Semantic Grid

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David De Roure Carole Goble www.semanticgrid.org
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So what is the Semantic Grid?

• The Semantic Grid is an extension of the current
  Grid in which information and services are given
  well-defined meaning, better enabling computers
  and people to work in cooperation
• The full richness of the Grid ambition depends
  upon realising the Semantic Grid
• Semantics are key to virtualisation and
  abstraction in the Grid
• This talk explains the motivation and state of
  the art in the Semantic Grid, and identifies
  future collaborations

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Vision The Grid

• Grid computing has emerged as an important new
  field, distinguished from conventional
  distributed computing by its focus on large-scale
  resource sharing, innovative applications, and,
  in some cases, high-performance orientation...we
  define the "Grid problemas flexible, secure,
  coordinated resource sharing among dynamic
  collections of individuals, institutions, and
  resources - what we refer to as virtual
  organizations
• From "The Anatomy of the Grid Enabling Scalable
  Virtual Organizations" by Foster, Kesselman and
  Tuecke

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Grid Services

• Building systems by composition of heterogeneous
  components demands that we standardise common
  patterns
• Approach to resource identification
• Lifetime management interfaces
• Inspection monitoring interfaces
• Base fault representation
• Service and resource groups
• Notification
• More than basic Web Services!

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The Semantic Grid Problem

• Wish to reuse
• Data
• Services
• Knowledge
• Software
• Anticipated use
• Unanticipated use

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Two infrastructure enablers
Grid Computing
Semantic Web

• On demand transparently constructed
  multi-organisational federations of distributed
  services
• Distributed computing middleware
• Computational Integration

• An automatically processable, machine
  understandable web
• Distributed knowledge and information management
• Information integration

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Origins of the Semantic Web

• The Semantic Web is an extension of the current
  Web in which information is given a well-defined
  meaning, better enabling computers and people to
  work in cooperation.
• It is the idea of having data on the Web defined
  and linked in a way that it can be used for more
  effective discovery, automation, integration and
  reuse across various applications.
• The Web can reach its full potential if it
  becomes a place where data can be processed by
  automated tools as well as people.
• W3C Activity Statement

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Making Knowledge Explicit
Ontology Inference Layer
DAML
OIL
RDF
DAMLOIL
All influenced by RDF
OWL Lite (thesaurus) OWL DL (reason-able) OWL
Full (anything goes)
OWL
OWL Web Ontology Language
RDF Resource Description Framework
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Compare and Contrast
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Semantics in and on the Grid
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Building bridges
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Semantic Grid
SemanticWeb
SemanticGrid
Scale of Interoperability
ClassicalWeb
ClassicalGrid
Scale of data and computation
Based on an idea by Norman Paton
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OntoGrid Objectives

• Strategic
• Pioneer the use of Knowledge Technologies (KT) to
  enhance and extend architecture and design of
  Grid computing systems
• Enable Deployment of Knowledge Technologies in
  Grid Architectures
• Deploy prototypes in the context of real world
  Business Applications

• Technical
• Knowledge Services that are Grid Aware and Grid
  Compliant
• Grid Services that are Knowledge Aware

Knowledge Aware
Grid Aware
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State of Art Innovation

• Knowledge and semantic metadata typically
  distributed, heterogeneous, often implicit or
  embedded in Grid apps

• Explicit metadata representations using shared
  Ontology Services

• Ad-Hoc adoption of ontologies

• Use of standardised languages

• Centralised Ontology Services

• Grid Aware Ontology Services

• Hardwired coordination, and task/resource
  allocation

• Agent-based techniques for coordination and
  cooperation

• Lack of appropriate models/methodologies

• Combinations of ontology engineering and agent
  systems development methodologies

• Assumes small/medium scale, stability and
  homogeneity of resources and user access patterns

• P2P Techniques to support large scale, dynamic,
  heterogeneous resources and access

• Debugging at the symbol level

• Intelligent debugging tools utilising knowledge

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Semantic Grid security and trust policies,
management and frameworks
Resource selection scheduling
Ontologies for service classification
Knowledge Representation for Semantic Grid
Services
Semantic interoperability and integration
Semantics in Agent Communication Languages
Workflow and schedule repair
Knowledge-based provenance and audit trails
Semantics for service delegation and knowledge
aggregation
Service Negotiation
Quality of service and service level agreement
management
(Semantic) event notification
Models for quality and accessibility of data
sources, incl. versioning, recoverability, etc.
Lifetime management
Architectures for supporting Semantic Grid
Services
New models for fault tolerance and dependability
(Semantic) Service state
Virtualisation and provisioning of knowledge
service
Audit trails over transient state
Naming
Scaleable service composition for heterogeneous
environments
Service enactment/invocation frameworks
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Building Bridges
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Concertation

• Issues arising in SG session
• What you can and cannot do with OWL
• Pushing semantics into the grid structure
• Database interoperability
• Explicit representation of knowledge about how
  things are working
• Privacy and Security
• Processes Workflow at the business/technical
  Level
• Standard vocabularies for use in SLAs
• Actions
• Grid resource description
• Semantic Grid topic map

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Community collaboration

• Short term
• Grid resource and job description
• Semantic Web Services (OWL-S, WSMO)
• Standards, use cases
• Demos across heterogeneous services/stores/grids
• Software reuse
• Medium term
• Agent-based negotiation of SLAs
• Semantic annotation for Grid services and content
• P2P, Deployment and (self-)management
• Grid and ambient intelligence

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Community Events

• GGF13 Agents and Semantic Grid meeting
• Spring concertation meeting
• CCGrid 2005 Semantic infrastructure for Grid
  Applications workshop
• Semantic Grid The Convergence of Technologies-
  Schloss Dagstuhl Seminar, July 2005
• Concertation arising from September meeting
• Training (De Roure)
• Resource Description ontology (Brooke)
• Semantic Grid topic map (Goble)

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Closing Remarks

• Both Grid and Semantic Web are about joining
  things up
• We need to bridge communities to achieve the
  vision
• See www.semanticgrid.org
• Contact

Carole Goble University of Manchester carole_at_cs
.man.ac.uk
David De Roure University of Southampton dder_at_e
cs.soton.ac.uk