When examining firewall and router configurations, inbound internet traffic should be limited to which of the following?

Limiting inbound internet traffic to IP addresses within the DMZ (Demilitarized Zone) is a critical practice in network security, particularly in compliance with PCI DSS standards. The DMZ is a subnetwork that exposes external-facing services to the internet while providing a layer of protection to the internal network. By configuring firewalls and routers to restrict inbound traffic to only those IP addresses that are designated for the DMZ, organizations can effectively minimize exposure and reduce the risk of unauthorized access.

The DMZ serves as an intermediary zone between the internet and the internal network, allowing services like web servers or email servers to be accessible to external users without compromising the security of sensitive data or internal networks. This approach controls what external entities can communicate with, thereby limiting the surface area for potential attacks.

In the context of security best practices, allowing all public IP addresses or any IP address that requests access would greatly increase vulnerability, making it easier for malicious actors to exploit services. Similarly, restricting access to only private IP addresses would not be feasible, as those addresses are not routable on the internet and thus wouldn't be relevant for inbound traffic from external sources. Hence, focusing on the DMZ for inbound traffic aligns with the principle of minimizing potential threats and enhancing the overall