Holistic Roadmap of Trends in Radio Access Network Slicing: A Survey

Over the years, radio access network (RAN) slicing has been perceived to facilitate resource sharing in fifth generation (5G) wireless networks. Resource allocation particularly deals with efficiently subleasing and assigning resources to satisfy the demand of customers. Resource trading, on the other hand, creates a lucrative marketplace for exchanging scarce radio resources for remuneration by designing innovative incentive mechanisms for profit maximization. The constant expansion in network capacity has reiterated the need for groundbreaking approaches to achieve sustainability while increasing profits and resource utilization efficiency. However, the existing RAN slicing paradigm is faced with several challenges involved with security issues in the open network environment. This article provides an overview of the trends in RAN slicing research with a focus on its technical, trading, and security aspects. Specifically, several algorithms proposed in RAN slicing research to solve the allocation, trading, and security issues are discussed. Then we present various critical challenges existing in resource sharing, as well as new research directions that may uncover novel techniques in the 5G and beyond paradigms. With this survey, we provide a blueprint to guide future research in RAN slicing.