Grid Services currently deal with this semantic infrastructure in ad-hoc and hidden ways, providing poor mechanisms for sharing and openly processing knowledge. This makes the knowledge hard to share, and hard to interpret by services other than the originators. Often these schemas are fixed, which makes them rather inflexible. Much of the metadata is hard-coded and buried in code libraries, type systems, or grid applications. This makes it hard to adapt and configure. Finally, understanding and know-how is frequently tacit, embedded in best practice and experience rather than explicitly recorded. This makes sharing, customisation and adaptation difficult, and dependent on scarce human effort. The Semantic Grid aims to provision a semantic infrastructure for Grid infrastructure to improve sharing, enable unanticipated reuse of resources, support interoperability and enable more flexible and configurable middleware.
OntoGrid is a step towards the Semantic Grid. There are many challenges to explore. Many are technical—architectural or theoretical foundations, the maturity of semantic and grid technologies, their appropriateness for the required tasks, their scalability, the separation of grid level and application specific semantics, and making it easier not harder by combining semantic infrastructure with Grid computing infrastructure. Others are operational—gathering and maintaining the semantic content, reliance on unavailable tooling, and convincingly showing the added value of semantics when the return on investment may come downstream, be long term and benefit developers other than the originators. Some are sociological and political—the interplay between the Semantic and the Grid communities, the inter-factional battles within those communities and the legal, security and privacy implications of clearly exposed metadata and automated reasoning.
| Glossary | |
| BIRN | Biomedical Informatics Research Network. An NIH initiative supporting distributed collaborations in biomedical science. http://www.nbirn.net/ |
| CIM | Common Information Model. A common definition of management information for systems, networks, applications and services. http://www.dmtf.org/standards/cim/ |
| CMCS | Collaboratory for Multi-scale Chemical Science. Project supporting collaboration through the use of adaptive infrastructure. http://cmcs.ca.sandia.gov/ |
| DFDL | Data Format Description Language. A language for describing the structure of binary and character encoded (ASCII/Unicode) files and data streams. http://forge.gridforum.org/projects/dfdl-wg/ |
| EGEE | Enabling Grids for E-SciencE. EU funded project building grid infrastructure for scientists. http://public.eu-egee.org/ |
| GGF | Global Grid Forum. The community of users, developers, and vendors leading the global standardization effort for grid computing. http://www.ggf.org/ |
| gLite | A lightweight middleware framework from the EGEE project. http://glite.web.cern.ch/glite/ |
| GT(4) | Globus Toolkit (4). An open source software toolkit used for building Grid systems and applications. Developed by the Globus Alliance. http://www.globus.org/toolkit/ |
| JSDL | Job Submission Description Language. https://forge.gridforum.org/projects/jsdl-wg/ |
| Matlab | A language and environment supporting computationally intensive tasks. http://www.mathworks.com/ |
| OGSA | Open Grid Services Architecture. A set of core capabilities and behaviours that address key concerns in Grid systems. http://www.globus.org/ogsa/ |
| OGSA-DAI | OGSA Data Access and Integration. Middleware to assist with access and integration of data from separate data sources via the grid. http://www.ogsadai.org/ |
| OMII | Open Middleware Infrastructure Institute. An EPSRC funded initiative providing reliable, interoperable and open-source Grid middleware. http://www.omii.ac.uk/ |
| P2P | Peer to Peer. Architectures which allow autonomous peers to interoperate in a decentralized, distributed manner for fulfilling individual and/or common goals |
| SAML | Security Assertion Markup Language. A language for exchanging authentication and authorization data between security domains. http://www.oasis-open.org/committees/tc_home.php?wg_abbrev=security |
| S-OGSA | Semantic OGSA. |
| VO | Virtual Organisation. Flexible, secure, coordinated resource sharing among dynamic collections of individuals, institutions, and resources. |
| VOMS | Virtual Organisation Management Service. A service managing a VO. |
| WSRF | Web Services Resource Framework. A framework defining conventions for modelling and accessing stateful resources using Web services http://www.globus.org/wsrf/ |
2 J. Hendler "Science and the Semantic Web," Science 299: 520-521, 2003.
3 L. Pouchard, L. Cinquini, B. Drach, et al., "An Ontology for Scientific Information in a Grid Environment: the Earth System Grid," CCGrid 2003 (Symposium on Cluster Computing and the Grid), Tokyo, Japan, May 12-15, 2003.
4 www.semanticgrid.org/
5 www.dagstuhl.de/05271/
6 D. De Roure, Y. Gil, J. Hendler "Guest Editors' Introduction: E-Science," IEEE Intelligent Systems 19(1), Jan/Feb 2004: 24-25.
7 C. Wroe, C. Goble, M. Greenwood, P. Lord, S. Miles, J. Papay, T. Payne, L. Moreau. "Automating Experiments Using Semantic Data on a Bioinformatics Grid," IEEE Intelligent Systems special issue on e-Science Jan/Feb 2004.
8 L. Chen, N.R. Shadbolt, C.A. Goble, F. Tao, S.J. Cox, C. Puleston, P.R. "Towards a Knowledge-based Approach to Semantic Service Composition" 2nd International Semantic Web Conference, 20-24 October, 2003, Sanibel Island, Florida, USA.
9 J. D. Myers, C. Pancerella, C. Lansing, K. L. Schuchardt, B. D. "Multi-Scale Science: Supporting Emerging Practice with Semantically Derived Provenance," Proceedings of the Workshop on Semantic Web Technologies for Searching and Retrieving Scientific Data at Sanibel Island, Florida on October 20, 2003.
10 H. Fu. J. G. Frey. "Semantic description and tracking of analysis of chemical data," Second International Workshop on the Knowledge Grid and Grid Intelligence, Beijing, China, 2004, 140-149.
11 S. Bowers and B. Ludäscher "An Ontology-Driven Framework for Data Transformation in Scientific Workflows," Internaltional Workshop on Data Integration in the Life Sciences (DILS' 04), March 25-26, 2004 Leipzig, Germany, LNCS 2994.
12 M. Bachler, S. Shum, Y. Chen-Burger, J. Dalton, D. De Roure, M. Eisenstadt, J. Frey, J. Komzak, D. Michaelides, K. Page, S. Potter, N. Shadbolt, A. Tate, "Collaboration in the Semantic Grid: a Basis for e-Learning," Grid Learning Services (GLS 2004) at the 7th International Conference on Intelligent Tutoring Systems Workshop (ITS 2004), (Maceio, Brazil, 2004), 1-12.
13 www.ontogrid.net/
14 Foster, H. Kishimoto, A. Savva, D. Berry, A. Djaoui, A. Grimshaw, B. Horn, F. Maciel, F. Siebenlist, R. Subramaniam, J. Treadwell, J. Von Reich, "The Open Grid Services Architecture," www.ggf.org/documents/GFD.30, 2005.
15 OGSA Data Access and Integration. Middleware to assist with access and integration of data from separate data sources via the grid.
16 www.globus.org/
17 public.eu-egee.org/
18 www.omii.ac.uk/
19 N. Sharman, N. Alpdemir, J. Ferris, M. Greenwood, P. Li and C. Wroe, "The myGrid Information Model," Proceedings of UK e-science All Hands Meeting, 2004, available from www.mygrid.org.uk/
20 Common Information Model (CIM) A common definition of management information for systems, networks, applications and services. www.dmtf.org/standards/cim/
21 Job Submission Description Language forge.gridforum.org/projects/jsdl-wg/
22 Knowledge Parser www.isoco.com/en/innovation/applications/kp.html
23 Z. Kaoudi, I. Miliaraki, S. Skiadopoulos, M. Magiridou, E. Liarou, S. Idreos, and M. Koubarakis, "Specification and Design of Ontology Services and Semantic Grid Services on top of Self-organized P2P Networks." OntoGrid Deliverable D4.1, 2005.
24 C. Goble, A. Gómez-Pérez, R. González-Cabero, M. S. Pérez. "ODESGS Framework, Knowledge-based markup for Semantic Grid Services," Proceedings of the Third International Conference on Knowledge Capture (K-CAP 2005), Banff, Canada, 2005, 199:200.
