Network segmentation: How secure zones protect your IT

Today, hacks and data theft are commonplace, with companies reporting compromised systems and blackmail almost daily. IT security is critical for all organizations, and network segmentation is an increasingly important security strategy.

Segmentation organizes IT networks into secure areas with strictly controlled access. Imagine your company network as a building: without segmentation, all the doors are wide open. This creates an easy target for intruders, allowing them to move freely from room to room and cause chaos wherever they go.

Separate zones with access controls, on the other hand, severely restrict hackers. Even if attackers take over an area, the other segments are spared. Why? Intruders are restricted in their movements; they cannot spread throughout the network. This is exactly the principle that network segmentation takes advantage of.

A study by security firm Akamai titled “State of Segmentation 2023 report” found that almost all (93%) respondents consider segmentation – broadly recognized as an important element of zero-trust frameworks – critical to thwarting ransomware attacks. However, deployment appears to be slow, with only 30% of organizations segmenting across more than two business critical areas in 2023.

Segmentation: Separate zones isolate critical systems

Dividing the network into separate zones protects confidential data and sensitive systems much better. Whether production processes, company secrets or customer and financial data: Even if attackers gain access to part of the network, these crown jewels remain under lock and key in their own, highly secure segments.

Ultimately: The smaller and more manageable a network segment, the easier it is for IT teams to keep track. Suspicious activities are noticed more quickly, problems can be contained and resolved more quickly if they are limited to one segment. The effort for management and monitoring decreases.

Segmentation also relieves bandwidth as traffic per zone decreases. Less traffic in each area leaves more bandwidth for everyone. Resources can be allocated in a more targeted and needs-based manner. If new departments or services are added, IT can simply add more segments without having to disrupt the entire network.

Micro-segmentation, a variant of network segmentation, takes the principle to the extreme: It isolates even the smallest units such as individual apps or workloads. This greatly increases protection in complex, dynamic environments such as the cloud.

IT security: Contain the attack vectors and lateral movement 

IT security benefits most from well thought-out network segmentation. Confidential data can be stored in separate zones and thus better protected. If, for example, accounting, administration, IT and production work in separate segments, a successful attack on the office network does not automatically give hackers access to production systems.

Dividing the network into isolated areas also reduces overall attack vectors. If an intruder gains control of systems in a segment through malicious code, they cannot easily spread to other zones. In unsegmented networks, on the other hand, all devices and users potentially have access to all resources. After penetrating the network defenses, attackers move almost freely and hijack other systems with minimal effort. Blackmail Trojans also infect and encrypt significantly more computers.

Last but not least, segmentation also makes it easier for companies to comply with legal data protection requirements. Whether it's the European General Data Protection Regulation (GDPR) or the US Health Insurance Portability and Accountability Act (HIPAA): More delicate access control through separate network zones simply protects sensitive information better.

Least Privilege: Access control restricts attackers

Curbing lateral movement is one of the biggest plus points of segmentation. Attackers often spend weeks or months undetected in compromised networks. During this time, they explore the environment, search for valuable data and prepare for the next attacks. The freer they can move, the greater the potential damage.

Segmentation takes this leeway away from them. It creates additional hurdles and barriers to overcome. At the same time, it enables much finer access control. Admins can precisely determine who or what is allowed to access which areas. The principle of least privilege can be implemented much more consistently. This granular access control method also paves the way for Zero Trust architectures that ensure maximum security by not trusting anyone.

How to implement network segmentation successfully

Most companies use a combination of VLANs and ACLs as well as firewalls and VPN solutions for network segmentation. The logical separation and access control within the segments are carried out by Virtual Local Area Networks and Access Control Lists. Firewalls and VPNs, on the other hand, regulate access between the segments. At the beginning of a segmentation strategy, however, there is always careful planning and analysis of the IT landscape:

• What systems, applications and data are there?
• Who needs access to which resources?
• What are the dependencies?

With the answers to these questions, you can develop a segmentation concept that is tailor-made for your company. But beware: When it comes to technical implementation, you should definitely let experienced experts take the helm – whether from your own ranks or from external service providers such as NCP. Because even small mistakes have fatal consequences here. A gaping gap in the firewall, incorrectly configured access rules or ineffective segments could put your IT at risk.

Ultimately: Just because segmentation is in place doesn't mean you can skimp on monitoring and analyzing your traffic. It’s quite the opposite. Without intrusion detection systems and intrusion prevention systems, you won't be able to detect attacks in time. IDS and IPS are on the lookout for suspicious patterns and anomalies in your network traffic. If they detect a threat, they sound the alarm immediately.

Network segmentation is a powerful weapon, but not a panacea. It can support other security measures but never replace them. Only by cleverly combining your lines of defense will you be able to protect your entire business. Monitoring tools such as IDS, Security Information and Event Management (SIEM) or traffic analyses play just as important a role as clever segmentation.

In a nutshell: Network segmentation is essential for IT security

Network segmentation works like fire partitions in a building: Targeted insulation creates a robust architecture for the protection of critical areas. Companies reduce the risk of cyber attacks, at the same time improve the performance of their network and facilitate the management of their IT infrastructure.

Robust IT security is a must – and network segmentation is a key component for this. With NCP’s solutions, you are well prepared for the challenges of the future, even when it comes to segmentation. In our central management software, you can precisely define which users, groups and applications are allowed to access which network resources. Learn more about this topic here:

The perfect building block for your Zero Trust concept