Before revision:  In this paper, we consider timer-based (TTL) policies across a cache network, where contents have differentiated timers over which we optimize. Each content is associated with a utility measured in terms of the corresponding hit probability. We start our analysis from a linear cache network: we propose a utility maximization problem where the objective is to maximize the sum of utilities and a cost minimization problem where the objective is to minimize the content transmission cost across the network .
After revision:  In this paper, we consider timer-based (TTL) policies . We propose provably optimal distributed algorithms that operate at each network cache to maximize the sum of utilities and a cost minimization problem where the objective is to minimize the content transmission cost across the network .