What Is Network Access Control and Why Do You Need It?

What if someone could waltz into your house whenever they pleased? No doors are locked, no ID is required, and no questions are asked. They’d take what they please and maybe even knock over a vase or two on their way out. 

This sounds terrifying and silly at the same time, so we'll at least add a door to this equation. Let's say the burglar knocks on your door this time to get inside. You might have even personally identified them at the door before letting them in.

But what happens if you’re in a corporate office with hundreds of employees and visitors coming in and out daily? You would set security systems to ensure that your office isn’t compromised. 

Now, imagine you’re trying to protect your office’s network. You need several ways to authenticate visitors, which brings us to network access control software.

Say your corporate network requires one password to access it. This single form of authentication, called a network security key, might work for home networks where you share it with family members.

But a robust modern take on cybersecurity is required for businesses to protect access to their office network. Network access control sets conditions that devices must meet, or they are not given access to the network. NAC can also trace the origin and points of entry that are compromised in post-admission cases.

Why is network access control important?

With each advancement within the field of cybersecurity, hackers adapt to new measures. Sometimes, the risk isn’t just people outside the organization.  There might be employees with malicious intent or plain ol’ incompetence.

New technologies bring a learning curve. And while that isn’t inherently bad, it’s essential to factor in that you might not know everything there is to know about a new software before jumping into it. Think of the cloud. It was a game-changer for businesses across the globe. However, it has its risks and security needs.

Network access control deals with cybersecurity threats and provides the protection business networks require. Let’s consider some things to keep in mind while choosing your NAC software.

Protects business assets

Within network security, an asset is a piece of valuable information stored within the network. This could include employee identification details or medical records.

Having a network security system in place reduces the number of security breaches and helps companies bounce back from them more quickly.

Maintains regulatory compliance

Network access control technology helps organizations comply with government policies and industry-specific rules and regulations about data security. These regulations include the Health Insurance Portability and Accountability Act (HIPAA) and the Payment Card Industry Data Security Standard (PCI-DSS).

Enables safe workplace collaboration

Most organizations use online communication to exchange information among employees. Network security ensures that employees can collaborate in the workplace without worrying about whether their sensitive data is protected.

How does network access control work?

Network access control is a security solution that uses protocols and policies to implement rules to determine which users and devices can access the network.

Based on traffic flow, we know that non-compliant devices and users are denied access to the network. It also lets you dictate how much network you want certain users to access. For example, not all your employees require access to the entire network. This means you can grant different levels of access to employees based on user roles.

Network access control largely consists of a two-step process of authentication and authorization. They are quarantined if a device or user fails these two steps.

Authentication is the door to your network. It prompts the user to enter credentials to authorize entry into the network. This could be a pin, a code, or a username and password.

After authentication, the user is authorized based on the security policies set by the organization. Access won’t be granted if the user or device doesn’t comply with established policies.

Network access control components

Network access control mainly consists of policy management and enforcement features but also includes better visibility and analytics of visitors who have accessed the network. Several components can be involved in most NAC technologies depending on the use case.

Endpoints

An endpoint is a spot where two devices interact in a network. Think laptops or internet of things (IoT) devices. Issues with endpoint security harm the entire network because they could serve as a gateway for hackers to access your information.

Network access control keeps endpoints as one of the critical factors to monitor. You can safeguard clients by using a good antivirus and firewall for protection.

Client software

Applications on your devices can also be entry points into a network. Network access control architecture considers applications for authentication, as these can be easy targets for hackers via malware and other cyber threats.

Authentication server

This server is part of the remote authentication dial-in service (RADIUS). It’s responsible for checking the credentials of the devices and asking for permission. The authentication server is vital to NAC solutions.

Sometimes, credentials like username and password are enough. But for corporate networks, behavior-based authentication needs to be considered to prevent unauthorized access.

Authenticators

The authenticator uses the authentication framework to communicate between the endpoints and the authentication server.

The authenticator controls the managed switch, which keeps clients marked as unauthorized by default until it receives a confirmation from the authentication server. From here, it can proceed to access the network or won’t be allowed in at all.

Quarantine

Quarantine is a space where client devices or software that were once allowed to access the network are now unauthorized due to post-admission network access control policies and policy enforcement.

Guest networks

These are essential for organizations with many non-payroll employees or third parties such as consultants and vendors. Creating a guest network helps prevent third parties from accessing irrelevant information about their work.

Corporate networks

These networks are the main channel for communicating within the organization. Only traffic authorized by the authentication server should be able to access the network. This does mean that you should apply additional security measures to the corporate network to ensure that there is no breach of the sensitive information you’re sharing. 

Management console

Network access control is managed through a security dashboard, stored on-premise or on the cloud. The advantages of this console include device visibility, security policy configurations, network traffic trends, and security alerts. 
It’s a one-stop security management console accessible through web portals or apps on your desktop or mobile device.

Client agent

While these are optional, client agents empower employees to self-assess their device’s security posture and to keep an eye out for suspicious activity. These aren’t a substitute for the security management console, but they can help quickly remove vulnerabilities.

Types of network access control

     Four types of network access control exist today.

• Pre-admission network access control ensures that a device isn’t granted access to a network if it does not meet policy conditions. Most network access control solutions use this type.
• Post-admission network access control applies policies after a client has access to the network. This is usually an incident response, like if new threats are detected from the client or the NAC policies have been updated and the device no longer meets the necessary conditions. Network access control can also be set up based on the decision-making mechanisms existing within the network.
• Out-of-band solutions use a policy server that communicates with network devices, such as switches and routers, to regulate traffic. This policy server isn't within the flow of network traffic; therefore, it’s out-of-band.
• Inline solutions are called inline because – you guessed it – the policy server sits within the traffic flow. These require significant resources, as the server simultaneously decides whether to allow traffic as it goes through the flow.

Benefits of NAC

If you’re still not clear about the advantages of NAC software, keep reading for a few more examples of how it can benefit your company.

• Simplifies troubleshooting: NAC solutions are designed to make security management for your network more accessible. It lets you quickly analyze traffic trends and data with the help of visual representations such as charts, graphs, and data maps. It also has advanced search and event management features that speed up troubleshooting.
• Automates responses: Network access control can mitigate threats without admin responses. These automated responses are based on predefined policies so action can happen in real time.
• Provides threat intelligence: NAC tools use an access control list of prohibited users and devices. The software continuously updates this list to block traffic coming from malicious sources.

Top network access control use cases

We know that NAC is a vital network security solution ecosystem. But what are some of the use cases you can implement into your business network?

Guest and partner access

Sometimes you might need to provide access to guests and other non-employees. Network access control software separates a guest network from the leading visitor network. The software takes their credentials here, but they only have internet access. This means that no sensitive company information falls into the wrong hands.

BYOD

If your company has a bring-your-own-device (BYOD) policy, it can be challenging to track which devices meet your security standards or whether they’re malicious. Network access control solutions stop BYOD policies from affecting your network security negatively.

With NAC, you can choose only to allow access to clients who meet the policy conditions. Here’s also where the quarantine segment comes in handy – after personal devices are set up to be secure, they can reaccess the network.

IoT devices

Internet of Things (IoT) devices include laptops, cell phones, printers, closed-circuit television cameras, and automation-heavy devices like light and motion sensors. They’re usually unaccounted for, thus making them the most vulnerable to hackers.

But since network access control profiles clients well, it can send IoT devices to another specialized server. This removes personal intervention and keeps outsiders from accessing essential data on your enterprise network.

Gaps in network access control solutions

As with any technology, some common issues relate to authentication and poorly monitored and maintained devices. Knowing the gaps, NAC can bring to security systems helps troubleshoot issues before they become business threats.

Bad password hygiene

While tough passwords are excellent, people share or write them down to make remembering them more manageable. But doing these things poses an imminent security risk and should be avoided.

With the help of multi-factor and two-factor authentication, employees don’t have to worry about remembering passwords that sound like you’re Mary Poppins making up gibberish words for English schoolchildren.

New software, new problems

Issues arise whenever you implement new software to combat network security gaps. People who want to harm themselves always find a workaround for network security protocols unless the vulnerabilities are taken care of immediately.

Constant monitoring of your management console and keeping up with the latest security trends are required in today’s climate.

Easy targets galore

Every unsecured device connected to your network is an endpoint open to malicious attacks. It would be difficult to keep track of every device in an extensive and complicated network. A great way to battle endpoint security issues is to use remote access control; each device can be supervised continuously.

Differences between NAC and firewall

Even though NAC tech and firewalls share similar concepts, they differ significantly.

Endpoint vs. network-focused

Network access control sits at the endpoints of a network, acting as a gatekeeper for every user that tries to cross over. 

A firewall is usually located between two networks to allow them to communicate. Think inter-network security versus intra-network security.

Dynamic vs. static policies

Network access control has multiple dynamic criteria to categorize endpoints. For example, if the operating system is not up to date, that could lead to the device being quarantined within the NAC loop.

Firewall policies are made through static criteria called five tuples. This includes source and destination IP addresses, ports, and protocols.

Keep your network secure

Network security is critical to protect valuable data and sensitive information. The lack of a robust and secure network system can cause identity theft, stolen assets, and reputational harm.

With network access control, you can keep your company information private and manage your network hassle-free.

Want to read more on how hackers can gain access to your network? Learn about zero-day vulnerability and how it affects network security.