Service Function Chain Deployment Based on Candidate Paths

Network Function Virtualization (NFV) can help telecom operators to decouple Service Functions (SFs) from specific hardware. Service Function Chains (SFCs) consisting of Virtual Network Functions (VNFs) need to be deployed at various network locations to meet different service requests. However, how to deploy SFCs in operator networks with jointly optimizing bandwidth and computing resource utilization is still an open problem. Therefore, this paper proposes a Candidate Paths Based SFC Deployment (CPBSD) algorithm. In the CPBSD algorithm, we first design a Candidate Paths Generation (CPG) method to generate the candidate path sets between each pair of nodes. Then, using the generated candidate path sets, we formulate the joint optimization problem as a Binary Integer Programming (BIP). Further, we demonstrate that the BIP can be relaxed to a Linear Programming (LP) under some reasonable preconditions. Finally, the solution of optimization problem is obtained by solving the LP. Simulation results show that our CPBSD algorithm saves 16.9% resource utilization compared to the existing algorithms.