Network Function Virtualization

Preface

Because of the emergence of user‐friendly smartphones and the advances in cellular data network technologies, the volume of data traffic carried by cellular networks has been experiencing a phenomenal rise. One large cellular operator has reported a growth of 8000% of cellular data traffic over the past 4 years [1], and it grows to 10.8 exabytes/month by 2016, an 18‐fold increase over 2011.

To meet the constantly increasing traffic demands while maintaining or improving average revenue per user (ARPU), operators are always seeking new ways to reduce their operational expenditure (OPEX) and capital expenditure (CAPEX). One way to improve the cost‐effectiveness of infrastructure is to introduce the concepts of scalable infrastructure and elastic capacity on demand, using virtualization and cloud computing, which have become the cornerstones of many successful large‐scale IT infrastructure management.

Thanks to their successful deployment in Internet companies such as Google and Amazon, emerging cloud computing technologies have started to be borrowed and deployed in the telecom network, in the form of software‐defined networking (SDN) and network functions virtualization (NFV). The SDN design introduces a separation between the control and forwarding components of the network. Among the use cases of such architecture are the access/aggregation domain of carrier‐grade networks, mobile backhaul, cloud computing, and multilayer (e.g., Internet Protocol (IP), Ethernet, Optical Transmission ...