A Data Dependency Relationship Directed Graph and Block Structures Based Abstract Geospatial Information Service Chain Model

With the development of Web services and service-oriented architecture (SOA), Web services has become the primary method to implement geospatial information sharing and interoperability, besides, geospatial information processing modeling basing on Web service compositions is one of the research hotspots. The data-centered procedure of geospatial information processing describes the steps of data processing and information retrieval. Current Web service composition languages and workflow models no matter low-level IT-oriented or high-level abstract are all with complex models, can not express data and data flow intuitively and not suit for geospatial domain users. In this paper, a data-dependency directed graph and block structures based abstract geospatial information service chain model (DDBASCM) is proposed and the translation method to BPEL is also suggested, geospatial domain users who are not Web services experts can modeling service chains intuitively, translate service chain into BPEL executable process and execute it using BPEL engine.