Web services, with an emphasis on open standards and flexibility, may provide benefits over existing capital markets integration practices. However, web services must first meet certain technical requirements including performance, security and fault--tolerance. This paper presents an experimental evaluation of SOAP performance using realistic business application message content. To get some indication of whether SOAP is appropriate for high performance capital markets systems, the results are compared with a widely used existing protocol. The study finds that, although SOAP performs relatively poorly, the difference is less than in scientific computing environments. Furthermore, we find that in realistic business applications it is possible for text--based wire formats to have comparable performance to binary, and that the text--based nature of XML is not sufficient to explain SOAP's inefficiency. This suggests that further work may enable SOAP to become a viable wire format for high performance business applications.

Flexible and high-performance data exchange is becoming increasingly important. This trend is due in part to the growing interest among highperformance researchers in tool- and component-based approaches to software development. In trying to reap the well-known benefits of these approaches, the question of what communications infrastructure should be used to link the various application components arises. Traditional HPC-style communication libraries such as MPI offer good performance, but are not intended for loosely-coupled systems. Object- and metadatabased approaches like XML offer the needed plug-and-play flexibility, but with significantly lower performance.

GridRPC is a class of Grid middleware for scientific computing. Interoperability has been an important issue, because current GridRPC systems each employ its own protocol. Web services, where XML-based standards such as SOAP and WSDL are expected to see widespread use, could be the medium of interoperability; however, it is not clear if 1) XML-based schemas have sufficient expressive power for GridRPC, and 2) whether performance could be made sufficient. Our experiments indicate that the use of such technologies are more promising. than previously reported. Although a naive implementation of SOAP-based GridRPC has severe performance overhead, application of a series of optimizations improves performance. However, encoding of various features of GridRPC proved to be somewhat difficult due to WSDL limitations. The results show that GridRPC systems can be based on Web technologies, but there needs to be work to extend WSDL specifications, possibly impacting OGSA-based Grid services directions. 1.

There is substantial interest in using SOAP (Simple Object Access Protocol) in distributed applications' inter-process communications due to its promise of universal interoperability. The utility of SOAP is limited, however, by its inefficient implementation, which represents all invocation parameters in XML, for instance. This paper aims to make SOAP useful for high end or resource-constrained applications. The basic idea is to replace SOAP's XML/Ascii-based parameter representations with binary ones. Using SOAP's WSDL parameter descriptions, XML-based parameters are automatically represented as corresponding structured binary data, which are then used in all clientserver communications. Data is up- or down-translated to/from XML form only if and when needed by end points. The resulting SOAP-bin communication protocol exhibits substantially improved performance compared to regular SOAP communications, particularly when used in the internal communications occurring across cooperating client/servers or servers. Gains are particularly evident when the same types of parameters are exchanged repeatedly, examples including transactional applications, remote graphics and visualization, distributed scientific codes. A further improvement to SOAP-bin, termed SOAP-binQ, addresses highly resource-constrained, time-dependent applications like distributed media codes, where scarce communication bandwidth, for example, may prevent end users from interacting in real-time. SOAP-binQ offers additional quality management functions that permit SOAP to reduce parameter sizes dynamically, as and when needed. The methods used in size reduction are provided by end users and/or by applications, thereby enabling domain-specific tradeoffs in quality vs. performance, for example. An adaptive use...

XML provides flexible, extensible data models and type systems for structured data, and has found wide-acceptance in many domains. XML processing can be slow, however, especially for scientific data, thus leading to the conventional wisdom that XML is not appropriate for such data. Instead, data is stored in specialized binary formats, and is transmitted via work-arounds such as attachments and base64 encoding. Though these work-arounds can be useful, they nonetheless relegate scientific data to second-class status within the web services framework; and they generally require yet another API, data model, and type system. An alternative solution is to use more efficient encodings of XML, often known as “binary XML”. Using XML uniformly throughout an application simplifies and unifies design and development. In this paper we present a binary XML format and implementation for scientific data called Binary XML for Scientific Applications (BXSA). We show that performance is comparable to that of commonly used scientific data formats such as netCDF. These results challenge the prevailing practice of handling control and data separately in scientific applications, with web services for control and specialized binary formats for data. 1.

Web services, with an emphasis on open standards and flexibility, may provide benefits over existing capital markets integration practices. However, web services must first meet certain technical requirements including performance, security and fault–tolerance. This paper presents an experimental evaluation of SOAP performance using realistic business application message content. To get some indication of whether SOAP is appropriate for high performance capital markets systems, the results are compared with a widely used existing protocol. The study finds that, although SOAP performs relatively poorly, the difference is less than in scientific computing environments. Furthermore, we find that in realistic business applications it is possible for text–based wire formats to have comparable performance to binary, and that the text–based nature of XML is not sufficient to explain SOAP’s inefficiency. This suggests that further work may enable SOAP to become a viable wire format for high performance business applications.

Abstract. Aside from business processes, the service-oriented approach— currently realized with Web services and BPEL—should be utilizable for data-intensive applications as well. Fundamentally, data-intensive applications are characterized by (i) a sequence of functional operations processing large amounts of data and (ii) the delivery and transformation of huge data sets between those functional activities. However, for the efficient handling of massive data sets, a significant amount of data infrastructure is required and the predefined ’by value ’ data semantic within the invocation of Web services and BPEL is not well suited for this context. To tackle this problem on the BPEL level, we developed a seamless extension to BPEL—the ’BPEL data transitions.’ 1

Abstract — Admitting that the quality of a decision depends on the quality of the knowledge used to make it, it is argued that the enhancement of the decision making efficiency and effectiveness is strongly related to the appropriate exploitation of all possible organizational knowledge resources. On the other hand, software is perceived as an encapsulation of knowledge. Especially software tools offering Knowledge Management can become substantial organizational artifacts. Developing such tools should be in absolute compliance with the organizational practices so as to be easily integrated with and augment every day activities. Towards this end, this paper presents a multidisciplinary approach for developing knowledge management services for the capturing the organizational knowledge in order to augment teamwork in terms of knowledge elicitation, sharing and construction, thus enhancing decision making quality. Based on a properly defined ontology model, our approach is supported by a web-based tool that serves as a forum of reciprocal knowledge exchange, conveyed through structured argumentative discourses, the ultimate aim being to support the related decision making process.

A basic requirement in any successful application of a web-based system, such as Internet-based control systems, is the provision of efficient real-time processing and data transfer over the Internet. In a significant number of real-world environments, real-time web-based systems involve the transfer and exchange of large amounts of numerical data over the Internet. The heterogeneity and limited traffic resources of the Internet considerably complicate the transfer of such bulky data; for example, if a number of clients simultaneously try to connect with the same server or multiple data sources are accessed over the Internet via different platforms. Such situations require that a data transfer format has to be acceptable to heterogeneous platforms. Additionally, large amounts of data, such as graphics, desktop videos, and images uploaded to the Internet (which may sometimes consist of gigabytes of data), are increasingly being accessed, while, at the same time, the bandwidth available for communication is limited because of the increasing popularity of the Internet. Most relevant research on real-time data transfer has focused on the data