  Blockchains enables tamper-proof, ordered logging for transactional data in a
decentralized manner over open-access, overlay peer-to-peer networks. In this
paper, we propose a decentralized framework of proactive caching in a
hierarchical wireless network based on blockchains. We employ the
blockchain-based smart contracts to construct an autonomous content caching
market. In the market, the cache helpers are able to autonomously adapt their
caching strategies according to the market statistics obtained from the
blockchain, and the truthfulness of trustless nodes are financially enforced by
smart contract terms. Further, we propose an incentive-compatible consensus
mechanism based on proof-of-stake to financially encourage the cache helpers to
stay active in service. We model the interaction between the cache helpers and
the content providers as a Chinese restaurant game. Based on the theoretical
analysis regarding the Nash equilibrium of the game, we propose a decentralized
strategy-searching algorithm using sequential best response. The simulation
results demonstrate both the efficiency and reliability of the proposed
equilibrium searching algorithm.
