Network Access Control (NAC) plays a crucial role in preventing unauthorized devices and users from gaining access to private networks. With multi-cloud network architecture becoming increasingly popular, NAC is a critical security component, securing access both on-premises and through multi-cloud networks. NAC identifies and evaluates devices, enforces policies, and provides visibility into user activity, which makes it a crucial tool in securing distributed network architectures.

NAC solutions help organizations strengthen their IT infrastructure. They also ensure compliance with regulatory requirements.


Policy-Based network access control (NAC) applies policies to users and devices before they can enter your network. These policies determine what types of network access control are granted and what is denied. In addition, it prevents threats from gaining access to sensitive data.

The policies you create can be IP-address-based, role-based, or both. Role-based policies are easier to manage, scale, and automate. They are also able to handle user and device mobility.

If a policy is breached, you can take steps to remediate it quickly and efficiently. For example, you can revoke access based on the user’s role and re-authorize it with a different profile or identity.

Another way that NAC can help you secure your organization is by limiting access to non-employee devices and users. It can ensure that any viruses or other security threats cannot infiltrate your organization from unauthorized devices.

You can even configure NAC to allow third-party applications to communicate with your network security and only access the necessary data. It is essential for organizations that have a large ecosystem of external services.


Network access control (NAC) restricts unauthorized users and devices from gaining access to corporate networks. It enables an organization to enforce endpoint security policies by monitoring network traffic and evaluating the credentials of the device or user requests to access the network.

Pre-admission NAC applies NAC policy before a device or user is granted access to the network. It evaluates the device or user’s request, assessing its origin, behavioral pattern, and credentials to allow or deny access based on policies.

Post-admission NAC applies policies after a device or user is granted access to a particular network zone. As a result, it prevents lateral movement inside the enterprise perimeter and mitigates cyber attack damage.

NAC identifies threats before they breach the enterprise perimeter and attempts to stop them before they gain further lateral movement into privileged assets. This defense-in-depth approach is critical to securing an organization’s data, systems, and services.

NAC solutions are designed to apply policies based on the type of device or user, its location and usage, and its posture. Sometimes, agents on end devices or within the network infrastructure use scanning and inventory techniques to identify these characteristics. In contrast, others use a policy server outside the device’s path of traffic.


Network access control (NAC) is limiting access to a network to users or devices that are authorized and compliant with security policies. Organizations use NAC to prevent unauthorized devices from connecting to the corporate network.

In pre-admission NAC, a device or user attempting to enter the network must prove their identity by authenticating themselves. Then, the system assesses the request and allows or denies access based on the information provided by the device or user.

While in post-admission NAC, a device or a user must again prove their identity to gain authorization when attempting to move to a new zone within the network. It is designed to restrict lateral movement within the network and reduce cyber attack damage.

Many NAC products include a quarantine feature, a sandbox environment where traffic carrying non-authenticated credentials is placed until remediation can be performed. It prevents the end user from interacting with or damaging external files and protects the business.

Some users preferred to implement post-admission NAC instead of pre-admission NAC for two reasons:

First, some customers feel that their routine patching and updating processes are compelling enough that catching the occasionally infected device is not worth the added protection. In addition, some customers believe they will see more severe problems with post-admission than with pre-admission NAC.


Network access control (NAC) is a security solution that enables an organization to prevent unauthorized users and devices from accessing its private networks. It can protect the network from malware and other security threats by enforcing security policies based on device, user, location, and other factors.

NAC solutions automate assessing a device’s posture and compliance with corporate security policies. It is done by examining a device’s operating system version, firmware version, and other attributes to detect any non-compliant behaviors or suspicious activities.

Sometimes, a device can be blocked from connecting to the network altogether, or the connection can be limited so that only compliant devices can access it. NAC solutions also automatically quarantine a device that has not updated its operating system or security patches and, when possible, update the device to comply with a company’s security policies.

With BYOD rules and third-party or contractor agreements, the number of endpoints on an organization’s network is increasing rapidly. This increased number of connected devices requires organizations to monitor and comply with corporate security policies constantly.

NAC can identify and profile every device that connects to a network, and it can automatically assess the security posture of those devices. This visibility can help an organization develop its endpoint security policies and respond to various networking and security events.