面向多业务需求的NFV和SDN融合的资源优化算法

Resource optimization algorithm of combination of NFV and SDN for application of multiple services

物联网的多种业务需要灵活的网络部署来保障其服务质量。针对物联网服务功能链部署问题,将网络功能虚拟化(NFV, network function virtualization)与软件定义网络(SDN, software defined networking)相结合,综合考虑转发成本以及流量平衡情况,给出了虚拟网络功能放置与服务功能链路由的联合优化模型,该优化模型是NP-Hard问题。为了求解该问题,提出两种启发式算法:一种是先路由后放置(FRTP, first routing then placing)的服务链部署算法,另一种是基于节点优先级的先放置后路由(PFBR, placing followed by routing)的服务链部署算法。仿真结果表明,与其他算法相比,提出的FRTP和PFBR算法能显著平衡网络中的流量负载,改善链路拥塞情况,从而提高服务功能链请求接受率。

Various services of internet of things （IoT） require flexible network deployment to guarantee different quality of service （QoS）. Aiming at the problem of IoT service function chain deployment, network function virtualization （NFV） and software defined networking （SDN） were combined to optimize resources. Considering forwarding cost and traffic load balance, a joint optimization model of virtual network function placement and service function chain routing was given and was proved to be NP-Hard. In order to solve this model, two heuristic algorithms were proposed. One was the service chain deployment algorithm of first routing then placing （FRTP） and the other was the placing followed by routing （PFBR） based on node priority. Simulation results demonstrate that FRTP and PFBR algorithm can significantly balance network traffic load while alleviating congestion and improving the acceptance ratio of the chain requests compared with other algorithms.