ACADEMIA

By Steve Fisher, Editor -- As we’re all aware, there has been a great deal of attention and publicity about grid computing recently. Frankly, it's warranted. One important component of grid computing however has not received quite as much attention, Web services. So to learn more, and throw a little light on the subject Supercomputing Online turned to Sri Mandyam, Director of Product Architecture at United Devices. SCO: How do you define the term “Web services?” MANDYAM: The term Web services describes a standardized way of integrating applications using the XML, SOAP, WSDL and UDDI open standards over an Internet protocol backbone such as HTTP. •XML is used to describe the data •SOAP is used to transmit the data •WSDL is used for describing the application interface as a services •UDDI is used for listing what services are available and where they are located Unlike traditional client/server models, such as a Web server/Web page system, Web services do not provide the user with a GUI. Web services instead share business logic, data and processes through a programmatic interface across a network. Developers can then add the Web service to a GUI (such as a Web page or an executable program) to offer specific functionality to users. Web services allow different applications from different sources to communicate with each other without time-consuming, custom coding. Because all communication is in XML, Web services are not tied to any one operating system or programming language. For example, Java can talk with Perl and Windows applications can talk with UNIX applications. SCO: How do Web services benefit customers? MANDYAM: The Web services standard was primarily intended for business applications to interoperate with each other without knowledge of their respective internal implementations. Since the cost of developing interoperability among proprietary applications can be very high, customers benefit from purchasing Web services-enabled applications that are pre-designed for interoperability. From another viewpoint, Customers can advertise their Web services-enabled applications as services. These advertised services may then be dynamically discovered by applications and software developers using standards such as, UDDI. SCO: How do Web services play a role in the future of the Grid? MANDYAM: The promise of grid computing is to integrate a variety of systems into a virtual supercomputer capable of aggregating resources such as, processor cycles and storage within a large network consisting of one or more organizations. This far-reaching vision experienced a setback, however, by a lack of interoperability standards among grid computing technologies that were being used in the individual organizations. The advent of Web services has revived the vision by allowing grids to be specified as services that can interoperate with each other. The interoperability benefits in grid computing come in two areas: one is in the area of tying together heterogeneous resources managed by different grid technologies. The development of Web services-based standards will specify XML-based languages for these technologies to talk to each other. Secondly, the interoperability will extend to existing infrastructures enterprises have in place today. Web services-based interfaces will permit companies to integrate grid computing frameworks more easily into their environments because Web services-based development is designed to be easier and faster than traditional methods. Interfaces described in WSDL will provide the flexibility for companies to build higher-level, Web services-based applications that can also be discovered and shared. A grid service is built on concepts and technologies from the Grid and Web services communities, such as the W3C and GGF/OGSA, and will be the basis of Web services influence on grid computing. Its architecture defines standard mechanisms for creating, naming, and discovering grid service instances: providing location transparency, network and platform heterogeneity. The Open Grid Services Architecture (OGSA) is in the process of defining a set of Web Services Description Language (WSDL) interfaces and for creating, managing and securely accessing large computational grids. SCO: So would you say that it’s critical for companies with Grid solutions to plan for Web services in their architecture? MANDYAM: Yes, there is unanimous support for a fusion of Web services with Grid services in the grid computing space, and both major and small vendors are embracing the OGSA standards. Fortunately for companies, Web services will make grid solutions easier to implement and more powerful. Vendors will be to make their product architectures compliant. Large and progressive enterprises that are planning to deploy enterprise-wide grid solutions should definitely review and follow the standards being specified by the OGSA. In some cases, it may be necessary for enterprises to actively participate in GGF/OGSA to incorporate business critical features into OGSA standards. SCO: Does the advent of Web services lead to the potential for a worldwide, Internet grid? MANDYAM: As enterprises begin advertising their grid service capabilities using OGSA-based WSDL interfaces, there will be a strong desire among government organizations and private enterprises to build a worldwide Internet grid. However, such a grid would require a lot of cooperation among the various IT departments to develop and implement usage and access control policies. Web services will be secondary to enhancing this potential, as the important milestone will be a general agreement on standards for interoperability. Web services seem to be fueling that through support for the OGSA. SCO: On Monday UD announced the availability of the MetaProcessor platform 3.0. Please tell the readers about it. MANDYAM: The MetaProcessor platform v3.0 is United Devices' latest version of its computing platform for building grids that harness underutilized compute resources on Windows and Linux. The platform allows companies to effectively incorporate their desktops into enterprise grids capable of delivering a high performance computing engine. The platform builds on its recognized ease of manageability and scalability to add important features that make the product easier to integrate and use. It offers a SOAP-based interface and WSDL specification which companies can use to more easily integrate the grid into their infrastructure and to package research applications with Web services. The platform adds the ability to submit and run simple batch jobs that are not as computationally demanding via command line, as opposed to data-intensive high throughput jobs that the platform was originally designed for. Lastly, getting applications onto the platform has also become easier with a simplification of the migration process for application developers. No API's are necessary to access the platform's robust security and network optimization features such as data encryption and compression, and applications can be run without source code modification whatsoever.