7. CONCLUSIONS
In this work we introduce a novel non-cooperative game model to characterize the caching problem among selfish servers without
any central coordination. We show that pure strategy Nash equilibria exist in the game and that the price of anarchy can be O(n) in general,where n is the number of servers,due to undersupply problems. With specific topologies, we show that the price of anarchy can have tighter bounds. More importantly, with payments, servers are incentivized to replicate and the optimistic price of anarchy is always one. Non-cooperative caching is a more realistic model than cooperative caching in the competitive Internet, hence this work is an important step toward viable federated caching systems.