 as high definition (HD) videos, virtual reality (VR), augmented reality (AR), and fixed mobile convergence (FMC). URLLC focuses on latency-sensitive services, such as self-driving cars, remote surgery, or drone control. Lastly, mMTC focuses on services that have high require- ments for connection density, such as those typical for smart city and smart agriculture use cases. Moreover, 5G is expected to support diverse and unprecedented vertical segments, including factories, oil, gas and energy, utilities and public safety, etc. These vertical services present quite different requirements in terms of reliability, data rate, latency, deployment density, and mobility [2]. All these vertical services and requirements require the 5G system to be flexible and agile [3]. The diverse services onto operators' networks expand the reach of operators' business and open new sources of revenue to service providers and mobile operators. Network slicing, as one of the key technologies in 5G, allows network operators to define logical networks on top of the single infrastructure to adapt to specific requirements and ser- vice level agreement (SLA) [4]. It can facilitate the support of vertical segments with lower operating expense (OpEx), greater capital expenditure (CapEx) efficiency, fast deployment, and short time-to-market [5]. As an integral part of end-end network slice, radio access net- work (RAN) support of network slice is essential to empower the diverse vertical services, and can provide customized differentiation toward different slice requirements. But due to scarcity of spectrum, RAN slicing shares spectrum which is significantly different from core network (CN) slicing in which to decouple the user from the control plane, places the control plane on a logical centralized location, and exposes state and abstract resources to applications and tenants. In RAN slicing, several of the complex functions executed in base stations are tightly coupled with the hardware SO as to achieve the desired performance. Therefore, 