TOWARDS ENVIRONMENTAL PROCESS SHARING FOR GEOSS

Transcription

1 TOWARDS ENVIRONMENTAL PROCESS SHARING FOR GEOSS Lorenzino VACCARI, Mattia SANTORO, Max CRAGLIA, Lorenzo BIGAGLI, Michele CHINOSI, Stefano NATIVI EuroGEOSS Conference Madrid January 2012

2 Summary Motivation Process design Gap Analysis Business Process Modelling Notation Broker for Service Composition The CaaS Approach CaaS vs. Workflow Engine 2

3 Motivation One of the major challenges for multi-disciplinary interoperability is environmental model sharing and composition In the GEOSS context, such models should be designed as business processes composed of (web)services In the GEOSS framework the majority of registered services exist as independent components Currently, a manual and static composition of a number of predefined geo-services has to be performed The automatic composition of registered services is still an open issue 3

4 Business Process Design - Gap Analysis There exist several gaps which must be filled by a Business Process Design Standard Actors definition Action steps Alternatives paths and flows Steps definition granularity Parameters and attributes specification Use of Formalized languages Pre- and post- conditions 4

5 Modelling Business Processes Business process design at three levels of abstraction: Abstract Business Processes specification high level of abstraction Intermediate Business Processes The business processes are not still executable but can be simulated to test their validity and completeness Executable Business Processes makes it possible to execute concrete business process (workflow) specifications by using workflow execution engines 5

6 The Business Process Modeling Notation (BPMN) Provides a notation that is readily understandable by the stakeholders of different disciplines Creates a standardized bridge for the gap between the business process design and process implementation Can be serialized into XML languages designed for the execution of business processes, such as BPEL and XPDL, to executing and sharing the workflows between different stakeholders 6

7 BPMN products comparison Metrics LICENCE PLATFORMS independent solutions BPMN 2.0 compatibility BPEL/WSDL compatibility XPDL output SIMULATION and VALIDATION REPOSITORY and COLLABORATION EASE TO USE and GUI Comparative analysis: 20 software packages Selected (JRC): TIBCO Business Studio 7

8 Main Objects 8

9 Forest map workflow 9

10 .described in BPMN (extract) JRC RSDI Initiative (Michele Chinosi, Nicole Ostlaender) BPMN is a standard and has a precise semantic It is possible to transform the diagram into an XML representation for the workflow execution of the process and its exchange with other scientists 10

11 Broker for Service Composition A Service Composition Broker A new component was developed within the UncertWeb FP7 Project CaaS: Composition as a Service BPMN description of the Business Processes Workflow Execution Engine: accepts BPMN 2.0 workflows 11

12 The CaaS design rationale Mediation-based architecture (Brokered-SOA) System-of-Systems approach Ease of integration with the Global Earth Observation System of Systems (GEOSS) Common Infrastructure (GCI) Ease of integration with the W3C Web Services technologies 12

13 The CaaS Approach 13

14 Preprocessing steps 1. Components Validation 2. Components compatibility check 1. Mismatches identification 2. Mismatches resolving (through mediation/adaptation approach) 3. Identification of actual I/O parameters of the Executable BP

15 ehabitat BPMN

16 Executable ehabitat BPMN

17 CaaS and Workflow Engine are complementary CaaS addresses existing challenges not covered by WF technology CaaS Workflow Engine Mediation Distribution Technological independence Loosely-coupled High Low Transparent parameter mismatch resolving Flexibility High Low User Entry-Barrier Low High

18 CaaS benefits No need of a composition infrastructure Alleviation from the technicalities of workflow definitions (type matching, identification of external services endpoints, binding issues, etc.) User can focus on his/her intended target User may submit incomplete workflow definition, and leverage CaaS recommendations (that may derive from an aggregated knowledge base of user feedback) to execute it Of particular interest for multidisciplinary scientific contexts, where different communities may benefit of each other knowledge through model chaining

19 CaaS, EuroGEOSS and next steps Collection and the analysis of the models proposed by each EuroGEOSS thematic areas (Forest, Biodiversity and Drought) Assessment of the CaaS solution proposed by the UncertWeb Project Investigation on how geo-processing and service chaining technologies can be improved regarding performance and reliability 19

20 Thank you for your attention!