Resource Allocation Methods Considering Residual Link Bandwidth for Service Function Chaining Design

Service chaining composed of several different virtual network functions (VNFs) constitutes a use case of Network Functions Virtualization (NFV). In a conventional method, the optimal allocation of VNFs and logical paths was resolved by using integer linear programming. However, because the approach did not consider that the required resources of each service differ, the residual resources of the links or physical machines were dispersed as the number of allocated services increased. Therefore, the method did not efficiently allocate resources to services requiring many resources. In this paper, in order to accommodate such services, we propose novel resource allocation methods that consider the residual link bandwidth. We evaluated the performance of the proposed methods through a simulation. The results show that our methods can allocate resources to services requiring many resources more efficiently than can conventional methods.