This Service Guide contains technical details on the Monitor, Measurement Server and Measurement Server Extensions. The purpose of this book is to provide a technical foundation for the monitoring system in order to support effective troubleshooting and repair. The book is not intended to be a comprehensive, in-depth explanation of the product architecture or technical implementation. Rather, it is developed to offer enough information on the functions and operations of the monitoring systems so that engineers who repair them are better able to understand how they work. It covers the physiological measurements that the products are designed to provide, the Measurement Server that acquires those measurements, and the monitoring system that displays them.