The present paper presents a Cyber Physical Power System (CPPS) framework based on the Service-Oriented Architecture for proactive transmission grids control, modeling and monitoring. CPPS paradigm aims at integrating and coordinating computation, networking, and physical processes according to a holistic vision of the transmission system. The key feature of the proposed framework is the ability of multiple entities to process, manage and share massive heterogeneous information. More specifically, the idea is to conceptualize a holistic architecture that enables the computing resources to deliver much more automation that the sum of its individually self-managed components, allowing the Transmission System Operator to improve the interoperability and the integration level of monolithic and hard to customize power system control and monitoring functions. Moreover, it allows TSO to develop content-based data extraction and aggregation from a host of pervasive sensors network and to exploit distributed embedded computing resources aimed at solving large-scale problems. To assess the benefits of the CPPS framework, the first experimental results obtained on a real test bed are presented and discussed.