=Paper=
{{Paper
|id=None
|storemode=property
|title=GENESI-DEC: a Federative E-Infrastructure for Earth Science Data Discovery, Access, and On-Demand Processing
|pdfUrl=https://ceur-ws.org/Vol-679/paper4.pdf
|volume=Vol-679
|dblpUrl=https://dblp.org/rec/conf/enviroinfo/CossuPBFSP10
}}
==GENESI-DEC: a Federative E-Infrastructure for Earth Science Data Discovery, Access, and On-Demand Processing==
https://ceur-ws.org/Vol-679/paper4.pdf
GENESI-DEC:
a federative e-infrastructure for Earth Science data
discovery, access, and on-demand processing
Roberto Cossu1, Fabrizio Pacini2, Fabrice Brito3,Luigi Fusco1, Eliana Li Santi1, and
Andrea Parrini2
1
European Space Agency, Earth Observation Science, Applications and Future
Technologies Dept, via Galilei, 00044 Frascati, Italy
2
Elsag Datamat spa, Space Business Unit, User Segment Operations - Advanced
Technologies Group, via Laurentina 760, 00143 Roma Italy
3
Terradue Srl, Via Lunati 10, 00044 Frascati, Italy
roberto.cossu@esa.int, fabrizio.pacini@elsagdatamat.com, fabrice.brito@terradue.com,
luigi.fusco@esa.int, eliana.li.santi@esa.int, andrea.parrini@elsagdatamat.com
Abstract. Digital Earth is a visionary concept for the virtual representation of
the Earth that is spatially referenced, interconnected with the world’s digital
data repositories, and encompassing all its systems and forms, including Earth
Sciences, Natural Resources Management, Environmental Monitoring system
and human society dimensions. This paper introduces the European
Commission co-funded project GENESI-DEC. GENESI-DEC will establish
open data and services access, allowing European and worldwide Digital Earth
Communities to seamlessly access, produce and share data, information,
products and knowledge. This will create a multi-dimensional, multi-temporal,
and multi-layer information facility of huge value in addressing global
challenges such as biodiversity, climate change, pollution and economic
development. GENESI-DEC evolves and enlarges the platform developed by
the predecessor GENESI-DR project by federating to and interoperating with
existing infrastructures.
Keywords: earth science, data access, data discovery, processing on-demand,
grid, data federation, interoperability, digital earth.
1 Introduction
Digital Earth is a visionary concept for the virtual representation of the Earth that is
spatially referenced, interconnected with the world’s digital data repositories, and
encompassing all its systems and forms, including Earth sciences, natural resources
management, environmental monitoring system and human society dimensions. The
deployment of such representation would significantly improve the way we collect,
analyse and communicate information on our environment, which is one of the main
challenges of the Shared Environmental Information System. This paper introduces
the European Commission co-funded project GENESI-DEC (Ground European
Network for Earth Science Interoperations – Digital Earth Community) [1]. GENESI-
DEC will establish open data and services access, allowing European and worldwide
Digital Earth Communities to seamlessly access, produce and share data, information,
products and knowledge. The objectives of GENESI-DEC are:
Enlarge infrastructure: to enlarge the existing GENESI-DR [2] infrastructures in
terms of data, resources availability and geographical extent.
Guarantee service: to provide guaranteed, reliable, easy, effective access to a
variety of data, facilities, tools and services to an ever increasing number of Digital
Earth users from all disciplines.
Harmonise federation: to harmonise operations at selected key Digital Earth
infrastructures limiting fragmentation of solutions.
Enable user collaboration: to enable multidisciplinary collaboration among Digital
Earth users as well as the creation of user-configured virtual research facilities/test-
beds.
Respond to innovation: to integrate new scientific and technological derived
paradigms in operational infrastructures in response to the latest Digital Earth
requirements.
Promote virtualisation: to stimulate, educate and support the creation of virtual
Digital Earth research communities.
In order to reach the objectives listed above, the project proposes a repetitive
approach built around a virtuous cycle of innovation. In this approach GENESI-DEC
(system, services, capabilities, etc.) will be validated against Digital Earth
Community needs for accessing and sharing Digital Earth data and resources, and
enhanced twice in the project life-cycle and as needed, based on the results of the
research activities, taking into account developments and constraints in the areas of
standardisation, technologies and policies.
Section 2 gives an overview of the GENESI-DR infrastructure and its evolution
towards GENESI-DEC. Section 3 provides details on the discovery mechanism
promoted and adopted by GENESI-DR and GENESI-DEC. Section 4 analyses and
the major research topics that will be addressed in the project. Section 5 describes the
selected Digital Earth Communities to be used for requirements gathering and system
validation. Section 6 concludes this paper by presenting the expected impacts.
2 GENESI-DEC e-infrastructure
GENESI-DEC build upon the experience gained and the infrastructure deployed in
the predecessor project GENESI-DR. The GENESI-DR project has established an
Earth Science infrastructure federating heterogeneous digital data repositories.
Through the GENESI-DR Web Portal, users can search and access resources
physically located at the DRs.
Figure 1 provides an high level overview of the GENESI-DR system. The Central
Discovery Service, hosted at the so-called Central Site, allows discovery of data
existing in heterogeneous Digital Repositories. It can be accessed by users via the
internet through a user interface, the GENESI-DR Web Portal, or by external
applications via the exposed machine-to-machine interface. The GENESI-DR Web
Portal provides data discovery capabilities and access to processing services that
make use of high performance Grid-based computing resources to allow for scaling
up computing power and storage capacity.
Figure 1 Overview of GENESI-DR
The machine to machine interface is based on OpenSearch, a collection of
technologies allowing websites and search engines to publish search results in a
standard and accessible format (see Section 3 for more details).
The goal of the GENESI-DR project has been to build an Earth Science
infrastructure aggregating heterogeneous repositories: GENESI-DEC will focus on
how to use the expertise gained and the infrastructure set up with GENESI-DR for the
benefit of scientists who need to access and process Digital Earth data. Specific user
communities (referred to as Digital Earth Communities) have been and will be
selected and specific use cases involving such communities have to be implemented
by GENESI-DEC.
GENESI-DR will evolve towards GENESI-DEC through:
Addition of new data and services: GENESI-DEC will federate new
Digital Repositories and will provide new services as needed by the
specific use cases.
Federation of existing infrastructures: some of the selected use cases need
data that reside in existing infrastructures, so GENESI-DEC will
interoperate with such infrastructures either via standard interfaces
(following and enhancing as needed the GENESI-DR approach) or via
implementation of specific gateways. Initially the following
infrastructures will be considered: EMSO; SeaDataNet/GeoSeas; CEODE
A-SDI.
Creation of community dedicated views: While GENESI-DR services are
accessible through the same user interface, the GENESI-DR Web Portal,
which is independent of the type of user, GENESI-DEC will be accessible
through several portals representative of the different communities and
will provide dedicated visualization tools (see Figure 2). GENESI-DR
provides a limited set of services, community specific and with hard-
coded workflow: GENESI-DEC will provide a larger set of services,
including generic (community-independent) and will allow users to build
services customised on the base of their specific needs, by means of
workflow customisation tools. These latter, indeed, allow creating
customised workflows made up of existing core processing services,
which could be generic or specific of different communities so
responding to multidisciplinary needs.
Figure 2 Community specific views and customized services
GENESI-DEC can be imagined as a ring where existing digital repositories
holding Earth Science data as well as external e-infrastructures holding data and
services can be integrated, to provide common and site-specific services. Research
scientists, once connected to the GENESI-DEC ring, will eventually have access to all
required data and services in a transparent and homogeneous way. The GENESI-DEC
infrastructure will evolve progressively from a first deployment of existing services
based on the most important improvements that have been identified in the final phase
of GENESI-DR to its final configuration where several data and service providers and
e-infrastructures will be federated. The main areas of improvements are: processing
services, user workspace, search capabilities.
3 GENESI-DEC discovery service
As in GENESI-DR, data discovery services in GENESI-DEC will uses
OpenSearch interfaces. OpenSearch started in a community effort built around
Amazon's A9.com and was originally intended to allow syndication of search results.
Coupled with geo-extensions, OpenSearch provides a collection of technologies that
allow publishing search results in a format suitable for syndication and aggregation
such as Atom, XML/RDF, KML, WKT, JSON among others. Opensearch represents
a way for websites and search engines to publish search results in a standard and
accessible format. OpenSearch allows for hierarchical, drill-down methods of data
discovery. Starting with the sole knowledge of the catalogue name, the GENESI-DEC
users and applications can learn the series, dataset, and services associated with Earth
Science data. OpenSearch Description Documents list search result responses for the
given website/tool. It supports multiple responses, which may be in any format.
GENESI-DEC metadata follows a DCLite4g model. Dublin Core Lightweight Profile
for Geospatial is an extension vocabulary to Dublin Core proposed by the OSGeo
Geodata Committee. Is a subset of the FGDC metadata element set, oriented towards
practical repository management issues and provides classes that represent the Dataset
Series and Dataset and their relations covering properties specific to a geographic
application - file formats for GIS data, different coordinate systems.
The proposed OpenSearch geo extensions have been formalized within the Open
Geospatial Consortium "OpenSearch Geospatial Extensions Implementation
Standard" (09-084). This document codifies the OpenSearch GeoSpatial extensions in
a form compatible with OGC specifications. Furthermore, GENESI-DEC partners are
now responsible for the editionof the OpenGIS® Catalogue Service Implementation
Specification, Version 3.0 - Part 4: OpenSearch Query Interface (10-032).
4. GENESI-DEC research activities
GENESI-DEC reasearch activities will focus on two topics, i.e. use of semantic
technologies for data discovery and workflow compositions, and security frameworks
interoperability. Details are given in the following subsections.
4.1 Semantic technologies
GENESI-DEC will analyse and further enhance access and processing capabilities by
taking into account ontology and geo-semantics.
Geo-semantics will be used in first istance to provide users with more effective and
user-friendly search capabilities, by assisting them in the management and
interpretation of (often huge amounts of) results. To this end already developed
community specific ontologies will be used.
At a later stage, semantic technologies will be used to assist users during the
definition of new processing services. In more details geo-semantic will be used to
support users in the definition of customised task workflow.
4.2 Security Frameworks Interoperability
Security is paramount in Spatial Data Infrastructures (and more generally in research
infrastructures) as broad engagement from resource/service providers and research
communities is dependent on securing access to online data resources and services
without disrupting end-users and applications developers accustoming (best
practices/way of working). A number of initiatives have investigated cross-
infrastructure federation and interoperability while addressing the need for user-
friendly features such as single-sign on (SSO). The main aspects that GENESI-DEC
will consider in this context are:
architectural design and implementation of a federated security
interoperability framework to meet GENESI-DEC stakeholders
requirements;
implementation of bridges to support the mapping of specific security
models and technologies used by GENESI-DEC stakeholders and services to
this framework;
development of user-friendly paradigms and interfaces for sign-on and
management of access rights.
The basic idea is to design and develop a brokering layer able, starting from the user
identity credential in the origin framework, to issue short-lived security tokens
suitable for the interaction with target resources/services and to support the delegation
of these tokens in order to allow further interactions on behalf of the user.
Research in this task will leverage related work carried out in on-going
initiatives/projects such as GENESI-DR, EGEE and GridShib. The
solutions/approaches to security that will be analysed and integrated from the
beginning of the project will be (a) Shibboleth with (b) X.509-based PKI and (c)
OpenId/OAuth with (b) X.509-based PKI. This also reflects the fact that leading
research and commercial infrastructures in Europe and world-wide providing access
to storage and computational resources (e.g. EGEE, Amazon EC2/S3 etc.) support (b)
for security whilst (a) and (c) are solutions well accepted and widely adopted by end-
users especially for browser-based interaction patterns.
The framework itself may exploit quite different technologies to provide the
mediation layer – among the options that will be considered are capability-oriented
computing to dynamically provision policy translation and enforcement for cross-
domain interactions.
5 Digital Earth Communities
GENESI-DEC aims to address Digital Earth Communities: a first set of these have
already been selected, while additional ones will be identified and addressed during
the project life.
While GENESI-DR was oriented towards the development and implementation of a
digital repositories distributed infrastructure, GENESI-DEC will focus on a number of
heterogeneous Digital Earth Communities, each with dedicated use cases:
The seafloor and ocean observation community;
The global atmosphere observation community using aircraft;
The global change Earth Observation community;
The territorial development and spatial planning community;
The Black Sea catchment observation community.
In order to establish a real and effective link with these communities (so to properly
gather and address their requirements) GENESI-DEC has already set up
collaborations with related and relevant projects and/or organizations. Some of these
projects have developed or are developing dedicated infrastructures (with data) to
serve some of the needs of their communities. GENESI-DEC will federate to or
interoperate with such dedicated DRs and infrastructures, bringing additional benefits
to the Digital Earth Community.
GENESI-DEC establishes key collaborations in the frame of Global Environmental
initiatives, such as the Global Earth Observation System of System (GEOSS), which
will provide decision-support tools to a wide variety of users, being a global and
flexible network of content providers allowing decision makers to access an
extraordinary range of information at their desk. This ‘system of systems’ will
proactively link together existing and planned observing systems around the world
and support the development of new systems where gaps currently exist. Within the
frame of a GEO-GEOSS work plan 2009-2011, the DA-09-02a GEO task for
effective management of large volumes and diverse types, an Alliance has been
proposed among selected data centres/projects (in particular DIAS, GIOVANNI and
GENESI-DR) to promote a common vision towards the GEOSS Common
Infrastructure.
6 Conclusions
By enlarging the GENESI-DR platform, GENESI-DEC addresses and embraces a
wide Digital Earth community. The project approach bridges the gaps among
different disciplines of Digital Earth Community, providing a common, standardised,
interoperable and multidisciplinary infrastructure, nonetheless able to address the
specific needs of the single disciplines. By providing single and simple service
interfaces to discovery, search, access and process on demand of many distributed
environmental data holdings, GENESI-DEC reduces the time-to-science to a
minimum and improves the effectiveness of many standard and complex operations
for the Digital Earth Community.
Acknowledgments. GENESI-DEC is co-funded by the European Commission, FP7,
grant agreement RI-261623.
References
1. GENESI-DEC, http://www.genesi-dec.eu
2. GENESI-DR, http://www.genesi-dr.eu