  As an important technology to ensure data security, consistency,
traceability, etc., blockchain has been increasingly used in Internet of Things
(IoT) applications. The integration of blockchain and edge computing can
further improve the resource utilization in terms of network, computing,
storage, and security. This paper aims to present a survey on the integration
of blockchain and edge computing. In particular, we first give an overview of
blockchain and edge computing. We then present a general architecture of an
integration of blockchain and edge computing system. We next study how to
utilize blockchain to benefit edge computing, as well as how to use edge
computing to benefit blockchain. We also discuss the issues brought by the
integration of blockchain and edge computing system and solutions from
perspectives of resource management, joint optimization, data management,
computation offloading and security mechanism. Finally, we analyze and
summarize the existing challenges posed by the integration of blockchain and
edge computing system and the potential solutions in the future.
