  Reconfigurable intelligent surface has attracted the attention of academia
and industry as soon as it appears because it can flexibly manipulate the
electromagnetic characteristics of wireless channel. Especially in the past one
or two years, RIS has been developing rapidly in academic research and industry
promotion and is one of the key candidate technologies for 5G-Advanced and 6G
networks. RIS can build a smart radio environment through its ability to
regulate radio wave transmission in a flexible way. The introduction of RIS may
create a new network paradigm, which brings new possibilities to the future
network, but also leads to many new challenges in the technological and
engineering applications. This paper first introduces the main aspects of RIS
enabled wireless communication network from a new perspective, and then focuses
on the key challenges faced by the introduction of RIS. This paper briefly
summarizes the main engineering application challenges faced by RIS networks,
and further analyzes and discusses several key technical challenges among of
them in depth, such as channel degradation, network coexistence, network
coexistence and network deployment, and proposes possible solutions.
