4a.1 Grid Computing Standards ITCS 4010 Grid Computing, 2005, UNC-Charlotte, B. Wilkinson, slides 4a.

4a.2 Standards Bodies The primary standards-setting body is 1 : Global Grid Forum (GGF) –Started in 1998 –Meets three times a year, GGF1, GGF2, GGF3 … –More than 40 organizations involved and growing … Others: W3C consortium (Worlds Wide Web Consortium) –Working on standardization of web-related technologies such as XML –See OASIS (Organization for the Advancement of Structured Information Standards) IETF, DMTF 1 “The Grid Core Technologies” by M. Li and M. Baker, 2005, page 4.

4a.3 Standards in the Web Services World XML introduced (ratified) in 1998 SOAP ratified in 2000 Web services developed Subsequently, standards have been are continuing to be developed: –WSDL –WS-* where * refers to names of one of many standards

4a.4 Standards in the grid computing world Open Grid Services Architecture (OGSA) First announced at GGF4 in Feb 2002 OGSA does not give details of implementation.

4a.5 Grid computing software Started before standards became accepted. Gone through several development cycles:

4a.6 Originally own protocols were developed (e.g. GT2) Then OGSA (Open Grid Services architecture) standard and a specification called OGSI (Open Grid Service Infrastructure) was developed. Extended web service was invented called a grid service to embody state and transience. (GGF) Implemented in GT3. And Now relies more directly upon developing web service standards (GT 4)

4a.7 Grid computing standards Figure from “An ‘Ecosystem’ of Grid Components”, 2004, Grid Research Integration Deployment and Support Center, center.org/r6/ecosystem/ecology.php

4a.8 Open Grid Services Architecture (OGSA) Although OGSI vanished, OGSA continues …

4a.9 OGSA Defines standard mechanisms for creating, naming, and discovering service instances. Addresses architectural issues relating to interoperable services for grid computing. Originally described in “The Physiology of the Grid”

4a.10 WS-Resource Framework A specification developed by OASIS, essentially to replace OGSI and make the implementation of a stateful web service acceptable. Specifies how to make web services stateful and other feature, without drifting from the original web services concept.

4a.11

4a.12 From “The Globus Toolkit 4 Programmer’s Tutorial” by Borja Sotomayor.

4a.13From “The Globus Toolkit 4 Programmer’s Tutorial” by Borja Sotomayor.

4a.14 WS-* Standards Principal web service standards adopted for grid computing: WSRF Framework collection of 5 specifications: –WS-ResourceProperties Specifies how resource properties are defined and accessed –WS-ResourceLifetime Specifies mechanisms to manage resource lifetimes –WS-ServiceGroup Specifies how to group services or WS-Resources together –WS-BaseFaults Specifies how to report faults

4a.15 WS-* Standards continued WS-Notification –Collection of specifications that specifies how configure services as notification producers or consumers WS-Addressing –Specifies how to address web services. –Provides a way to address a web service/resource pair

4a.16 GT 4 Stateful Web Services Web services as created in assignment 1 are stateless. Stateful web services required for grid computing. Obtained in WS-RF by having a web service front- end to a stateful “resource.”

4a.17 Web Service Resource Resource properties Client Web Service Resource Framework (WS-RF) Holds information retained between accesses.

4a.18 Example with a “database” resource The Grid 2: Blueprint for a new Computing Infrastructure, Ian Foster, Carl Kesselman and Steve Tuecker Editors, Morgan Kaufmann Chapter 17: “The Open Grid Service Architecture,” by Ian Foster, Carl Kesselman and Steve Tuecker.

4a.19 In this example, the client accesses a file transfer service to perform actions such as transfer a file from one storage service to another. Because based upon web services, uses web services technology, XML, WSDL, etc.

4a.20 WSDL file with WS-RF Serves the same purpose as the WSDL file in web services – to define the service interface. A significant addition in the WSDL file is to specify the resource.

4a.21 Service Interface If service implements operations on WSRF resource properties, WSDL will include definitions relating to resource property.

4a.22 Service Implementation If service uses WS-RF mechanisms, implementation must include code for resource implementation and resource home.

4a.23 More detail on WS-RF when we do assignment 2, which asks us to create a Globus 4 service. GT 4 uses WS-RF. First though, let us look at GT4.