The Policy Compute Engine (PCE) is a centralized component within Illumio's microsegmentation solution that functions as the decision-making system for security policy management. The PCE observes, analyzes, and calculates security policies based on real-time context including application dependencies, user behavior, network traffic patterns, and workload attributes. The system automatically maps communication flows between applications, services, and workloads to provide visibility into east-west traffic and interdependencies. It uses metadata such as workload role, environment type, and labels to compute intent-based policies rather than relying solely on IP addresses or ports. The PCE enables policy simulation and modeling before enforcement, allowing security teams to test strategies without disrupting operations. Once policies are calculated, they are distributed to enforcement points across data centers, public clouds, containers, and endpoints. Policies are enforced at the host level through the Illumio VEN (Virtual Enforcement Node) without requiring traditional firewalls or network infrastructure changes. The system provides centralized visibility and control through a single management interface for segmentation across hybrid and multi-cloud environments. It supports compliance requirements, breach containment, and operational efficiency by automating policy creation and management while enforcing least-privilege access controls.