With the explosion in Global Networks such as the Web, communities take advantage sharing and working with the big amount of information and services available. Within this context a promising area for the communities when dealing with the information on the man-machine interface is Distributed Virtual Reality. However, distributed applications must deal with issues such as robustness, scalability, heterogeneity, uncertain online inputs and good Quality of Service (QoS). The work presented in this paper describes our enterprise improving the QoS of DVRMedia, a Multi-User Virtual Reality system for the Web. This tentative brings us to deal with an abstract model so called the k-server problem. We propose a solution with the integration of two paradigms: online algorithms and mobile agents. Both paradigms allow us to design a scheme for improving the QoS and to drive an implementation in Java. The solution is validated with experiments and its implementation on DVRMedia.