Designing a distributed cache infrastructure to improve the Web performance for the users of a large-scale organization is a difficult task. It is hard to determine how many caches are required, how to size each one, where to place them and how they should cooperate. To guide the decisions of system administrators, we propose Saperlipopette!, a tool that can be used to evaluate, \emph{a-priori}, the quality of the service offered by each potential configuration of the distributed cache infrastructure. Saperlipopette is based on trace-driven simulations. Our methodology is two-fold. First, we monitor the targeted organizations' Web related activity. This audit phase may last a couple of months; it captures the Web access pattern, the accessed documents history and the network characteristics. Second, we replay the organization's access pattern while simulating the distributed Web support infrastructure. To decide which configuration to use, a system administrator needs only run Saperlipopette! for each candidate configuration and then to compare the quality of service offered by each. This report presents the information gathering as well as the design of the tool. Saperlipopette! has been prototyped and is being used to evaluate the optimal distributed cache for INRIA. We show that beyond a certain cache's size, the performance stays constant whereas the consistency continues to decrease. We also evaluated a number of distributed configurations, among which peer-to-peer Relais cooperation proved to be the best one.