A location model for web services intermediaries
Yi Sun, Gary J. Kœhler · 2003
In the recent past, Web services have entered the competition for distributed e-commerce platforms. By exploiting existing open standards such as XML and HTTP, Web services promise unprecedented levels of interoperation between programs on different frameworks. Questions remain on how to capitalize on this new technology. This dissertation attempts to answer the questions from a service location perspective. We focus on the behaviors of Web services intermediaries that serve as common interfaces to their clients and obtain Web services from independent Web services providers on behalf of their clients. The distributed nature of Web services and the ever-increasing prominence of network latency in determining server performance justify the study of locating servers of Web services intermediaries on the Internet to optimize their performance and/or financial goals. We propose a mathematical integer programming model to help these intermediaries decide on the locations and usage rates of their servers. As expected, the proposed model becomes computationally intractable as the number of participants increases. We therefore develop an efficient heuristic method named DAL to tackle the problem. For the problems tested, the DAL heuristics provide near optimal solutions in short computer times and with limited computer memory usage.