According to PCI DSS requirement 1, Firewall and router rule sets need to be reviewed every ________ months.

The correct answer is associated with the PCI DSS requirement that specifies the frequency at which firewall and router rule sets must be reviewed. According to the PCI DSS, organizations are required to conduct a review of firewall and router configurations at least every six months. This regular review helps ensure that the security measures in place remain effective, are up to date, and that any changes in the network environment are reflected in the security rules governing access to cardholder data.

Having this six-month review period supports the principle of continuous security vigilance, helping organizations to adapt to new threats or changes in network architecture and preventing unauthorized access to sensitive data. Thus, adhering to this timeframe is essential for compliance and for maintaining a strong security posture.