Network Access Control (NAC): Why is it important?

Business networks are changing rapidly, causing new threats to emerge and creating unknown risks that network managers need to consider. Remote working is now routine, with around 45% of Americans working at home full-time or part-time. Cloud storage accounts for approximately 50% of corporate data worldwide, while the number of IoT-connected endpoints reached 12.3 billion in 2021, and projections suggest it will reach 27 billion by 2025. These changes have made it vital to secure network devices and control perimeter access. Network Access Control (NAC) is one solution to this problem, but what is it, and how can companies benefit from NAC implementations?

What is Network Access Control (NAC)?

Network access control is the act of keeping unauthorized users and devices out of a private network. Organizations that give certain devices or users from outside of the organization occasional access to the network can use network access control to ensure that these devices meet corporate security compliance regulations.

The increasingly sanctioned use of non-corporate devices accessing corporate networks requires businesses to pay special attention to network security, including who or what is allowed access. Network security protects the functionality of the network, ensuring that only authorized users and devices have access to it, that those devices are clean, and that the users are who they say they are.

Network access control, or NAC, is one aspect of network security. There are many NAC tools available, and the functions are often performed by a network access server. Effective network access control restricts access to only those devices that are authorized and compliant with security policies, meaning they have all the required security patches and anti-intrusion software. Network operators define the security policies that decide which devices or applications comply with endpoint security requirements and will be allowed network access.

How does Network Access Control work?

NAC solutions function by establishing which devices and users are authorized to connect to wired and wireless networks. Security teams devise a protocol that forms the basis of authorization policies, and specialist software applies those protocols every time a connection request is received. NAC systems refer to third-party authentication services when they receive access requests and establish user permissions. When the system authenticates users, it creates secure connections that resemble classic Virtual Private Network (VPN) tunnels.

NAC tools may also determine which resources are available to corporate network users. Security policies can set out different access tiers depending on user roles, and NAC software can make it impossible for users to move outside their allotted permissions. This architecture provides several capabilities for network managers, making threat management much more manageable.

What is the importance of Network Access Control?

NAC is critical for modern businesses because it allows organizations to monitor the devices and users — authorized and unauthorized — trying to access the network.

Unauthorized users include cybercriminals, hackers, data thieves, and other bad actors that an organization must keep out. But businesses must also be gatekeepers for authorized users. This particularly applies to organizations that allow remote access to the enterprise network from non-corporate devices like mobile phones, laptops, and tablets, or companies that allow employees working in the office to use personal devices. Both scenarios create security risks demanding organizations to address network security.

NAC is one aspect of network security. It provides visibility into the devices and users trying to access the enterprise network. It controls who can access the network, including denying access to those users and devices that don’t comply with security policies. NAC solutions and tools help companies control network access, ensure compliance, and strengthen their IT infrastructure.

What are the general capabilities of a NAC solution?

NAC solutions help organizations control access to their networks through the following capabilities:

• Policy lifecycle management: Enforces policies for all operating scenarios without requiring separate products or additional modules.
• Profiling and visibility: Recognizes and profiles users and their devices before malicious code can cause damage.
• Guest networking access: Manage guests through a customizable, self-service portal that includes guest registration, guest authentication, guest sponsoring, and a guest management portal.
• Security posture check: Evaluates security-policy compliance by user type, device type, and operating system.
• Incidence response: Mitigates network threats by enforcing security policies that block, isolate, and repair noncompliant machines without administrator attention.
• Bidirectional integration: Integrate with other security and network solutions through the open/RESTful API.

Common use cases for NAC

NAC enables an organization to manage access to its network and IT resources. Some common use cases for NAC include:

• Bring Your Own Device (BYOD): As remote work and BYOD policies become more common, devices not owned by the business will increasingly have access to corporate data, systems, and services. NAC enables an organization to ensure that these devices are compliant with corporate security policies before allowing them to access the corporate network.
• Internet of Things (IoT) Devices: IoT devices can bring significant benefits to the business and its employees, but they also have significant security issues, making them a common target for cybercriminals. With NAC, an organization can restrict IoT devices’ access to corporate assets, decreasing the impact of a compromised device.
• Guest/Contractor Access: Guests and contractors may have a legitimate need for access to an organization’s network but do not need access to everything. NAC solutions can limit guests’ and contractors’ access to only what is needed for their role.
• Infected Device Containment: Malware on infected devices may attempt to spread laterally through the corporate network. NAC solutions can block this spread by quarantining these devices on the network.

All Businesses Need Network Access Control (NAC)

Although each business is unique and approaches NAC individually, it is important to keep the various users and devices in mind and accounted for at all times. Most businesses do have a few key requirements when choosing NAC, which include preventing unauthorized users and devices from accessing the network, creating a log of each access event, and keeping a record of everything in a central and easily accessible location. It is also important to ensure that remote users understand the company’s security policies and that NAC serves as a backup to enforce those policies.

Finally, IT leaders need a solution that quarantines unhealthy or compromised machines. NAC includes enhanced access controls that minimize the risk of lateral movement and provide visibility and protection over your network environment.