An eagle's eye view of software defined network function virtualisation

Abstract

The operational and capital costs of diverse proprietary network appliances are increasing day by day. It is causing problems of network ossification for service providers. Service providers are under pressure to offer these network services while keeping operational and capital costs to the minimum. Network function virtualisation (NFV) is an open standard and non-proprietary based model that is witnessing significant development in replacing current vendor-specific and closed source implementations. NFV technology allows service providers to implement the software version of the middlebox on the commercial-off-the-shelf (COTS) server, called virtual network function (VNF). Software-defined networking (SDN) is another promising technology used to make the network flexible and programmable. When employed in conjunction with the SDN, NFV offers agile traffic steering, dynamic monitoring of VNFs, and centralised management at the control plane. The main motivation behind this work is to investigate NFV technology in-depth and explore SDN-controlled NFV architecture to make the network agile and flexible with minimum cost. In this paper, we attempt to discuss these technologies from the perspective of combining them to gain the maximum advantage of their amalgamation. We identified and discussed various research challenges that arise in combining SDN and NFV and their proposed solutions.