<p>The trend of heterogeneous servers and the rise of Software-Defined Data Center (SDDC) have transformed data center management. Collaborative management of hardware and software is crucial for rapid deployment and migration. As the boundary between physical infrastructure and virtual infrastructure blurs, data center management faces challenges in fine-grained resource provisioning, energy efficiency optimization, and security assurance. To address these challenges, this paper proposes a novel Software-Defined Platform Management (SDPM) architecture based on out-of-band management. This architecture extends server platform management capabilities from physical infrastructure to virtual machines. By abstracting heterogeneous resources into execution points managed by a centralized control plane and consolidating standard industry interfaces, the architecture introduces capabilities for resource provisioning, energy consumption regulation, as well as access control and trusted computing support. A prototype implementation on a real server and experimental results demonstrate that the architecture can dynamically allocate resources based on predictions of virtual machine workloads, optimize energy consumption through workload-aware and temperature-driven fan control, and support secure communication channels to implement advanced access control policies. These results highlight SDPM’s potential in advancing resource provisioning, energy efficiency, and security in modern data centers.</p>