Flexible Virtual Routing Function Deployment in NFV Based Network with Minimum Total Network Cost

摘要

In a conventional network, most network devices, such as routers, are dedicated devices that do nothave much variation in capacity. In recent years, a new concept of Network FunctionsVirtualisation (NFV) has come into use. The intention is to implement a variety of network functionswith software on general-purpose servers and this allows the network operator to select anycapabilities and locations of network functions without any physical constraints.This paper focuses on the deployment of NFV-based routing functions which are one of criticalvirtual network functions, and present the algorithm of virtual routing function allocation thatminimize the total network cost. In addition, this paper presents the useful allocation policy ofvirtual routing functions, based on an evaluation with a ladder-shaped network model. This policytakes the ratio of the cost of a routing function to that of a circuit and traffic distribution in thenetwork into consideration. Furthermore, this paper shows that there are cases where the use ofNFV-based routing functions makes it possible to reduce the total network cost dramatically, incomparison to a conventional network, in which it is not economically viable to distribute smallcapacityrouting functions.