The Fundamentals of Network Access Management

With cyber threats constantly evolving, securing your network is more than just strong passwords or firewalls-it's ensuring that the right people have access to the right resources at the right times. Understanding and implementing effective network access management is the cornerstone of protecting valuable data and maintaining operational efficiency.

In this blog post, we explore the fundamentals of network access control and management, including its core features, benefits, and the top solutions on the market.

Network Access Control vs. Network Access Management

Network access control (NAC) is a security solution that enforces policies for controlling device access to a network. It ensures that only authorized devices and users can connect to network resources and that these devices comply with security policies before gaining access. It is focused on controlling access to network resources, network nodes like routers, switches or firewalls.

Network access management, on the other hand, is a broader concept that encompasses the overall strategy, policies, and technologies used to control and manage network access. It includes NAC as a component but also involves other aspects of network management. Key features of NAM include policy development and enforcement, access provisioning and deprovisioning, and monitoring and reporting. NAM is also tightly integrated with Identity Governance and Administration (IGA), ensuring access rights are adequately aligned with organizational policies and compliance requirements.

Importance of Network Access Control

Network access control is critical to a secure and compliant IT ecosystem. NAC solutions control access by authenticating users and devices and assessing their compliance with security policies before allowing access to the network. When a device attempts to connect to the network, NAC determines what level of access, if any, should be granted based on criteria such as the user's role, the device type, the location of the request, and the device's security status.

Why do you need Network Access Control?

Robust network access control is essential to any modern cybersecurity and regulatory compliance strategy. One reason is the increasing number and diversity of devices that need network access today. With the advent of the Internet of Things (IoT), the volume of devices accessing networks has skyrocketed. Each device, from a simple office printer to sophisticated servers, is a potential entry point for external attackers and internal threats, whether accidental or deliberate. Also, without NAC there is no network segmentation possible.

The sheer volume of these devices makes it impractical, if not impossible, to oversee network access manually, so a comprehensive NAC strategy that leverages automation is vital. The capabilities of NAC solutions have evolved to address the growing complexity of IT environments, including the increasing diversity of user devices, the rise of remote and mobile access requirements, and the proliferation of IoT devices.

In addition, NAC systems help enforce regulatory standards by ensuring that devices accessing the network comply with data protection and privacy laws.

Core features of Network Access Control

A comprehensive network access control strategy involves the following NAC features:

Policy Engine

NAC solutions typically employ a central policy engine that uses access control policies. These security policies can include criteria such as user roles, device types, location, time of day, and device security posture. They can be pretty granular, specifying access permissions at the user, device, or application level.

Endpoint Assessment

NAC assesses the security status of devices attempting to connect to the network before approving access. This can include checking for antivirus software, operating system patches, firewall settings, and other security configurations. Devices that fail to meet security requirements may be quarantined or given limited access until they comply.

Network Enforcement Points

Network enforcement points are switches, routers, wireless access points, VPN gateways, firewalls, and other network entry points. They enforce NAC policies based on the policy engine's decisions.

Network Monitoring, Profiling and Reporting

NAC systems continuously monitor network traffic and activity to identify and profile devices connecting to the network for unauthorized access attempts, policy violations, and security incidents. This gives administrators real-time visibility into network access, user behavior, and compliance status. Detailed logs and reports help in forensic analysis, compliance auditing, and security incident response. Behavioral analysis and fingerprinting techniques help identify devices based on their network communication patterns and characteristics.

Authentication and Authorization Mechanisms

Upon connecting to the network, users and devices undergo authentication to verify their identities. After authentication, NAC determines the appropriate access permissions based on the user's identity, device characteristics, and other contextual factors. Authorization decisions are made in real-time according to the access control policies defined by the policy engine.

User Authentication Methods

Examples of user authentication methods include:

• Users provide a unique username and corresponding password to authenticate themselves.
• Users must provide multiple forms of authentication, such as a password combined with a temporary code sent to their mobile device.
• Users present digital certificates issued by a trusted Certificate Authority to prove their identity.
• Users authenticate using physiological characteristics like fingerprints, iris scans, or facial recognition.

Device Identification Methods

Methods for identifying devices include the following:

• MAC addresses uniquely identify network interfaces on devices.
• Internet Protocol (IP) addresses uniquely identify devices on a network.
• Devices present digital certificates to authenticate themselves to the network.
• Device characteristics such as operating system, device type, and vendor are used to identify devices.

Guest and BYOD Access

NAC provides mechanisms for managing access for guest users and bring-your-own-device (BYOD) scenarios. Guest users may be granted limited access to specific resources based on defined policies. BYOD devices undergo device profiling and security assessment before being granted access, with access permissions determined based on the device's compliance status.

Dynamic Access Control

NAC can dynamically adjust access permissions based on changing conditions in the network environment. For example, if a device's security posture deteriorates because its antivirus software is disabled, NAC may restrict its access until the security issue is remediated.

Quarantine and Remediation

In cases where devices fail security assessments or violate access policies, NAC may quarantine them to prevent further network exposure. Quarantined devices are placed in a restricted network segment with limited access until they comply with security policies. Remediation mechanisms help bring non-compliant devices into compliance by providing instructions or automated fixes.

NAC integration with existing network infrastructure

To control access, NAC solutions typically integrate with the following network components:

• Switches and routers - NAC solutions often integrate with network switches and routers to enforce access control policies at the network edge. Integration with switches allows NAC to dynamically assign VLANs or apply access control lists (ACLs) based on user and device authentication status. Routers may enforce access policies for remote access VPN connections to ensure that only authenticated users can connect to the network.
• Wireless access points (WAPs) - NAC solutions integrate with wireless infrastructure to enforce access control policies for Wi-Fi networks. WAPs use protocols such as IEEE 802.1X to authenticate users and devices before granting access to the wireless network. Integration with NAC allows WAPs to apply access policies based on user identity, device type, and security posture.
• Firewalls - NAC solutions can integrate with firewalls to enforce access control policies for traffic entering and leaving the network as well as network segmentation within. Firewalls may use user and device authentication information from the NAC system to apply granular access control rules based on user roles, device types, and other contextual factors.
• Identity and access management (IAM) systems - NAC solutions integrate with identity management systems like Active Directory and LDAP to streamline user authentication and authorization processes and ensure consistency across the organization.
• Security information and event management (SIEM) systems - NAC solutions integrate with SIEM systems to provide centralized monitoring and reporting of network access events. Integration with SIEM allows NAC to correlate access control events with other security events and alerts, enhancing visibility into potential security threats.
• Endpoint security solutions - NAC solutions may integrate with endpoint security solutions such as antivirus software, endpoint detection and response (EDR) systems, and mobile device management (MDM) platforms. Integration with these solutions allows NAC to assess devices and enforce access control policies based on their security status.

Benefits of implementing NAC

Implementing network access control offers several benefits for organizations seeking to enhance cybersecurity and manage network access effectively. NAC helps mitigate the risks associated with unmanaged devices accessing corporate resources. Below are some key advantages.

• Enhanced security posture - By verifying user identities and assessing devices before granting access, NAC helps reduce the risk of data breaches and downtime.
• Improved compliance - By controlling and auditing network access, NAC helps organizations achieve, maintain, and demonstrate compliance with GDPR, HIPAA, PCI DSS, and other regulations.
• Faster threat detection and response-By continuously monitoring network activity, NAC helps IT teams detect potential security threats in real-time. NAC can also automate response to threats by quarantining devices that pose a security risk to prevent them from accessing sensitive network resources until the issue is remediated.
• Better visibility and control-NAC gives administrators real-time visibility into network access activity, device types, and compliance status. This visibility enables them to identify and respond to security incidents more effectively and proactively improve security policies. It also allows for network segmentation and the control thereof.
• Streamlined onboarding processes - NAC helps streamline the onboarding process for new users and devices by automating user authentication and device registration. This reduces the administrative burden on IT staff and ensures that new users and devices are onboarded securely and efficiently.
• Support for BYOD initiatives - NAC facilitates secure BYOD initiatives by enforcing access controls and security policies for personal devices connecting to the corporate network.
• Optimized network performance-By dynamically adjusting access permissions based on user roles, device types, and security posture, NAC helps optimize network performance and bandwidth utilization. It also ensures that network resources are allocated efficiently and prioritized based on business requirements.
• Centralized policy management - NAC provides a centralized platform for defining, managing, and enforcing access control policies across the organization. This simplifies policy management, ensures consistency, and reduces the risk of misconfigurations and policy conflicts.

Types of NAC solutions

There are three basic types of NAC solutions: hardware-based, software-based, and cloud-based. Each type has advantages and considerations, and organizations should evaluate their specific requirements, network architecture, and security objectives before selecting the most suitable solution.

Hardware-Based NAC Systems

Hardware-based NAC solutions are usually appliances purpose-built for access control and security enforcement. They may include specialized hardware components for processing authentication, authorization, and policy enforcement tasks.

Dedicated appliances offer predictable performance and reliability, making them suitable for mission-critical network environments. They are often deployed inline within the network infrastructure, allowing them to intercept and inspect network traffic in real-time.

In addition, hardware-based NAC systems are designed to scale to support large numbers of users and devices across distributed network environments. These systems offer high throughput and low latency, ensuring minimal impact on network performance even under heavy traffic loads. They may support clustering or high-availability configurations for redundancy and fault tolerance.

Software-Based NAC Solutions

Software-based network access control solutions utilize software applications or virtual appliances. These solutions offer flexibility, scalability, and ease of deployment. They allow organizations to deploy NAC functionality as needed and scale resources based on changing network requirements, making them suitable for various network environments. Software-based NAC solutions can be deployed on-premises in private or hybrid cloud environments.

Software-based NAC solutions may support both agent-based and agentless deployment models:

• Agent-based NAC - Agent-based NAC solutions require the installation of software agents on user devices. These agents collect information about the device's security posture and enforce access control policies based on this information. Agent-based NAC solutions offer granular control and visibility into individual devices but may require additional overhead for agent deployment and management.
• Agentless NAC - Agentless NAC solutions do not need software agents installed on user devices. Instead, they use network-based mechanisms such as IEEE 802.1X authentication, DHCP fingerprinting, or network traffic analysis to assess device security posture and enforce access control policies. Agentless NAC solutions offer ease of deployment and scalability but may have limitations in visibility and control compared to agent-based solutions.

Cloud-Based NAC Solutions

Cloud-based NAC solutions are built on cloud-native architectures and leverage cloud infrastructure for scalability, reliability, and performance. These software-as-a-service (SaaS) offerings eliminate the need for on-premises hardware or software deployment and offer zero-touch deployment, enabling organizations to deploy access control functionalities quickly and easily. Resources can be scaled up or down based on demand, ensuring optimal performance and cost-efficiency.

Cloud-based NAC services also provide global reach and accessibility, allowing organizations to enforce access control policies for users and devices regardless of location. Users can securely connect to corporate resources from anywhere worldwide, including remote offices, branch locations, and mobile devices. Cloud-based NAC services integrate with cloud-based and on-premises network infrastructure components, ensuring seamless connectivity and access control across hybrid environments.

Critical considerations for deployment of NAC solutions

Implementing an NAC solution requires careful planning, configuration, and testing. Key elements for success are detailed below.

Assessment and Planning

Identify and document the objectives for deploying NAC. Thoroughly assess the network infrastructure, including hardware, software, and network topology. Determine the scope of deployment, including the number of users, devices, and network segments to be covered. Identify specific use cases and scenarios where NAC will provide value, such as securing remote access, enforcing BYOD policies, or ensuring compliance with regulatory standards.

Budget and Resources

Evaluate the budget and resources required for NAC deployment, including hardware/software costs, implementation services, training, and ongoing maintenance. Consider the total cost of ownership (TCO) and return on investment (ROI) to justify the deployment.

Policy Definition

Define access control policies based on organizational requirements, security best practices, and compliance regulations. Consider user roles, device types, location, time of day, and security posture. Define policy rules for user authentication, device profiling, role-based access control, and enforcement actions (e.g., quarantine, remediation). Be sure to document access control policies in a centralized policy repository for easy reference and management.

Selection of NAC Solution

Evaluate NAC solutions based on their features, integration capabilities and compatibility with existing network infrastructure and potential network expansions in capacity (device and user) or technology (being agnostic about network vendors). Also, consider the deployment model (hardware-based, software-based, or cloud-based), vendor support, and cost-effectiveness.

Deployment Architecture

Design the deployment architecture for NAC, considering network topology, traffic patterns, and security and compliance requirements. Determine whether NAC enforcement points will be deployed inline or out-of-band and whether they will be deployed at network access points, within, or both.

Integration with Network Infrastructure

Determine how to integrate NAC solutions with existing network infrastructure components, including switches, routers, firewalls, authentication servers, IAM systems, and endpoint security solutions. Also, plan to integrate NAC with network security solutions like your intrusion detection system (IDS), intrusion prevention system (IPS), and SIEM platform.

User and Device Profiling

Configure access control policies in the NAC solution based on the defined policy rules and requirements. Define user roles, device types, and authentication requirements based on organizational needs and security policies.

Testing and Validation

Conduct thorough testing of the NAC deployment in a controlled environment to validate its functionality, performance, and security: test access control policies, authentication mechanisms, device profiling, endpoint security assessment, and policy enforcement capabilities. Address any issues discovered during testing before deploying NAC in a production environment.

Deployment and Rollout

Deploy NAC in a phased approach, starting with a pilot deployment in a small, controlled environment. Based on the pilot deployment's results, gradually expand the deployment to additional network segments, users, and devices.

Monitoring and Maintenance

Monitor the NAC deployment regularly to ensure ongoing compliance with access control policies, security requirements, and performance objectives. Use the NAC solution's monitoring and reporting capabilities to monitor network access activity, security alerts, and policy violations.

In addition, regular maintenance tasks, such as software updates, patches, and configuration changes, must be performed to ensure the continued effectiveness and security of the NAC deployment.

User Awareness and Training

Provide users and IT staff with training on the purpose and benefits of NAC deployment. Educate them on complying with access control policies and security measures enforced by the NAC solution.

Challenges in implementing Network Access Management

As you prepare to implement network access control, be sure to consider the following challenges that organizations often encounter:

• Complexity of network infrastructure - Modern network environments are increasingly complex, comprising various devices, platforms, and connectivity options. Managing access across this heterogeneous landscape can be challenging because it requires expertise securing different systems and technologies.
• Diverse user and device types - Organizations today have diverse user populations, including employees, contractors, guests, and partners, each with varying access requirements. Similarly, device types have expanded beyond traditional workstations and servers to include IoT devices and an array of BYOD endpoints. Managing access for these diverse users and devices while maintaining security is a significant challenge.
• Remote and mobile access - With the rise of remote work and mobile computing, ensuring secure access to corporate resources from anywhere, at any time, has become crucial. Managing access for remote and mobile users requires robust authentication mechanisms, encryption, and endpoint security measures to mitigate the risk of data breaches and downtime.
• Compliance requirements - Network access management must adhere to the provisions of stringent regulations such as GDPR, HIPAA, and PCI DSS. Ensuring compliance with these regulations while maintaining a balance between security and usability can be challenging, particularly in highly regulated industries.
• User experience and productivity - While security is paramount, implementing overly restrictive access controls can lead to user frustration and inefficiencies. Organizations often struggle to balance security and usability.
• Scalability and performance - Scalability and performance are critical considerations, especially for large organizations with extensive user bases and network infrastructures. NAC solutions must scale to accommodate growth and fluctuating user loads while maintaining optimal performance and responsiveness.
• Emerging technologies and threats - Rapid technological advancements like cloud computing, IoT, artificial intelligence (AI), and machine learning (ML) introduce access management challenges and security threats. NAC solutions must adapt to these emerging technologies and provide robust protection against evolving cyber threats.
• Integration challenges - NAC solutions must seamlessly integrate with existing network infrastructure components, identity management systems, security tools, and other IT systems. Achieving interoperability and smooth integration can be complex, requiring coordination between vendors and technologies.
• Need for continuous monitoring and adaptation-Network access management is an ongoing process that requires continuous monitoring, analysis, and adaptation to evolving threats and business requirements. Keeping up requires constant vigilance and investment in training for both IT teams and business users.
• Resource constraints - Implementing NAC requires significant resources, including time, budget, and skilled personnel. Limited resources may hinder the deployment process and impact the effectiveness of NAC implementation.
• Resistance to change - Resistance to change by various stakeholders can pose a significant obstacle to NAC implementation. Business users may resist new authentication methods or access control policies, while IT staff may be reluctant to adopt unfamiliar technologies or workflows. In addition, senior management may not lend sufficient support for NAC initiatives because they do not fully appreciate the need for change.
• Legacy systems - Legacy systems or outdated network infrastructure may not fully support NAC requirements, posing compatibility challenges and limiting the effectiveness of NAC implementation. Upgrading or replacing legacy systems may be necessary to overcome these obstacles.

Basic network structure technologies

As businesses continue to evolve, the demand for flexible, scalable, and secure network solutions has driven the development of advanced network technologies. Key among these technologies is the following:

• Software-Defined Networking (SDN) decouples the control plane from the data plane in networking equipment. By centralizing network intelligence in a software-based controller, SDN provides enhanced programmability, automation, and flexibility. This enables network administrators to dynamically manage network resources and optimize traffic flow, leading to improved efficiency and reduced operational costs.
• Network Functions Virtualization (NFV) transforms traditional network functions, such as firewalls and load balancers, into virtualized services that run on standard hardware. This virtualization reduces the reliance on proprietary hardware, allows for more agile service deployment, and facilitates scaling of network functions to meet changing demands. NFV is integral to modern network infrastructures, offering a more flexible and cost-effective alternative to traditional network appliances.
• Micro-segmentation divides a network into granular segments, each with its own set of security policies. Unlike traditional segmentation that isolates larger network segments, micro-segmentation allows for more precise control over east-west traffic within a data center. This approach minimizes the attack surface and enhances security by ensuring that even if one segment is compromised, the breach is contained.
• Network Segmentation involves dividing a larger network into smaller, distinct segments to improve performance and security. By isolating different parts of the network, segmentation reduces the risk of widespread attacks and allows for more effective traffic management. It also helps enforce access controls, ensuring that sensitive data remains protected and only accessible to authorized users.

These advanced network structure technologies collectively contribute to creating more secure, efficient, and scalable network environments. They empower organizations to better manage their resources, protect sensitive data, and respond quickly to evolving business needs.

Trends and Emerging Technologies Influencing NAC

Below are some emerging trends and technologies that are likely to influence NAC:

• Zero Trust-The Zero Trust security model is rapidly gaining traction among organizations. It grants no trust by default, requiring strict identity verification and minimal privilege access controls for every user and device attempting to connect to the network. NAC plays a crucial role in enforcing Zero Trust principles by continuously verifying user and device identities and adjusting access permissions based on contextual factors.
• Artificial intelligence and machine learning-AI and ML technologies are being integrated into NAC solutions to enhance threat detection, anomaly detection, and behavior analysis capabilities. AI-powered NAC solutions can identify suspicious activity, detect emerging threats, and automatically adapt access controls in real-time to mitigate security, compliance, and business continuity risks.
• Endpoint security integration - NAC solutions are increasingly integrating with endpoint security technologies, such as endpoint detection and response (EDR), antivirus, and endpoint protection platforms (EPP), to enhance visibility, enforce security policies and respond to endpoint-related security incidents. Integration with endpoint security solutions enables NAC to assess the security posture of devices and implement access controls based on risk levels.
• IoT and OT device security - The proliferation of IoT and operational technology (OT) devices presents new security challenges for network access management. NAC solutions are evolving to support the unique requirements of IoT and OT environments, providing device discovery, profiling, and access control capabilities to secure these endpoints and prevent unauthorized access.
• Emphasis on user experience - Technologies such as contextual authentication, adaptive access policies, and self-service portals will enable organizations to ensure smooth and frictionless access to network resources without sacrificing security.

Network access control is essential to protecting against cyber threats and achieving compliance with regulations and industry standards. Core aspects of NAC include gaining comprehensive visibility into all devices and users connecting to the network and developing policies that protect security without compromising the user experience. Organizations also need to provide frequent training sessions to enhance user security awareness. Choosing an NAC solution with robust integration features enables the full capabilities of the security stack, enhances threat detection and response, and streamlines security operations.

FAQ

What is NAC, and how does it work?

Network access control (NAC) is a security practice focused on controlling access to a network based on factors such as the identity, security posture, and compliance status of devices seeking to connect. NAC solutions, such as switches, routers, and wireless access points, are typically deployed at network entry points to enforce security policies.

What is the difference between a firewall and NAC?

A firewall and a network access control system serve different but complementary purposes in network security:

• A firewall is a software or hardware security system that functions as a barrier between a trusted internal network and untrusted external networks like the Internet. Firewalls regulate incoming and outgoing network traffic according to defined security rules that use factors like IP addresses, port numbers, and protocols, and they often use stateful inspection to track the state of active connections. Firewalls can be installed in PCs, routers, hardware appliances, and other locations.
• NAC is a security discipline that focuses on controlling access to a network based on the identity and security posture of the devices seeking access. It typically involves a combination of hardware and software solutions that enforce security policies, such as requiring devices to have up-to-date antivirus software, operating system patches, or specific configurations in order to be granted network access. NAC systems often include features such as authentication mechanisms, endpoint security checks, and integration with other security systems like identity management platforms.

What is NAC used for in networking?

Network access control (NAC) is used primarily to enhance security by controlling access to a network based on factors such as the identity, security posture, and compliance status of devices seeking access. Before allowing access, NAC systems identify and assess devices, and they often authenticate users to add another layer of security.