To solve the problem that Multicast Request flows(MRs)need to traverse sequentially a Service Function Tree(SFT)consisting of Virtual Network Functions(VNFs)as well as ensuring stringent delay and jitter constraints of SFT in Network Function Virtualization(NFV)-enabled Software-Defined Networks(SDNs),a routing algorithm for constructing a multicast SFT based on depth-first search with an optimal link selection function is proposed.Firstly,the relative cost functions of network resources are proposed to guarantee the automatic load balancing of the network.Secondly,an Integer Linear Programming model(ILP)for the SFT dynamic embedding is constructed by jointly considering network resources,VNF dynamic placement and delay and jitter constraints of a multicast flow.Finally,for this NP-hard problem,an auxiliary edge-weight graph and optimal link selection function are designed for routing path selection,and a delay and jitter-aware SFT Embedding Algorithm(SFT-EA)is proposed with the objective of minimizing the resource consumption cost.Simulation results demonstrate the SFT-EA has better performance in terms of throughput,traffic acceptance rate,and network load balance.
关键词
网络功能虚拟化/服务功能树/多播/延迟和抖动
Key words
Network Function Virtualization(NFV)/Service Function Tree(SFT)/Multicast/Delay and Jitter
维普
万方数据