Chapter 1: Distributed Information Systems Gustavo Alonso Computer Science Department Swiss Federal Institute of Technology (ETHZ) alonso@inf.ethz.ch http://www.iks.inf.ethz.ch/ Contents - Chapter 1 Design of an information system Layers and tiers Bottom up design Top down design Architecture of an information system One tier Two tier (client/server) Three tier (middleware) N-tier architectures Clusters and tier distribution Communication in an information system