In this thesis, we study information service systems from two perspectives: one is about system and technical problems in Web cache management; another one focuses on business and operation management problems in information system services (ISS)....[ Read more ]

In this thesis, we study information service systems from two perspectives: one is about system and technical problems in Web cache management; another one focuses on business and operation management problems in information system services (ISS).

We first discuss efficient placement/replacement schemes for Web content caching based on the Knapsack model. To achieve the overall cluster efficiency, we develop a weighted load balancing (WLB) routing algorithm based on a dynamic programming routing model. The WLB algorithm considers both the cache ca-pability and content property to determine how to direct an arrival request to the right node. Extensive simulation results show that the WLB algorithm works well with the cluster content replacement schemes and together, they lead to shorter response time and higher cache hit ratio.

On the other hand, motivated by the new business models operated by many information service companies, we aim at developing insights into the determi-nants of the appropriate supply chain structure of ISS. We integrate the strategy issue and operation issue into the decision making process, to better understand how the service supply chain structure and pricing scheme affect the system per-formance and profit, so that firms may operate with the best design for key service dimensions. We consider the utility-maximization demand model, identify and evaluate methods of coordinating ISS supply chains in which multiple decision makers pursue individual benefits. We formulate the decision problem for each player based on Game Theory, derive the rational behaviors, and characterize the equilibrium results.