Comap: A Cooperative Overlay-Based Mashup Platform

Recently, mashups have emerged as an important class of Web 2.0 collaborative applications. Mashups can be conceived as personalized Web services which aggregate and manipulate data from multiple, geographically-distributed Web sources. Mashups, while enhancing personalization, bring up new scalability and performance challenges. The fact that most existing mashup platforms are centralized further exacerbates the scalability challenges. Towards addressing these challenges, in this paper, we present the design, implementation, and evaluation of CoMaP - a cooperative information system for mashup execution. The design of CoMaP is characterized by a scalable architecture with multiple cooperative nodes distributed across the Internet and possibly multiple controllers which plan and coordinate mashup execution. In our architecture, an individual mashup can be executed at several collaborative nodes with each node executing part of the mashup. CoMaP includes a unique mashup deployment scheme that decides which nodes would be involved in executing an individual mashup and what operators they would host. Also, CoMaP continuously adapts to overlay dynamics and to user actions such as creation of new mashups or deletion of existing ones. Furthermore, CoMaP possesses failure resiliency feature which is necessary for cooperative information systems. Our experimental study indicates that the proposed techniques yield improved system performance.