What is the function of a firewall in relation to PCI DSS?

The function of a firewall in relation to PCI DSS is primarily to protect cardholder data by controlling incoming and outgoing network traffic. Firewalls act as a barrier between trusted internal networks and untrusted external networks, such as the Internet. They monitor and filter traffic based on predetermined security rules, which helps to prevent unauthorized access to sensitive data, including cardholder information.

In the context of PCI DSS, maintaining a secure network infrastructure is crucial for protecting payment card information during transmission. By implementing firewalls effectively, organizations can mitigate the risk of data breaches and ensure that only legitimate traffic is allowed to pass through to the systems where cardholder data is processed or stored.

The other options, while related to network security and data management, do not accurately describe the primary role of a firewall in the context of PCI DSS. For example, analyzing user behavior is more aligned with intrusion detection and prevention systems rather than firewalls. Storing sensitive data securely is related to data encryption and database security practices. Lastly, providing wireless connectivity is not a function of a firewall; rather, it pertains to networking equipment and services.