The Ultimate Guide to Network Access Control (NAC)
Network access control (NAC) solutions monitor and control access to corporate networks and the devices connected to them. NACs enable companies to define policies to manage potential network security risks associated with bring your own device (BYOD) policies, the Internet of Things (IoT), and remote work. This ability to granularly manage access reduces the risk that insecure devices will be allowed access to corporate networks, and enables companies to better enforce security policies.
Table of Contents
Key Capabilities and Benefits of NAC Solutions
NAC solutions enhance corporate cybersecurity and compliance by managing which devices can access the corporate network and the resources that they are permitted to access. Some vital capabilities that NAC solutions require to fulfill their role include the following:
- Device Profiling: NAC solutions can profile a device, collecting unique identifiers and information about its current security posture. This data can be used to apply access control policies and assess whether the device should be permitted onto the corporate network and the systems associated with it.
- Policy Enforcement: Policy enforcement capabilities are a key component of a NAC’s role within the organization. An organization may implement policies that require devices to have certain security protections in place, such as a corporate antivirus. Using its profiling capabilities, the NAC solution can determine whether a device complies with applicable policies and should be granted access to the network.
- Access Control: NAC solutions have deep visibility into access requests and the ability to control that access based on corporate policies. For example, an organization may define controls that prevent IoT devices from connecting to other corporate systems or limit access to sensitive and high-value resources to on-prem or trusted devices.
Top Use Cases for Network Access Control
NAC solutions provide visibility and policy management for access requests on the corporate network. Some applications of these capabilities include the following:
- Remote Work and BYOD: Remote work and BYOD introduce new security threats for an organization since unmanaged and potentially insecure devices are granted access to corporate systems. NAC helps organizations to manage their risk exposure by ensuring that remote workers’ devices are compliant with corporate policies and denying access to those that are missing patches or not running required security software.
- Third-Party Support: Some companies have vendors, partners, suppliers, and other third parties who require limited access to the corporate network to fulfill their roles. However, granting unrestricted access could expose the organization to supply chain attacks. NAC enables the organization to grant limited access to these third parties based on the level of access required and the perceived threat to the organization (i.e. if a device appears insecure or potentially compromised).
- Securing IoT Devices: Many organizations have a growing number of IoT devices connected to their networks; however, these systems commonly have poor security and are prime targets for cybercriminals. NAC solutions limit the potential threat to an organization’s security by restricting these devices’ access to other corporate systems and potentially sensitive data.
- Regulatory Compliance: Regulations such as PCI DSS mandate that organizations limit access to systems that access and process sensitive information. NAC helps organizations achieve and demonstrate compliance by limiting access to these devices and providing the visibility required to demonstrate this control during compliance audits.
What are the Types of Network Access Control?
NACs implement access management for the corporate network and IT resources. They can do this in a couple of different ways, including:
- Pre-Admission: Pre-admission NAC solutions act as gatekeepers to the corporate network. Before a device is permitted to connect to the network, it is inspected and validated by the NAC solution. This ensures that only authorized devices can access corporate resources.
- Post-Admission: Post-admission NAC solutions authenticate and authorize devices as they move between zones within a segmented network. This type of NAC provides internal visibility and can help to protect the organization against lateral movement by cyber criminals who have gained a foothold on the corporate network.
Post-admission NAC offers superior protection and visibility when compared to pre-admission NAC since it implements access control both on initial entry to the network and when moving between network zones. The additional visibility that it provides is essential for implementing zero trust policies and offers the organization additional opportunities to identify and block intruders before they achieve their objectives and cause damage to the organization.
Evaluating and Selecting the Right NAC Solution
Some key considerations to keep in mind while evaluating candidate NAC solutions include the following:
- Business Requirements: NAC can be applied to various use cases, ranging from supporting remote work to securing an IoT deployment. When selecting a NAC solution, it’s important to consider the business requirements and how they can impact the selection process. For example, a post-admission NAC solution provides protection against threats using insecure IoT devices as an entry point to a corporate network, while pre-admission doesn’t.
- IT Integration: NAC solutions must be capable of achieving a certain level of network visibility and control to fulfill their purpose. When evaluating available solutions, it’s important to validate that they can integrate with an organization’s firewalls, intrusion detection and prevention systems (IDS/IPS), and other elements of its network and security infrastructure.
- Security Posture: The right NAC solution may also depend on an organization’s security posture and goals. For example, an organization pursuing zero trust will definitely require a NAC with post-admission capabilities to monitor and validate every access request.
- Compliance Requirements: Regulations and standards commonly mandate that an organization control access to sensitive data and systems. Any NAC solution selected by a business should be capable of both enforcing corporate security policies and complying with the requirements of relevant regulations.
- Deployment Location: As companies’ cloud usage expands, a NAC will be increasingly responsible for managing access to cloud-based resources. When comparing NAC solutions, an organization should consider whether the NAC has the ability to effectively manage cloud access.
- Financial Constraints: Companies may also have financial constraints that dictate the NAC solutions they adopt. Certain solutions may be more cost-effective over time as the organization’s network grows or shifts.
Best Practices for Implementing a NAC Solution
A successful NAC deployment can dramatically improve corporate cybersecurity and compliance by offering much-needed visibility into and control over access requests. Some best practices that IT leaders should follow when implementing NAC solutions include the following:
- Define Requirements: NAC solutions should be selected to meet business needs, such as improved security or compliance. Identifying the goals of the NAC deployment and the associated requirements is the first step of deployment.
- Perform a Network Inventory: NAC solutions integrate with an organization’s network infrastructure and manage access to IT resources. Performing a full inventory of network assets is essential to implementing the required integrations and ensuring that the solution can effectively provide the required visibility and control.
- Develop Policies: NAC solutions run on policies that define which requests to permit and which to deny. NAC policies should be designed to support business requirements, enforce corporate security policies, and maintain compliance with relevant laws and regulations.
- Plan the Deployment: NAC solutions must be integrated into an organization’s network infrastructure to enforce access controls. During the planning stage, the team should review the desired capabilities and security policies and identify locations where the NAC solution will need to hook in to achieve its goals.
- Perform a Pilot: A pilot or proof of concept is always a good idea when making large-scale changes to an organization’s network and security architecture. Performing a pilot in a realistic environment helps to ensure that the NAC solution operates as intended and can aid in refining the deployment strategy to improve efficiency and address any issues.
- Roll out in Phases: Ideally, the NAC solution should be rolled out in phases to the production environment. This staged rollout helps to limit the effects of any issues and enables later stages to benefit from lessons learned from earlier steps in the process.
- Monitor and Update: NAC solutions provide the greatest benefit to the organization if they are regularly monitored and updated as needed. The team may identify issues with policies, access controls, deployment locations, or other aspects that may require remediation. Additionally, as the corporate network grows and evolves, the NAC solution may require updates to ensure that it provides an adequate level of visibility, protection, and control.
The Future of NAC in a Zero Trust World
Zero trust is the future of security and access control. Instead of implicitly trusting insiders, zero trust requires explicit validation of every access request, regardless of source. This approach provides the organization with a better chance of identifying and addressing threats present within its network.
NAC solutions are a key component of an effective zero trust strategy. By acting as a gatekeeper for the corporate network and its connected resources, NAC provides the visibility and control needed to implement and enforce zero trust security policies. When defining policies for a NAC system, organizations can implement zero trust principles such as least privilege to move closer to a full zero trust architecture.
When implementing NAC — whether for zero trust or not — control over access requests is essential for success. Any traffic that the NAC solution can’t see, it can’t perform policy enforcement on. Cato SASE Cloud simplifies and enhances NAC deployments by implementing zero trust network access (ZTNA) across the entire corporate WAN as part of a converged network security solution.