A simulation study of the effects of multi-path approaches in e-commerce applications

Response time is a key factor of any e-commerce application, and a set of solutions have been proposed to provide low response time despite network congestions or failures. Being them mostly based on caching of Web objects and replication of DBMS managed data at the edges, or at intermediate points, of the Web infrastructure, they reveal effective when handling client requests only performing read access to application data. However, any update request typically needs to be redirected to the origin DBMSs, hence not taking advantage from data replication and related client proximity. In order to alleviate the effects of network congestions or failures, we have proposed a multi-path protocol that increases the likelihood for the update request to be processed along a responsive (e.g. failure free) network path in between the client location and the origin DBMS sites. In this paper we present an extensive simulation study of the effects of such a multi-path approach on the client perceived response time. The study relies on both Brite generated network topologies and the NLANR graph. Also, well known realistic TCP models are used to capture the effects of network delays during both normal and anomalous (i.e. packet loss affected) operation mode