The syntactic and semantic interoperability is a challenge of the Wireless Sensor Networks (WSN) with smart sensors in pervasive computing environments to increase their harmonization in a wide variety of applications. This chapter contains a detailed description of interoperability in heterogeneous WSN using the IEEE 1451 standard. This work focuses on personal area networks (PAN) with smart sensors and actuators. Also, technical, syntactic, and semantic levels of interoperability based on IEEE 1451 standardization are established with common control commands. In this architecture, each node includes a Transducer Electronic Datasheets (TEDS) and intelligent functions. The authors explore different options to apply the IEEE 1451 standard using SOAP or REST Web service style in order to test a common syntactical interoperability that could be predominant in future WSNs.