One of the main issues that inhibit the development of contextaware mobile applications is the lack of systematic methods for sensor data acquisition. This lack, however, is a result of the diversity of sensor data and its acquisition devices. In face of this, there is a need for general engineering solutions in order to address the common sensor data acquisition concerns. This paper presents a service-oriented architecture that allows the rapid prototyping of sensor data provisioning systems. This architecture is then applied to the Healthcare domain for providing cardiac signals in the scope of a context-aware telemonitoring system. The architecture is defined by entity and behavior models through a service-oriented design (SOD) language that has tool support. Categories and Subject Descriptors D.4.7 [Operating Systems]: Organization and Design- distributed systems, hierarchical design, real-time systems and embedded systems; D.2.11 [Software Engineering]: Software Architectures