Softwarization and virtualization in 5G mobile networks: Benefits, trends and challenges

The promise behind the effective deployment of 5G networks is an architecture able to provide flexibility, reconfigurability and programmability in order to support, with fine granularity, a wide and heterogeneous set of 5G use cases. This dictates a radical change in the design of mobile systems which, being usually based on the use of static deployment of vendor equipment characterized by monolithic functionality deployed at specific network locations, fail in providing the above mentioned features. By decoupling network functionalities from the underlying hardware, softwarization and virtualization are two disruptive paradigms considered to be at the basis of the design process of 5G networks. This paper analyses and summarizes the role of these two paradigms in enhancing the network architecture and functionalities of mobile systems. With this aim, we analyze several 5G application scenarios in order to derive and classify the requirements to be taken into account in the design process of 5G network. We provide an overview on the recent advances by standardization bodies in considering the role of softwarization and virtualization in the next-to-come mobile systems. We also survey the proposals in literature by underlining the recent proposals exploiting softwarization and virtualization for the network design and functionality implementation of 5G networks. Finally, we conclude the paper by suggesting a set of research challenges to be investigated.