This article addresses the problem of programming by combining already existing programs on the INTERNET. For this, an interpreter based language called Progress is presented. Progress makes it possible to use and combine programs and functionalities provided by various servers in a simple and elegant way, similar to what a UNIX shell does for locally available programs. Moreover, the inherent parallelism, which is given due to the fact that programs may reside on different hosts, can be fully exploited in Progress. Other important features of Progress are that the language can be extended by new data types and that it is embeddable in other software systems. This article presents the main concepts and ideas of Progress and gives an overview of the language. 1. Introduction This article addresses the problem of "large-scale programming ", which means programming by combining already existing programs and services, which may reside on one or more computer systems. For instance, typic...

DecisionNet is a distributed, Web-based electronic market for decision technologies such as data, models, solution algorithms, and modeling environments. Consumer-provider interactions are facilitated by model management software agents provided by DecisionNet. To illustrate different approaches for designing this agent functionality, we present two agents that embody different designs for mediating consumer and provider interaction with the AMPL and GAMS modeling environments. The AMPL agent is lean, and places significant knowledge and reasoning requirements on both providers (when registering a technology) and consumers (when using technologies). In contrast,the GAMS agent encapsulates knowledge of the GAMS language and modeling environment to facilitate registration of models by providers and to create a run time interface to models for consumers. We discuss the relative advantages of both approaches and argue for the need incorporate them into environments such as DecisionNet. 1 ...

The system Progress facilitates the easy provision and usage of computational services via the INTERNET. Moreover, it offers powerful value added services in this area. The concept of plans can be used to combine computational services located at different hosts to more powerful services. In this article, we demonstrate how this concept can be coupled with other INTERNET technologies like Java to achieve a visual programming environment for large-scale INTERNET programming. 1. Introduction Over the last years, a lot of new technologies have been developed to use computational services (programs or algorithms) via networks and in particular via the INTERNET. While Java, ActiveX, and Javascript may be the most important technologies for client-side computing, server-side computing can be handled with CGI, Java RMI, CORBA [11, 9], and RPC [6]. With the system Progress [1, 3, 2], which we have developed, we follow similar aims like the above mentioned technologies for server-side computi...