Network Access Control, or NAC, is used to control or limit end user access to the network. NAC enforces access through predefined policies and rules, thereby improving the network’s security posture, and reduces risks of cyberattacks and data breaches by preventing malware and unauthorized access.
Key aspects of NAC:
Policy Enforcement. NAC enforces policies like requiring devices to have an antivirus software and up-to-date signature, up-to-date software patches, and absence of applications that the organization deems unfit in the network.
User and Device Authentication. NAC, using methods like 802.1x or Certificate-based authentication, verifies user and device identity before granting access.
Access Control. NAC restricts access to network resources via Role Based Access Control (RBAC), preventing unauthorized access to sensitive information. It effectively segments the network by placing users in role based vlans. User access can also be implemented thru use of Web Login Captive Portal.
Does NAC have any benefit?
Organizations or enterprises can benefit from implementing NAC in the network. This is the first layer of network defense. Benefits can include:
- Enhanced security posture
- Compliance to regulatory requirements
- Visibility into the types of hosts that are connected into the network
- Automating incident response
- Reduce risk of cyberattack by preventing malware at the edge
- Block unauthorized access.
Common NAC use cases
Manage Bring Your Own Device (BYOD). With the proliferation of workers preferring to use their own devices than enterprise issued devices, the network must make sure that the user owned device meet security policies before being allowed access to the network. Policies may include requirements such as devices being up-to-date with software patches, up-to-date antivirus signatures, and presence of endpoint security.
Securing Internet of Things (IoT) Devices. IoT devices are connected to the network. They have an ip address and mac address, to facilitate communication in the network. As such, attackers can use them to gain entry into the network. NAC can help secure the network from these often overlooked endpoint by profiling for device type, apply access control policies, and check for security posture. NAC reduces the risk of these devices getting exploited by attackers.
Provide Limited Privilege Access to Guest Users and Contractors. NAC can provide limited, secure and controlled access for contractors and guests to the network. Access is granted based on what they need, ensuring they can only access areas of the network where they actually need to.
Zero Trust Security. NAC aligns with company’s Zero Trust Policy, requiring authentication and checks for every user and device before access is granted.
Cloudvision AGNI
CloudVision Arista Guardian for Network Identity (AGNI) is Arista’s cloud-native identity-based network access control. It supports Single Sign-On (SSO) thru integration with major Identity and Access Management (I AM) products. It’s user interface allows monitoring and management from a single pane of glass.
So why choose CloudVision AGNI? If you are looking for a NAC solution designed for the future of security, like password-less, more secure way of authenticating users and devices, e.g. digital certificates, then CloudVision AGNI is the way. It was designed to be simple, software-defined, with focus on ease of use and reduced operational cost.
Summary
It is advisable to include Network Access Control (NAC) in the enterprise’s security solution as the initial point of control before infected or vulnerable devices can gain access to the network. Stopping threats at the edge is always a better solution.
Here’s a basic NAC tutorial using a digital whiteboard—great for beginners who want a clear, visual intro to how Network Access Control secures enterprise networks.
