The rule-based security policies configured on the Policy Decision Point (PDP) are designed to define rules that specify how information can flow within an organization's network. These rules are integral to implementing the principle of least privilege and ensuring that data is accessed only by authorized entities under strict conditions. By controlling information flow, the PDP helps in mitigating the risk of data breaches and unauthorized access, reinforcing the Zero Trust model's emphasis on stringent access control and continuous verification of trust.