top of page

Firewall PCI DSS compliance: Requirements & best practices

PCI DSS compliance refers to a set of security measures that apply to businesses handling payment cards, e.g., credit cards, debit cards, and cash cards. The full meaning of the term PCI DSS is Payment Card Industry Data Security Standard.

All companies that accept, process, store, or transmit credit card information require PCI Compliance as it ensures data security during and outside financial transactions.

PCI DSS compliance is the rules and policies companies processing, storing, or transmitting payment card information must adhere to, helping them build a secure environment for card data. The PCI security standards council (PCI SSC) is the body responsible for managing PCI DSS.

PCI SSC was formed in 2006 and has since been providing policies that tackle evolving cyber threats in the payment card industry.

A firewall PCI DSS compliance refers to the process of configuring a firewall to monitor and filter incoming and outgoing internet traffic based on PCI DSS policies.

Firewalls function based on a set of security rules, enabling them to block bad traffic like viruses and hackers from penetrating your network. Establishing a PCI-compliant firewall gives companies robust payment card information security that meets business needs and effectively protects sensitive data.

What is a firewall PCI DSS compliance?

Hackers see credit cards and other payment card types as money-making opportunities. They tirelessly attack systems and networks to extract cardholders’ personal information and sensitive authentication data, which they can exploit. Examples of cardholder data are:

Primary Account Number (PAN)

Cardholder name

Expiration date

Service code

Sensitive authentication data include:

Full track data (magnetic-stripe data or equivalent on a chip)

CAV2/CVC2/CVV2/CID

PINs/PIN blocks

Becoming PCI-compliant means you have effective security solutions to help defend your network against attacks and protect the financial and personal data of payment cards.

A PCI-compliant firewall has been configured following PCI policies to allow specific network traffic and block others from accessing card data. Some benefits of having a PCI-compliant firewall in your organization include:

  • Builds customer trust

Any business that stores, processes, accepts, or transmits credit card information must have a reliable cybersecurity solution to gain customers’ trust. Users want reassurance that their data is safely stored and transmitted in your organization’s network, backed by the strictest information security policy.

By showing that your business meets international standards for card information security, you can easily build customer trust and increase patronage.

  • Prevents data breaches

The primary benefit of PCI DSS compliance is that it eliminates the risks of data breaches. Data breaches can lead to huge financial losses and even damage a company’s reputation. Often, hackers look for easy targets, and one quick way to find them is by checking for companies whose firewall configuration isn’t PCI-compliant.

Being PCI-compliant shows any potential attacker that your network security is top-notch, thus discouraging them from taking any further action. It displays that your cardholder data environment is protected by formidable security solutions that meet industry regulations and best practices.

  • Helps you to meet global standards

PCI DSS compliance was put together by the PCI Security Standards Council (PCI SSC). The body was formed by Visa, MasterCard, Discover, American Express, and JCB– the top five payment card firms.

They designed this payment card information security policy to prevent data breaches and protect network system components, including servers, firewalls, etc. Building a PCI-compliant firewall confirms that your business aligns with the most trusted payment firms and meets global cybersecurity standards for payment cards.

  • Prevents fines and penalties

Besides the financial loss that hackers directly cause from data breaches, companies may also suffer heavy fines and penalties. They may be required to foot card replacement bills, audit fees, investigation costs, and even compensate for customers’ losses.

Every business that processes, stores, accepts, or transmits payment card data must meet the ideal security standards required to avoid fines and penalties. More importantly, becoming compliant helps you establish a good reputation for your business online and offline.

  • Puts security first

A compliant firewall enjoys round-the-clock security as it is fully configured to regulate physical access and network-based attacks. So even if there’s an internal malicious actor, you can still secure your customers and prevent unauthorized access.

This attitude of putting security first across your IT infrastructure can save you from losses worth hundreds of thousands of dollars in the long run.

  • Maximum speed functionality

Organizations that deploy industry-standard firewall policies can function at maximum speed as they’re assured they have a secure network. Working at full speed enables goods or service providers to generate greater revenue as they can satisfy more customers within a short time.

Plus, PCI firewall rules don’t only protect the Cardholder Data Environment against attacks, but they also improve your system’s operational efficiency. As a result, you generate maximum ROI from your investment.

What are the benefits of a PCI-compliant firewall?

As a business handling, storing, processing, or transmitting payment card data, it’s essential to prioritize building trust and a positive reputation. This is because customers prefer to do business with brands they trust to provide top security for their card information.

Unarguably, being PCI-compliant is one of the core ways to show customers and partners that your business can be trusted. It makes them understand that your security posture meets international standards and can withstand tough security threats.

Also, with your compliance certification, you gain a competitive advantage over many other businesses as statistics show that only about 36% of businesses are PCI-compliant. Being compliant allows you to compete with top brands by displaying the alignment of your card data security with the best industry practices.

More interestingly, PCI compliance allows every component of your network environment to function optimally, thus giving an impressive and satisfactory output.

How does PCI compliance affect my business?

PCI DSS firewall should be configured in line with standard practices to protect Cardholder Data Environments (CDE) effectively. You must first regulate the flow of traffic to gain more control and create an effective risk management strategy that prevents cybercriminals from impacting your network.

Organizations with a highly complex CDE may resort to segmentation using multiple firewalls, which involves separating systems for better control.

Here’s how the PCI DSS firewall should be configured:


Set security: Every switch port should have security settings, especially when following segmentation practices. You must set firewalls at the CDE boundaries and also between untrusted networks and the demilitarized zone (DMZ). The DMZ is a sub-network providing an extra layer of security to your internal private network.


Establish rules: Set and regularly update firewall rules so that systems and system ports are only accessed by authorized sources. All wireless networks should have perimeter firewalls installed to prevent access from outside the defined environment. Outdated software programs and default passwords should also be avoided during configuration.


Inbound/outbound rules: Determine what traffic should be allowed to enter or exit your network based on business needs. Firewalls should only allow traffic needed in the CDE, while other unnecessary traffic must be blocked. Also, direct traffic from the CDE to the Internet should be blocked to avoid creating a loophole.


Use VPNs: remote users accessing the system should do so via virtual private networks (VPNs). Also, their portable devices (laptops, desktops, or smart devices) should have firewalls installed.


Add/Close switch ports: You should use switch ports (e.g., Internet, office, CDE) to segment different networks. Also, ensure that end users can’t alter the firewall’s configuration on devices and that their management procedures are well-documented.

How should the PCI DSS firewall configuration be?

Every company that aims to achieve PCI compliance must fulfill the twelve PCI DSS compliance requirements. Doing this ensures that your organization’s network enjoys top-tier security controls against any cybersecurity threat. Below are the PCI DSS requirements.


1. Install a firewall and maintain it


The first step toward becoming PCI-compliant is installing and maintaining a firewall. Proper firewall configuration will effectively block all untrusted networks attempting to penetrate your system to steal data.


Businesses must configure their firewalls, routers, and other network security devices through industry standard rules to ensure they filter inbound and outbound traffic effectively. Inbound traffic is traffic originating from outside your network and attempting to penetrate it, while outbound traffic comes from within your network and goes out.


It’s crucial to have standard inbound and outbound firewall rules to protect the network against malicious incoming traffic, such as malware, denial-of-service (DoS) attacks, etc. With firewalls, routers, and other components properly configured, your first line of defense is optimized for card data protection.


2. Initiate strong password protections


Third-party components in your IT infrastructure, such as servers, network devices, point of sale (PoS) systems, applications, access points, etc., must be protected with strong passwords. Avoid using vendor-supplied defaults or generic passwords because they are simple and can be guessed easily.


In fact, many of them are published online, hence why changing them to stronger passwords is a requirement. You must also have a list of the devices and software that require a password or any other security feature in your network.


Plus, you should document your company’s configuration procedures from the time you obtain the third-party product until it enters your IT network. Doing this helps in vulnerability management so that you will take all required security measures each time you introduce a new component to your IT infrastructure.


 3. Protect the data of cardholders


The essence of becoming PCI-compliant is to protect cardholder data, and that’s why this third requirement is the most important of all. Companies must know the type of data they want to store, its location, and the retention period.


Knowing the type of data you want to store helps in determining the most secure way to protect it. Encryption can protect all data through industry-accepted algorithms, truncation, or tokenization. Typically, two-layer protection is considered the best, such as using both encryption and tokenization.


You must conduct regular maintenance and scanning to detect any unencrypted primary account numbers (PAN) and ensure that your PCI DSS encryption key management process is strong.


As part of the third requirement, businesses should follow standard security controls when displaying primary account numbers. Ideally, only the first six and last four digits can be displayed.


4. Encrypt data that gets transmitted

When data is transmitted across open, public networks like the Internet, WiFi, and Bluetooth, it must be encrypted. Failure to encrypt data puts it at great risk, as cybercriminals can often access such data.


However, with proper encryption, you can maintain top security for your data at rest and in transit. Also, you should know the destination and source of card data to avoid sending or receiving data from untrusted networks.


5. Install and maintain anti-virus software

Companies must install and maintain anti-virus software to protect against malware that can impact system performance. All systems and devices (e.g., laptops, desktops, mobile devices, workstations, etc.) providing local and remote IT network access should have anti-virus programs installed on them.


These devices are commonly affected by malware which disrupts system functionality and allows unauthorized access to your network. Nonetheless, with an active and up-to-date anti-virus or anti-malware program, you can detect known malware, protect your system from malicious actors, and have more access control.


6. Update your systems and software

The next layer of requirement is the update and maintenance of systems and applications. You should define and implement a process that identifies security risks from anti-virus programs to firewalls.


This process should deploy a reliable third-party source to classify these security risks and send notifications for any newly discovered vulnerabilities in the PCI DSS environment. To ensure effective vulnerability management, you should patch (update) all systems, especially those that store or interact with the cardholder data.


Examples of other systems that should be patched regularly include routers, application software, switches, databases, and POS terminals. Timely patching helps you resolve any vulnerabilities or bugs (errors) in your system before bad actors take advantage of them.


7. Restrict access to data


Access control is a huge criterion when it comes to achieving PCI compliance. Employees should only have access to the data required to fulfill their roles and meet business needs. In other words, access to card data and systems should strictly be on a need-to-know basis.


All staff who do not need cardholder data to execute their roles should be restricted from accessing it to prevent unnecessary exposure of sensitive data. Also, you must have a comprehensive list of all staff who need card data and their roles. Other details to document include:


role definition


current privilege level


expected privilege level


data resources required by each user to execute operations on card data.


8. Establish unique IDs for those with access


After determining users who need access to cardholder data, you’re required to establish unique IDs for each of them. Some organizations use shared/group passwords for staff, which makes it challenging to track certain activities.


Such organizations must switch to having unique IDs for each authorized user to fulfill the eighth requirement for PCI DSS compliance. A two-layer authentication must be implemented for every non-console administrative access (remote access).


Establishing a complex and unique ID for each person with access to card data allows you to trace any unusual activity to their respective users. Thus, every user can take responsibility for their actions and be summoned for accountability or even face the necessary disciplinary actions for their security errors.


If there’s a security threat, unique IDs enable swift response before serious damage is done.


9. Physical access needs to be limited


Physical access to systems with cardholder data must be restricted to prevent data theft, manipulation, or destruction. The systems must be locked in a secure location (in a room, drawer, or cabinet).


You should monitor the entry and exit doors of physical locations like data centers using surveillance cameras or electronic access controls. All physical access to systems with cardholder data must be kept in a log and retained for at least 90 days.


Companies should allow only authorized visitors in the area and keep a document of their activities. Whenever an employee is switching roles or during resignation, all company-related systems with cardholder data or access to your internal network should be retrieved.


Finally, on the restriction of physical access, you must destroy any media or device that’s no longer needed in your system.


10. Establish and maintain access logs


One very common non-compliance challenge is the establishment and maintenance of access logs. Organizations must have a proper record-keeping and documentation process for all activities across their network, including data flow and access frequency.


The collected information about access logs and other activities should be reviewed daily to detect and address any irregular actions. This requirement mandates that the collected information must meet the standard and be taken in real-time to enhance the audit phase.


11. Scan and perform tests to identify vulnerabilities


Hackers understand that every system has a degree of vulnerability, and that’s why they tirelessly try new methods to help them penetrate networks and steal data. However, with frequent vulnerability scans and penetration testing, you can stay on top of cyber threats and keep users’ payment card details safe at all times.


Vulnerability scans can help you discover any possible error in software programs and your entire security system. With penetration testing, you can discover your IT infrastructure’s weaknesses using the same tools and techniques as hackers.


As a result, you will be able to block any loopholes in your physical and wireless networks before cybercriminals detect them.


12. Document your policies


The last requirement for PCI DSS compliance relates to the documentation of information security policies. The policies must be reviewed annually and forwarded to the right persons (such as employees, vendors, etc.) to tackle evolving cyber threats effectively.


Some important information to include during documentation includes your inventory of equipment, the process of information flow and storage, software, employees with access to sensitive data, etc. As part of fulfilling the last requirement, you must:


Perform a formal risk assessment to determine critical assets, threats, and vulnerabilities.


Conduct user awareness training


Run employee background checks


Perform incident management

Twelve requirements to become PCI-compliant?

Achieving PCI DSS compliance is one big step toward success for any business storing, processing, accepting, or transmitting payment card information. The process is often daunting and time-consuming as companies must meet the twelve compliance requirements to get their certification.

Firewall configuration alone, which is the first requirement, requires keeping thousands of rules in mind. It’s one of the most challenging requirements on the path to PCI DSS Compliance, especially since the rule bases frequently change.

Also, even after receiving compliance certification, businesses must show that their security systems continuously align with the industry’s regulations and standards through consistent auditing.

All this work can be quite tedious for companies, making it challenging to achieve or maintain PCI DSS compliance. Now, that’s where AlgoSec comes in.

AlgoSec helps you with PCI DSS compliance by preparing your firewalls with the proper configuration that’ll help you be compliant and fulfill the first requirement easily. From installation to maintenance, we’d assist you in setting up a compliant firewall that provides formidable security for the cardholder data environment.

At AlgoSec, we understand the PCI DSS firewall requirements to achieve a compliant firewall and have the right tools and solutions to configure your firewall.

Furthermore, we’d help you consistently stay compliant by identifying gaps in compliance and enabling you to remediate them. By leveraging our intelligent automation solution, you can avoid costly errors caused by manual work, thus helping you stay compliant and secure when adding, removing, or changing policy rules.

We know the challenges most companies face when attaining PCI DSS compliance. That’s why we have created an effective solution that enables flawless data collection and auditing, thus helping you establish and maintain access logs as well as document your policies effortlessly.

Lastly, we help your business stay continuously compliant by simplifying firewall audits. This allows you to quickly detect any loopholes and regularly update your firewall rules to avoid violating any policy.

How AlgoSec helps with PCI DSS compliance

What is a firewall PCI DSS compliance?

What are the benefits of a PCI-compliant firewall?

How does PCI compliance affect my business?

How should the PCI DSS firewall configuration be?

Twelve requirements to become PCI-compliant?

How AlgoSec helps with PCI DSS compliance

Get the latest insights from the experts

Use these six best practices to simplify compliance and risk mitigation with the AlgoSec platform

Learn how AlgoSec can help you pass PCI-DSS Audits and ensure

See how this customer improved compliance readiness and risk

Choose a better way to manage your network

bottom of page