# Dynamic Linked Data: A SPARQL Event Processing Architecture
## 6 Conclusions  
Over the last decade, research on Linked Data has focused on unlocking the potential behind sharing data on the Web scale. If on the one hand, as evidenced by the Web of Things, the lack of interoperability across platforms and application domains can be tackled through Semantic Web technologies and standards, on the other hand, such technologies are not ready for the development of distributed, dynamic, context-aware and decentralized Web applications. Furthermore, detecting and notifying about any change within the Linked Data would be a fundamental building block, as confirmed by the ICT community with standards like Linked Data Notifications and WebSub. However, for those scenarios requiring security and dealing with high frequency data changes, solutions are still missing.  
In this paper, we presented SEPA, a SPARQL Event Processing Architecture aimed at enabling the detection and communication of changes over the Web of Data by means of a content-based publish-subscribe mechanism where the W3C SPARQL 1.1 Update and Query Languages are fully supported respectively by publishers and subscribers. SEPA is built on top of the SPARQL 1.1 Protocol and introduces the SPARQL 1.1 Secure Event Protocol and the SPARQL 1.1 Subscribe Language as a means for conveying and expressing subscription requests and notifications. The SEPA Framework provides a development environment and an application design pattern that can be adopted to enhance reuse, modularization and interoperability. The framework, complemented by tools for the performance analysis, remote monitoring and control, offers developers a modular, extensible and cost-effective solution for implementing distributed, dynamic, context-aware, interoperable and secure Dynamic Linked Data applications and services.  
**Acknowledgments:** The work presented in this paper is being developed within the EU project SWAMP (Smart Water Management Platform), Project ID: 777112, Funded under: H2020-EU.2.1.1--INDUSTRIAL LEADERSHIP--Leadership in enabling and industrial technologies--Information and Communication Technologies (ICT).  
**Author Contributions:** [PERSON] is the principal investigator of SEPA. He conceived the architecture and developed the reference SEPA broker implementation and Java API. He designed and performed the experiments. [PERSON], as an industrial partner, mainly contributed presenting the most relevant application domains. He has also been involved in the definition of the structure of the paper and in its overall revision. [PERSON] contributed to the design of the architecture, in particular, regarding dependability and extensibility. He mainly contributed to the definition of the SPARQL 1.1 Subscribe language and reviewed the presented examples. He is responsible for the software distribution and integration platform and GitHub repository management and the development of the JavaScript API. [PERSON] contributed to the related work section and the overall revision of the paper. He is responsible for the implementation of the Python API and part of the subscription processing components. [PERSON] contributed to the overall revision of the paper and with the implementation of the C API. [PERSON] contributed to Sections 4.4 and 5.5 and to the final review.  
**Conflicts of Interest:** The authors declare no conflict of interest.