Occurrences

Paper

../papers/02-02-04/02-02-04.html

Date of Presentation

Tuesday, 21 May

Time of Presentation

14.45

Presentation Level

In-The-Middle

Abstract

Web Services have captured everyone’s attention in the computer industry during the past year. Not all of the Web Services is hype. Although everyone is trying to take simple usage scenarios (for which web services may not be appropriate or necessary) to explain the concepts, it is important to discuss the technical challenges that face a developer or consumer of web services while developing enterprise class applications. Some of these challenges deal with reliability, failure-management, recovery, administration, tracing and logging of activities, business intelligence information capture, distributed transactions, heterogeneous security, distributed error/exception handling and so on. Many enterprise applications require most of these capabilities for business reasons. Most of the web services implementations and standards do not directly address these requirements. However, there are many existing solutions and technologies that allow developers and consumers of web services to meet many of these needs without having to develop everything from scratch. The biggest challenge that the developers have to deal with comes from the fact that Web Services are distributed by nature, asynchronous and run on top of HTTP connection (which by itself is not very reliable and passes through many security and firewall servers). A critical business application may suffer severely, if the application is not equipped to handle random failures, loss of services, unpredictable round-trips and distributed dependencies. With careful planning and right technical approach, such situations can be managed, even though they cannot be avoided. If one can find a comprehensive model that the operating engines for web services can understand and act upon them, then they may be able to solve their problem. In this paper, we will first discuss a list of issues that are relevant to web services. Then we will focus on how XML based approaches and modeling techniques make it possible to address these issues both within web services environment as well as outside. We will also discuss how existing infrastructures and technologies can help in developing web services frameworks that can meet all the requirements of an enterprise class application. Some implementation details for application developers will also be discussed especially focusing on Java technology for achieving the desired goals. We will also take a closer look at web services as ad-hoc application integration technique that benefits from the solutions discussed earlier in the presentation.