Abstract: Mobile edge computing(MEC) has emerged as a promising computing paradigm to solve the conflict between the growing number of latency-sensitive applications and user demands and the constrained computing resources.To provide users with a more efficient and scalability service function chain(SFC) to satisfy users’ requests by deploying virtual network functions(VNF) in the edge environment.Unreliable service or serious service failure in the process of providing service may lead to great loss to users,so the network service provider must ensure the provision of constant and reliable service.Considering the reliability of edge servers for this problem,the gate recurrent unit(GRU) supported by computational unified device architecture(CUDA) is used to predict the availability of VNF,and the VNF instances are backed up in advance through the prediction results,avoiding the problem of excessive cost caused by over-redundant backups.The storage resources of the servers are limited,and VNF instance availability placement(RVP) algorithm is proposed to optimize the cost of service providers.Finally,performance evaluation is performed,and the experimental results show the excellence of the proposed RVP algorithm.

Key words: Edge computing, Service function chain, Virtual network function, Reliability, VNF instance placement