A Collaborative Approach for Caching Dynamic Data in Portal Applications

Portals are one of the rapidly growing applications on the Web, providing a single interface to access different sources (providers). Providing fast response time is one of the critical issues in such applications. Dissatisfaction of users dramatically increases with increasing response time, resulting in abandonment of Web sites, which in turn could result in loss of revenue by businesses. In this paper we address the performance of such applications through caching techniques. We discuss the limitations of existing solutions and introduce a caching strategy based on collaboration between the portal and its providers. Providers trace their logs, extract information to identify good candidates for caching and notify the portal. Caching at the portal is mainly decided based on scores calculated by providers and associated with objects. We evaluate the performance of the collaborative caching strategy using simulation data. We also address the issue of heterogeneous scoring policies by different providers and introduce mechanisms to regulate caching scores.