According to PCI DSS requirement 1.2, firewall and router configurations must restrict connections between which two entities?

The requirement described is focused on the protection of cardholder data within the context of the Payment Card Industry Data Security Standard (PCI DSS). One of the critical aspects of creating and maintaining a secure environment involves establishing strict controls around where and how cardholder data can be accessed.

In this case, option B correctly identifies the need to restrict connections between corporate networks and the cardholder data environment. The rationale for this specific requirement is to mitigate the risks associated with unauthorized access to cardholder data. By limiting the communication pathways between these two environments, organizations can significantly reduce the potential attack surface that cybercriminals may exploit.

The cardholder data environment (CDE) contains sensitive information such as credit card numbers and personal data. Thus, it is imperative that access to this environment be controlled tightly to prevent data breaches or leakage.

Other choices do not capture the specific focus on safeguarding the cardholder data environment as required by PCI DSS. While connections between the internet and corporate networks, or external vendors and corporate networks, are important considerations for overall network security, the primary emphasis of PCI DSS requirement 1.2 is on protecting the cardholder data environment itself from the corporate network, ensuring that only authorized and necessary connections are allowed.