# Performance and Challenges of Service-Oriented Architecture for Wireless Sensor Networks
## 7 Service-Oriented Architectures Approaches for WSNs
### Other Approaches  
Recently, SOA has gained a lot of attention for providing flexibility in the designing of WSN applications. In [73], a method of service selection with flexible Service-Oriented Network Architecture (FSONA) addresses the issues of WSNs. These issues are increasing because of the lack of interoperability and the addition of new services or adaptation new protocols between the sensors and communication architecture. Addressing these issues provides a general communication between users, developers, and applications. In this architecture, a common platform connects the heterogeneous and homogeneous services [79]. Most of the existing routing protocol studies exploit SOA in WSNs. In [80], the path vacant ratio is used to find a group of disjointed paths from available ones and link them. The load balance and congestion control algorithms are used to check and control the load on multipath. The Threshold Sharing Algorithm (TSA) has the ability to divide each packet into many segments before transmitting it to the destination over the multipath based on path vacant ratio [80]. A secure and adaptive load-balancing multipath routing protocol based on AODV called Service-Oriented Multipath AODV [80]. The benefit of applying AODV protocol is to extend the load balance algorithm due to its routing protocol efficiency, without generating any congestion. SM-AODV provides secure data transmission and improves data confidentiality in Service-Oriented WSNs [80]. The features of multipath routing protocol include a secure transmission of data, independent applications, adaptive congestion control, and extensibility [80]. Another Service-Oriented approach supports QoS and real-time in Industrial Systems [81]. The SOA philosophies can be applied in the enterprise IT and the sensor network itself [81]. The enterprise IT system integrates into the sensor nodes by linking the Service Descriptions (SD). The linked data of the SD and RDF (Resource Description Format) addresses the problem generated through integrated enterprise IT system with sensor nodes [81]. The sensor notes interact with different service descriptions connected to other service descriptions by the Unified Service Description Language (USDL) method. The corresponding interfaces and the service description are located on/off the sensor or on both, which can lower cost reducing data on the sensor [82]. The flexible architecture is introduced in [83] for sensor networks based on web services and web mashup [83]. Web services build based on SOA. The data is provided through sensor nodes, and service is provided through WSNs for client applications and provided services, such as sensor nodes, to generate raw data. The raw data is processed and generated by different analyses, filters, complex processes, and web mashup, which provides value-added services. This architecture is adaptive SOA for designing WSNs. The services consist of the abstraction that can be used for developing WSNs applications. XML is used for representation and exchanging data between applications and the network. The WSN is integrated with the mashup, which is used to build different applications on top of the virtual ecosystem of services [83]. SOAP and HTTP modules manage communications. The SOAP should be presented in web mashup and sink nodes, with HTTP module in sensor nodes [83]. Additionally, SOA is applied in business applications. The SOA and mashup have allowed the enterprise to transfer complex applications through integrating the information over internal and external sources. It enables the user to take heterogeneous data from different sources. Therefore, it provides graphical tools called \"enterprise mashup\" for business users to select, integrate, and analyze data as needed. The approach addresses the collection of accurate and real-time information to satisfy business requirements based on enterprise location and the structure of the data [84]. Moreover, there are various concrete implementations of SOA approaches.