European conference of the Czech Presidency of the Council of the EU TOWARDS eENVIRONMENT (Challenges of SEIS and SISE: Integrating Environmental Knowledge in Europe) http:/www.e-envi2009.org/proceedings/ J. Hřebíček, J. Hradec, E. Pelikán, O. Mírovský, W. Pilmmann, I.Holoubek, R. Legat (eds.) Masaryk University, 2009

SOSI Spatial Observation Services & Infrastructure G. Triebnigb, L. Kucerac, S. Meisslb, M. Novaceka, W. Weghoferd, L. Zsidaie a

ANF Data, Pujmanové 1221/4, 140 00 Prague 4, Czech Republic ([email protected])

b EOX c

IT Services, Thurngasse 8/4, 1090 Vienna, Austria ([email protected])

GISAT, Charkovská 7, 101 00 Prague 10, Czech Republic ([email protected]) d

Siemens Austria, Siemensstrasse 88-92, 1210 Vienna, Austria ([email protected])

e

Siemens Hungary, Gizella út 51-57, 1143 Budapest, Hungary ([email protected])

Abstract: SOSI is a project for development and verification of innovative infrastructure and services within the context of land monitoring and Earth observation initiatives at European and Member State levels. The information managed within SOSI includes official land cover products and satellite observation data. The project’s results contribute to the concept definition of the Shared Environmental Information System (SEIS) emphasizing symmetrical online sharing of environmental information as opposed to unidirectional environmental reporting. In a pre-operational set-up, involving the European Environment Agency (EEA), four European Member State sites, and the European Space Agency (ESA), a decentralized information system is demonstrated integrating distributed data and processing services as well as interactive geoportal access via multi-lingual graphical user interfaces to geospatial information products provided at multiple levels and content granularities. Practical and more so marketable solutions are investigated within SOSI respecting the INSPIRE directive, guidelines and implementation rules for spatial data service models, engineering and technology. The paper presents the architectural and technological approach along the five ISO/RM-ODP viewpoints and concludes with the main recommendation that service provisioning in the SEIS framework can strongly benefit from a cost and time saving (re-)utilization of the Service Support Environment (SSE) technology provided by ESA and from building upon the related rich experience. Keywords: Environment monitoring, satellite Earth observation, land cover, Service Oriented Architecture. 1.

BACKGROUND AND CONTEXT

1.1

SEIS – a European Perspective

According to the European Union’s 6th Environmental Action Programme aiming at a Sustainable Development Strategy integrated assessments of environmental information are becoming the trend. This nurtures the vision of a Shared Environmental Information System (SEIS) which’s scope is to improve, modernise, streamline, and connect environmental information systems in Europe and world-wide (see Ref. EC, 2008). From the European Environment Agency’s (EEA’s) perspective (Steenmans, 2009) SEIS is about: Sharing (organisation): Political commitment (legislation); Partnership (win-win); Networking (connecting);

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Environmental Information (content): Horizontal integration (data centres); Vertical integration (local to global); Online access - real time for policy makers and public; System (infrastructure and services): Existing ICT Infrastructure; INSPIRE, Reportnet, GMES, etc.; New e-Services (e-Government). In this list the SOSI project addresses primarily the items “networking”, “online access” and all items under “System”, i.e. Europe's infrastructure backbone for environmental services. 1.2

SOSI – Verification of Infrastructure and Services Concepts

SOSI is a development of innovative “Spatial Observation Services and Infrastructure” within the context of Land Cover (LC) monitoring and Earth Observation (EO) initiatives at European and Member State (MS) levels. The project is motivated by the need of verification of today’s SEIS infrastructure and services concepts (see Section 1.1). The project’s objective is to demonstrate distributed data and processing services as well as decentralized access at multiple levels, languages and content granularities. SOSI is a: Project (time/resources limited) contracted by the European Space Agency (ESA); Service-Oriented Architecture (SOA) concept; Demonstrator system (operated over a limited time period); Concept verification activity performed jointly with EEA, MS, and ESA. The verification results and related recommendations are the most important SOSI project deliverables. 1.3

Coherence with INSPIRE, GEOSS, and GMES Architectures

A key goal of the SOSI project is to ensure coherence with architectures dealt with by the programmes, projects, and standards initiatives given in Table 1. Table 1. Sources of Standards Requirements for SOSI. Programme/Project INSPIRE

GEOSS GMES - HMA OGC GIGAS ISO/TC 211 CEN/TC 287 LMCS/Geoland

Explanation (Relevance for SOSI) Directive 2007/2/EC of the European Parliament and Council establishing the Infrastructure for Spatial Information in the European Community. Normative implementing rules and informative guidance documents on the aspects of metadata, interoperability, network services, data and service sharing are or will be adopted. Global Earth Observation System of Systems, intergovernmental programme; core architecture in alignment with OpenGIS Consortium (metadata/catalogue) standards. European Global Monitoring for Environment and Security initiative; including Harmonised Access to heterogeneous EO satellite Missions. OpenGIS Consortium leading the development of standards for geospatial and location based services. Support Action to the European Commission (EC) for identification and definition of needs to enable a full integration of INSPIRE, GMES, and GEOSS architectures. Technical Committee under the International Organization for Standardization responsible for digital geographic information; issues International Standards, Technical Specifications and Technical Reports (encoding, metadata, services, etc.). TC under the Comité Européen de Normalisation for digital geographic information in Europe; close cooperation with ISO/TC 211 to avoid duplication. GMES Land Monitoring Core Service, development of value-adding (mapping and information) services in the EC Framework Programme 7 project geoland2.

In spite of the complexity and dynamics of the listed programmes and projects the SOSI project can build upon the latest status and specifications through formal involvements of SOSI project team members within OGC, HMA/DAIL, GIGAS, and geoland2. 1.4

Service Support Environment (SSE)

SOSI utilizes the Service Support Environment (SSE) (ESA, 2008) which is a freely available overarching infrastructure permanently hosted and operated by ESA that facilitates the set up of operational services for EO. Currently more than 290 services are

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connected to SSE serving over 1700 registered professional & science users. SSE is beneficial for Service Providers (SPs): Allowing SPs to fully control their own infrastructure; Reducing service set-up/demo costs and time to market; Allowing an easy re-use of generic or basic services; Allowing SPs to concentrate on their own specific skills and added value; Combining and chaining service elements within the supply chain; Enabling the cooperation between SPs, etc. 1.5

Demonstration System

The SOSI Demonstration System under implementation is shown in Figure 1. Four servers hosting MS-level services are installed in Austria, Czech Republic, Hungary, and Luxembourg. A European-level service is provided by the EEA. The SSE hosted at ESA provides the geoportal, workflow, and registry functionality. The services and their characteristics are further explained in Chapter 4. They are “consumed” by various users on the Internet utilizing different kinds of clients.

Deployment of SOSI Demonstration System

LC Server European Environment Agency

LC Server Luxembourg

EO .. Earth Observation Products LC .. Land Cover Products

EO + LC Server MERIS Archive Classification Engine Czech Republic LC Server Austria

Internet LC Server Hungary

Users

Web Browser Terminals

Other Geoportal Servers

(Decision Support) Applications

Geoportal Server Workflow Engine Registry Server European Space Agency

Figure 1. SOSI Servers in Member States and at European Agencies. 1.6

SOSI Architecture Viewpoints

The Reference Model of Open Distributed Processing (RM-ODP, ISO/IEC 10746-1,2,3,4) is an architecting standard. The model is widely adopted as best practice approach by the geospatial data system engineers. Presentations of the five RM-ODP design viewpoints, tailored to SOSI, are the subjects of the following Chapters. 2.

ENTERPRISE VIEWPOINT

2.1

From Reporting to Sharing

The SOSI design concept is driven by SEIS principles (Steenmans, 2009) that data and information shall be:

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Managed as close as possible to its source; Collected once and shared with others for many purposes; Readily available to public authorities to easily fulfil reporting obligations; Accessible to enable end-users to make comparisons at appropriate geographic scale; Available to the general public after due consideration of the appropriate level of aggregation, given possible confidentiality constraints, and at national level in the national language(s). 2.2

Eionet and Evolution of Reportnet

SOSI receives design guidelines and standards (e.g. the GEMET Thesaurus) established by EEA and within Eionet which is a partnership network of EEA and its member and cooperating countries involving approximately 900 experts and more than 300 national institutions. The network supports the collection and organization of data and the development and dissemination of information concerning Europe’s environment. The SOSI implementation is targeted to be linked with Reportnet which is Eionet’s infrastructure for supporting and improving data and information flows. Reportnet is based on a set of inter-related tools and processes which all build on the active use of the World Wide Web. SOSI is specifically associated with the objectives and functionalities of the EEA Land Use site which offers live maps and EEA data centre services under the address http://www.eea.europa.eu/themes/landuse. It is required, for example, that SOSI network services can be accessed via the existing EEA Land Use site. 2.3

GMES Fast Track Service on Land Monitoring

Essential innovative functionality is provided by SOSI for orchestration of network services within workflows. Product generation chains which, in the past, transferred data between processing nodes on offline physical media shall be demonstrated in SOSI to be handled, in the future, via online management and data dissemination procedures. The GMES Fast Track Service on Land Monitoring which was implemented by EEA, EC and ESA is considered as template for a SOSI demonstration example. It delivered the following products: 1. Ortho-rectified satellite images for the reference year 2006 (+/- 1 year); 2. European mosaic based on ortho-rectified satellite imagery (IMAGE2006); 3. Corine Land Cover changes 2000-2006; 4. Corine Land Cover map 2006 (CLC2006); 5. High resolution core Land Cover data for built-up areas, including degree of soil sealing, 2006; 6. High resolution core Land Cover data for forest areas 2006. For the CLC2006 and high resolution built-up areas products open access is granted and free dissemination data policy is applied. The related requirements established for the SOSI Demonstration System are to: Mimic the current geoportal access to CLC2000, CLC2006 and built-up area products keeping the products close to their geographically distributed generation services, i.e. not, as currently done in a centralized product repository; Demonstrate a processing chain fully managed as an online workflow spanning these distributed product generation services. 2.4

Specific Requirements in Member States

The requirement for the SOSI processing workflow demonstration described in section 2.3 is instantiated as a semi-automated land cover product generation chain sourced by an Envisat MERIS satellite EO product archive in the Czech Republic. As prerequisite for this

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demonstration implementation a user service facility is implemented at the MERIS archive supporting data discovery and downloading services. A case study focusing on benchmarking of MEEO Soil Mapper classification solution is another SOSI activity run in the Czech Republic. Beside the Czech MERIS EO services a national Czech SOSI LC geoportal is to be implemented. Except for the European LC datasets described above it will also include selected national GMES LC datasets and samples of low resolution LC products based on MERIS imagery. A SOSI geoportal for LC data access is also set-up in Hungary which has to support a Hungarian national language user interface. 3.

INFORMATION VIEWPOINT

3.1

Metadata Models

Service and Collection Metadata are used in SOSI to provide the details for machine-tomachine communication (operations, coupling of operations) but also contain descriptive information targeted at human readers (identifying properties of the described data or services). These metadata are in XML format, their standard references are: ISO 19115, ISO 19119, and OASIS UDDI v2 Metadata. EO Product Metadata are specified in XML format and based on Geography Markup Language (GML) Encoding Specification, OGC 03-105 and 02-069 (ISO 19136), and GML 3.1.1 Application Schema for EO Products, OGC 06-080. 3.2

Spatial Data Sets

Various delivery formats are expected by the community (e.g. GeoTIFF, JPEG2000, HDF). Conceptually (as in SSE and HMA), spatial data sets addressed in SOSI can be classified: With respect to production mechanism as Stream (regularly disseminated with predefined frequency, with given time window and given area); Cumulative (disseminated at package completion); Standalone (one-off dissemination after single request); With respect to triggering as Pre-defined Data Sets (well defined user needs/area defined in advance); or On-demand Data Sets (specification that cannot be identified in advance, e.g. emergency monitoring). The SOSI Demonstrator implements the above cases Standalone, Pre-defined, and Ondemand Data Sets when providing access to the following spatial data sets: GMES Fast Track high resolution core land cover data for built-up areas, including degree of soil sealing 2006; European-level seamless and MS-level products; updates are foreseen generated from 2009 source EO data acquisitions; Corine Land Cover - CLC2000 and CLC2006, and specific national LC products; Envisat MERIS data and derived LC Products (currently under specification). 4.

SERVICE VIEWPOINT

The informative documents “INSPIRE Technical Architecture Overview” (JRC, 2007) and “INSPIRE Network Services Architecture V3.0” (JRC, 2008) are key references for the SOSI service design. The SOSI architecture (conceptual and Demonstrator System) includes the services listed in Table 2. The SOSI Service Metamodel is shown in Figure 2. Indications are given about which service is to be supported by SSE Technology – see Chapter 6. Transactional functions for ingesting the metadata, spatial data sets, and register data into the indicated data sources are considered to be parts of the inherent data base management functions, though a use of network services could be considered (e.g. based on OGC WFS-T or WCS-T technology).

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Table 2. SOSI Services. GEOSS Taxonomy Geographic human interaction services

Geographic model/ information management services

Geographic processing services – spatial Geographic processing services – thematic Geographic system management services Geographic processing services – temporal Geographic processing services – metadata Geographic communication services

SOSI Services (INSPIRE service naming used, as applicable) SOSI geoportals based on the SSE graphical user interface SOSI spatial data discovery service SOSI spatial data view services SOSI spatial data download services SOSI invoke spatial data services (value adding service chains): For MERIS satellite data spatial and thematic processing For LC statistics processing (Built-up areas aggregated according to Corine classes) MERIS satellite data ortho-rectification service MERIS satellite LC classification service (MEEO solutions) Built-up areas aggregated according to Corine classes (GIS service demonstration example) SOSI services discovery service SSE services registry service SSE rights management None

Figure 2. SOSI Service Metamodel. 5.

ENGINEERING VIEWPOINT

SOSI is designed as loosely-coupled system based on networked services enabling distribution through functional decomposition into objects which interact at standard interfaces. Conceptually, SOSI aims to be an open system into which additional services can be added, without need for additional software development, assuming interfaces are precisely followed. SOSI is designed scalable to cope with growing user numbers. This means that it is possible, if needed, to add additional CPUs and balance the load on multiple machines, in a way that is transparent to the SOSI application software. In the SOSI Demonstration System set-up this is demonstrated for the SOSI geoportal hosted on the computer centre facilities at ESA distributing the load of all SSE induced traffic to a number of CPUs. SOSI places no restriction on the granularity of a (Web) service that can be integrated. The grain size can range from small (e.g. a component that must be combined with others to create a complete business process), to large (for example an entire value chain).

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6.

TECHNOLOGY VIEWPOINT

SOSI is based on Service Oriented Architecture (SOA) principles. The drivers of the architecture are open standard specifications from the bodies ISO, OASIS, W3C, and OGC. Figure 3 shows the software which is used in the SOSI Demonstration System. The discovery, view, and downloading services are implemented entirely on Open Source tools implementing the shown Web server protocol standards. Open Source software is also used for back-end database management.

Figure 3. SOSI Software and Web Protocols

The SSE components which are deployed as platforms in the SOSI project are: SSE Portal Server, provides the SOSI workflow engine (ORACLE SOA Suite 10.1.2) which orchestrates distributed services; several wizards for service registration at the SSE are available; The SSE WebMapViewer forms the cartographic display of the SOSI geoportal. It provides the functionality to define Area(s) Of Interest (AOI) by end-users as input to services and for receiving portrayal and download service results (see Figure 4); The SSE Toolbox provides a wrapper from legacy services at SOSI service providers to SOAP web services. It supports synchronous and asynchronous service calls and includes a FTP server. The runtime environment provides a rich standalone test centre for services. There is also a development environment providing an Eclipse plug-in for the whole service life-cycle (i.e. development, testing, debugging, configuration control, deployment, etc.).

Figure 4. SOSI Geoportal Supporting Product & Service Discovery, Versatile Area of Interest Definition, WMS-based Viewing, and WCS-based Dowloading. 7.

CONCLUSIONS AND RECOMMENDATIONS

In the search for suitable approaches to modernise and simplify the collection, sharing and use of the data and information required for the design and implementation of environmental policy in Europe, the SOSI project is contributing technical concepts for strategically important land cover (LC) services and infrastructure components. The full

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demonstrations of SOSI LC service functionalities will be available in June 2009, the Earth Observation service and LC generation service chaining demonstrations will be ready for verification towards the end of 2009. The conceptual designs of SOSI and first prototypical system implementations are, however, available and the following conclusions and recommendation can therefore be made. SSE, which is based on substantial experience with numerous operational services and users, should be considered as a valid and capable technological platform by those who need to implement services in the SEIS framework quickly, cost-efficiently and based on latest knowledge. A wide range of international architecture and technology standards is already pre-digested in the SSE tool suite helping service providers and their engineers to get up quickly on the learning curve. From the SOSI perspective the following enhancements of SSE are required: A federated user management and security layer needs to be implemented in the SSE Portal Server (e.g. in the service registration wizards) as well as in the SSE Toolbox; In order to achieve further INSPIRE conformity the SSE WebMapViewer needs upgrading with respect to SOAP binding for OGC Web services (currently only KeyValue-Pair binding supported); A modernization of WebMapViewer map interface needs to incorporate latest technologies such as AJAX. Also required are enhancements of client functionality for optimum exploitation of INSPIRE Network Services (e.g. automated bridging process from view to download). It is recommended to further study, and potentially adapt and deploy the SOSI service chaining mechanism for the next planned Europe-wide LC product generation based on 2009 EO data. An implementation of a fully online work flow appears to be feasible. Aligned with the SOSI approach, EEA and ESA should consider a ramping up of activities towards conducting an official OGC Pilot, inviting a larger community of MS representatives and user organisations into a collaborative effort that applies open standards for interoperability to achieve user objectives in a surrounding which is representative for operational use. With SOSI results at hand further consensus on architectures for geospatial information systems should be aimed at and carried forward into sustained operations. ACKNOWLEDGMENTS The project is conducted under contract of the European Space Agency ESA (ESRIN Contr. No. 21776/08/IL-G and ESTEC PECS Arrangements with CZ and H) and the strong in-kind steering support by the European Environment Agency EEA. The authors wish to thank Mr. S. D’Elia and Mr. P.G. Marchetti from ESA for fostering and supporting this initiative, Mr. A. della Vecchia for the technical cooperation as well as Mr. C. Steenmans, Mrs. A. Sousa, Mr. J. Bliki, and the LUDC team from EEA for essentially having formed the project idea, and for accompanying its execution. The preparedness by the company Geoville to host the Luxembourg SOSI instantiation is very much appreciated. The contributions of the company Spacebel regarding SOA and SSE knowhow and of the company MEEO regarding automated LC generation are very valuable to the SOSI project. REFERENCES EC COM(2008) 46 final - Towards a Shared Environmental Information System (SEIS). ESA – European Space Agency, Service Support Environment, 2008, http://services.eoportal.org. JRC – Joint Research Centres, INSPIRE Technical Architecture – Overview, V1.2, 2007, http://inspire.jrc.ec.europa.eu/reports.cfm. JRC – Joint Research Centres, INSPIRE Network Services Architecture, V3.0, 2008, http://inspire.jrc.ec.europa.eu/reports.cfm. Steenmans, C., The Future of Environmental Information, presentation at workshop “Towards Shared Environmental Information in Europe: Opportunities and Challenges for Integrated Research”, Centre for Ecology & Hydrology, Wallingford, UK, 28-29 January 2009, http://www.ceh.ac.uk/SEIS/documents/EEASEISCEH.pdf.