Denis Caromel1 OASIS, Univ. of Nice Sophia-Antipolis, INRIA -- CNRS - I3S -- IUF October Web Services Resource Framework 2. Grid scalability 3. Questions Stateful vs. Stateless Web Services for the Grid: how to get both Scalability and Interoperability ?

Denis Caromel2 Why is WSRF Web Services Resource Framework the silver bullet for the GRID ?

Denis Caromel3 WSRF in (very) short Web Service: A service with an interface defined in a machine-processable format: WSDL Usually Stateless (Reliability + Scalability: restart, duplicate, relocate …) WSRF: Standard representation of :State, and relation WS State Stateful Resource (SR): type of SR = XML definition (XML schema) Implied Resource Pattern: An Endpoint reference to a WS (WS-Addressing) includes an implicit SR id Stateful Resource in WSRF = Resource Id referenced in a WS endpoint, State managed by Web Services messages

Denis Caromel4 WSRF in a picture Intel Xeon 3.20Ghz 2500 Collaborative White Board, Wiki Phil...

Denis Caromel5 WSRF in a picture Collaborative White Board, Wiki Web Server Web Service http address clusterX Implied Resource Pattern

Denis Caromel6 Enterprise Grids Internet EJBServlets Apache Databases

Denis Caromel7 Scientific Grids Internet Clusters Parallel Machine Large Equipment

Denis Caromel8 GRIDs: Server to Peer-To-Peer (P2P) Internet EJBServlets Apache Databases Does WSRF scale ?

Denis Caromel9 A few Questions: Why is it so important to have: stateless WS + set apart stateful Resources ? Why not have a lot of stateful WS closer to the resources ? … P2P Grid Is the one-to-one mapping from WS endpoint to SR type a limitation ? Locality, duplication/cache, coherency protocols: what is the WSRF answer ? Stateful vs Stateless: any lesson learned from passed Dist. // Functional systems ? Besides infrastructure, what role for WSRF in Program. Environment, PSE,... ? Why is WSRF a silver bullet for the Grid ?