Greedy Heuristic Placement Algorithms in Distributed Cooperative Proxy System

摘要

In this paper, we investigate the object placement problem in distributed cooperative proxy systems and build a mathematics model. We prove that the problem is a NP-Hard problem and two novel greedy heuristic placement algorithms MWLC and MWGB are proposed to get the near-optimal answer in a polynomial complexity. We perform simulation and the results reported in this paper show that these two algorithms could achieve better performance than the traditional MFU algorithm (about 13.05% and 14.13% respectively). By the analysis of the experiment results, we find that the two algorithms can efficiently reduce the average request cost and balance the load of proxies. In general, the technologies proposed in this paper could be used to develop effective distributed cooperative proxy systems such as CDSP and digital library and so on.