and training on what’s expected in a zero trust environment and how it will affect the way personnel will carry out tasks and support the security of the environment on a day-to-day basis.
Education and training are crucial elements of any security program and can help mitigate internal threats that could emerge due to lack of awareness.
Identifying Potential Solutions
Zero trust is meant to be technology agnostic, meaning that each organization needs to evaluate and select the most appropriate solutions to implement zero trust architecture into the network based on its unique environment and the needs of the organization. Here are a few questions to keep in mind when considering solutions for a zero trust network implementation:
- Will the solution require changes to existing processes?
- What applications, protocols, and services are supported?
- How thorough are the logs generated by the solution?
- Can the solution be used regardless of where it’s located relative to the network?
- What automation is built into the solution?
Seek solutions that will be most compatible with the existing architecture and that, ideally, will require minimal redesign.
Designing and Deploying Architecture
Be diligent about any necessary redesign to facilitate the implementation of zero trust architecture into the network. Consider any changes in processes, policies, the removal of any assets or resources, and the addition of new solutions. Start by deploying in an observational mode to identify any adjustments that need to be made before officially implementing the changes. RSI Security’s managed network security services will provide and maintain a custom solution to ensure your organization’s network is secured against emerging threats.
Monitoring and Assessing Systems
Continue monitoring for a time after the zero trust network implementation. Log activity to identify patterns and establish a baseline against which activities can be evaluated moving forward. This is crucial to identifying unusual activity with greater ease.
Perform network penetration testing and other evaluations to assess how the implementation is performing compared to its previous iteration, and allow sufficient time for the new architecture to be proven effective before considering further changes.
Rather than a single event, implementing zero trust architecture is an ongoing process.
Start slow with small changes, and make additional implementations over time. Implementing zero trust architecture gradually will ensure a sustainable migration with less disruption and a reduced risk of undesired effects during the process.
Get Help Managing Your Zero Trust Network Implementation
As technology continues to advance, the cyber threats that your organization may face will only continue to grow more sophisticated. And the increasing complexity of networks—which may include remote assets and cloud-based resources—only makes things more complicated.
Robust identity and access management practices can be one of the most crucial aspects of keeping a network secure, but it can also be one of the most challenging. Privilege creep is a common problem that can weaken security. Zero trust principles aim to address this and other security issues by asserting that no component, resource, or account is inherently trustworthy and by requiring continuous, session-based authentication and authorization.
But while zero trust aims to simplify authentication and authorization by making it a universal requirement, that doesn’t mean implementing a zero trust strategy is an easy task.
Contact RSI Security today to learn how zero trust can strengthen your organization’s network.