PCI DSS Network Segmentation Explained: Quick Guide

The Payment Card Industry Data Security Standard (PCI DSS) sets stringent requirements to protect cardholder data. PCI network segmentation is a vital security measure within this framework, endorsed by the PCI Security Standards Council. It involves dividing a larger network into separate, smaller segments, isolated from the others. 

According to a recent industry report, 37% of all data breaches in 2023 involved payment card data. Network segmentation can help protect stored cardholder data while reducing the annual burden of PCI compliance. This blog post will explore the role of network segmentation in PCI compliance. We'll cover its operational benefits and share the best practices to help you effectively reduce your PCI scope. Let’s begin.

What is PCI DSS Network Segmentation?

Payment card industry data security standard (PCI DSS) network segmentation refers to dividing a larger network into distinct, smaller segments or sub-networks. PCI DSS requires that systems handling sensitive cardholder data be isolated from other network segments that do not process such data. By implementing network segmentation, organizations can maintain secure systems and streamline their PCI DSS compliance efforts.

Network segmentation for PCI DSS purposes involves creating boundaries within an organization’s network. It controls and limits access to and from systems that store, process, or transmit cardholder data. The primary goal is to minimize the number of systems and access points that can interact with sensitive data. This targeted isolation helps manage and mitigate risks associated with data breaches and unauthorized access.

Reducing PCI DSS Scope Through Segmentation

One of the most significant advantages of implementing PCI DSS network segmentation is the reduction in PCI DSS scope. By confining the cardholder data environment (CDE) to smaller areas of the overall network, the number of systems and data subject to PCI DSS requirements is minimized.

This scope reduction simplifies compliance efforts and potentially lowers the costs associated with securing a broader network landscape. Effective segmentation ensures that only the necessary network segments are fortified and monitored for maintaining PCI DSS compliance.

Benefits Of Network Segmentation For PCI DSS Compliance

Network segmentation brings numerous compliance and operational benefits to organizations handling sensitive payment card information. Here are the key benefits that network segmentation delivers in the context of PCI DSS compliance.

1. Reduced PCI DSS Scope and Costs

By isolating systems that directly handle or store cardholder data, businesses can focus their security resources and compliance efforts on a smaller, more manageable area. This targeted approach simplifies the processes involved in securing and auditing these systems, ultimately reducing the costs associated with broad-spectrum compliance measures across the entire network.

2. Lowers Security Vulnerabilities

With network segmentation and strong access control measures in place, the impact of a potential breach is minimized by isolating compromised systems from the rest of the network infrastructure. This approach prevents threats from spreading across segments, leveraging individual segment controls and barriers as part of a robust vulnerability management program.

3. Enhances Surveillance and Oversight

Security teams can tailor their surveillance efforts to the specific needs and risks of each segment. This approach improves the detection of suspicious activities and anomalies and allows for quicker responses to security incidents

4. Flexibility in Security Measure Selection

Network segmentation for PCI compliance provides the flexibility to apply appropriate security measures tailored to each segment's requirements. Different security policies and controls can be implemented depending on the sensitivity of the data or the criticality of the systems within a particular segment.

5. Improved Breach Containment and Business Continuity

In the event of a security breach, the damage can be contained to a single segment, reducing the overall impact on the organization's network infrastructure. Maintaining this level of isolation is critical for protecting sensitive cardholder data and ensuring business continuity.

Best Practices for PCI DSS Network Segmentation

Implementing network segmentation enhances an organization's security posture and compliance with PCI DSS standards. To achieve this, organizations must adhere to a set of best practices. Here are the key practices to follow:

1. Define Access Control

Defining who has access to what data and why is the first step in securing a segmented network. Clear roles and permissions ensure that only authorized personnel can access sensitive cardholder data, reducing the risk of accidental or malicious data breaches. Implementing role-based access control (RBAC) systems can help manage access rights efficiently across different network segments while maintaining other security parameters.

2. Balance Network Segmentation Appropriately

While segmentation is beneficial, over-segmenting can create unnecessary complexity, and under-segmenting can leave vulnerabilities exposed. Segments should be logically organized based on the sensitivity of the data they contain and the business functions they support. This approach minimizes the risk of breaches while ensuring that network performance and maintenance remain manageable.

3. Manage And Limit Third-Party Entry Points

Third parties often require access to network resources, but their entry points can introduce vulnerabilities. To mitigate this risk, limit third-party access to authorized entities only. Use secure, monitored gateways and maintain stringent oversight through continuous auditing and review of third-party permissions and activities.

4. Explore Logical Grouping

Consolidating similar functions and data types into the same network segments can streamline both security measures and compliance efforts. This practice enhances the effectiveness of specific protective measures and simplifies the process of monitoring and maintaining security standards.

5. Conduct Regular Network Evaluations

Regularly test security systems and network segments to identify potential vulnerabilities and compliance issues. These assessments should include penetration testing, compliance audits, and reviews of segmentation logic. This will ensure that all partitions remain optimal in terms of both security and performance.

6. Evaluate The Worth Of Network Assets

Understanding the value of the data and resources within each network segment can guide the allocation of security resources. High-value assets should be protected by more stringent security measures and placed in highly secure segments. This risk-based prioritization helps optimize security spending and effort.

7. Establish Endpoint Security Protocols

Endpoints can be the weakest link in network security, especially in a segmented environment. Endpoint security measures such as advanced malware protection, comprehensive patch management, and stringent access controls can prevent network compromises.

Learn how Strac’s Endpoint DLP can secure every endpoint against data breaches.

8. Adhere To The Principle of Least Privilege

The principle of least privilege should be enforced across all network segments. This practice involves granting users and systems the minimum access levels required to perform their tasks. Such controls are essential for minimizing the potential damage from a compromised account or system within a segmented network.

The most effective approaches to network security and PCI DSS compliance require the integration of a powerful tool like Strac.

How Does Strac Simplify PCI DSS Compliance?

Strac is a cloud-based, SaaS, and endpoint DLP solution that helps automate PCI DSS compliance by securing sensitive cardholder data. It reduces the scope of systems subject to PCI DSS controls and protects the organization on many levels.

• Intelligent Data Discovery

Strac’s robust machine learning accurately discovers and classifies sensitive data like credit card numbers. This allows organizations to map the cardholder data flow and determine which systems are covered by PCI DSS.

• Sensitive Data Masking In Real-Time

When PCI-governed data is detected, it will be masked or redacted in real time. A credit card number, for example, will be hidden from view if pasted into a support ticket.

• Secure Data Sharing With Tokenization

Strac’s tokenization capabilities replace sensitive data with an irreversible token. This allows the original PCI-governed data to be securely stored while only the tokens are used in downstream applications. Tokenization enables secure data sharing with third parties and keeps sensitive information out of systems not authorized to store PCI data.

• Generative AI Integration In Data Protection

ChatGPT DLP helps secure every interaction by monitoring and instantly redacting sensitive data shared within ChatGPT prompts. This ensures that all communications comply with PCI DSS and other regulatory standards, protecting against data leaks even in AI-driven conversations.

• Seamless Integration With Cloud And SaaS Environments

The ease of integration into existing cloud and SaaS applications makes Strac an ideal solution for organizations with segmented network architectures. Whether protecting data in Salesforce, managing sensitive information in Google Drive, or securing communications in Slack, our no-code integration handles it all.

Book a demo to discover more about PCI DSS compliance and overall security.