April 13, 2024

Network Access Control: Securing Corporate Networks in the Modern Era

As organizations increasingly rely on network connectivity, controlling access to corporate networks has become critical for maintaining security and compliance. Traditional firewalls and antivirus alone are no longer sufficient to prevent advanced threats from infiltrating networks and accessing sensitive data. Implementing a robust network access control (NAC) solution provides organizations the visibility and control needed to securely enable access in today’s threat landscape.

What is Network Access Control?

Network Access Control, or NAC, refers to a set of technologies and policies used to monitor and secure access to corporate networks. A NAC system centrally manages and enforces who and what is allowed to connect to the network. Key components of a NAC solution include:

– Device monitoring: NAC solutions have the ability to detect different types of devices connecting to the network, including PCs, servers, phones, tablets and IoT devices. This device-level visibility is critical for access control policies.

– Health checks: Once devices are detected, NAC performs real-time health checks to assess security posture. Checks look for things like updated antivirus definitions, patched operating systems, and configured firewalls. Unmanaged or non-compliant devices can be flagged or isolated.

– Access policies: Organizations define granular role-based access policies that specify who and what devices are allowed on the network, what network resources they can access, and any required security configurations. Policies are enforced upon connection.

– Isolation/remediation: Non-compliant devices detected by health checks will be automatically isolated from the production network until security issues are addressed. Isolation prevents potential infections from spreading until remediated.

– Reporting/auditing: NAC systems provide real-time and historical reporting on network access activity. Admins have full visibility into which users and devices are accessing resources and their security posture over time for compliance auditing.

The Need for NAC

As more employees have moved to remote work due to the pandemic, along with the rise in telecommuting and BYOD trends, networks have become more decentralized and difficult to control. Traditional security tools lack adequate visibility into user devices accessing core systems remotely. NAC was designed specifically to help secure expanded networks perimeters. Key drivers for adopting NAC include:

– BYOD rollout: With more unmanaged personal devices on corporate Wi-Fi, NAC is critical to securely enable BYOD programs by checking policy compliance before granting access.

– Vulnerability management: Failure to patch vulnerabilities is the root cause of many breaches. NAC evaluates endpoint security posture to prevent infections from spreading within the network.

– Compliance mandates: Regulations like HIPAA, GDPR, etc. require controlling who and what accesses sensitive data. NAC plays a key role in demonstrating compliance through continuous monitoring and remediation.

– Threat prevention: Sophisticated malware can infiltrate endpoints unnoticed. NAC isolates potentially infected devices to contain spread until vulnerabilities are addressed.

– Network segmentation: Micro-segmentation policies enforced by NAC allow controlling user/device access permissions down to specific servers or VLANs on a granular level.

– Visibility for IT: NAC gives complete visibility into all devices accessing the network infrastructure. IT admins have awareness and control to address issues proactively.

Implementing a NAC Solution

When starting a NAC implementation, the first steps involve defining policies, performing network discovery, and deploying system components. Policies determine conditional access based on device authentication, security posture checks, user/group attributes, and target resources. Common deployment options include:

On-premises hardware/software appliances: Physical or virtual appliances are deployed at network edge for device inspection and policy enforcement. Provides full control but requires infrastructure spend.

Agent-based enforcement: Endpoint agents assess device compliance and communicate status to centralized cloud-based NAC service. Scales easily but agents must be installed on all endpoints.

Agentless enforcement: Leverages existing 802.1X/MAC authentication infrastructure during network connection to enforce policies without an agent. Simple deployment but limited to Layer 2/3 enforcement.

Cloud-managed NAC: All system management and policy configuration performed via cloud console with centralized visibility. Low upfront costs but reliance on cloud connectivity.

Most organizations take a hybrid approach, starting with agentless enforcement at their network edge, then augmenting with agents for mobile/IoT devices not supporting 802.1X. Over time, visibility and control is expanded to remote and cloud-based assets as well.

Measuring NAC Success

Once deployed, continuous monitoring is required to maintain security posture and demonstrate the value of NAC investment over time. Key success metrics include:

– Remediation rate: Number of devices successfully remediated and granted access compared to those isolated indicates effectiveness of policies at driving compliance.

– Access control compliance: Monitoring compliance with access control policies over time shows ability to sustain secure user/device connections posture over time as the environment evolves.

– Vulnerability reduction: Trending data like number of vulnerabilities per device before/after NAC rollout demonstrates ability to reduce overall risk exposure through continuous assessment.

– Containment effectiveness: During incidents, metrics such as mean time to isolation, containment of threat to subset of endpoints, and reduction of successful infections showcase NAC’s value in limiting breach impact.

– Auditing metrics: Useful for demonstrating compliance through metrics like number of users/devices monitored, policy violations blocked, health checks performed, and reports generated per period.

– Stakeholder feedback: Surveys of IT, security teams and business owners indicate ease of use, visibility improvement, productivity gains from secure BYOD/IoT enablement, and overall satisfaction with NAC investment.

When incorporated as part of a comprehensive security program including awareness training, patch management, and ongoing risk assessments, Network Access Control plays a pivotal role in safely enabling workforce productivity while defending the network perimeter from modern threats. Regular measurement ensures the solution continues delivering value over the long term.

In conclusion, as remote and mobile access become universally standard, implementing network access control has become a necessity for organizations to maintain visibility and control of their perimeter defenses. NAC automates continuous monitoring of security hygiene to rapidly isolate potential infections and enforce user and device level policies. Coupled with integration to other security tools, NAC is a foundational technology for modern zero trust network security strategies.

1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it