LAUSR

Multiaccess edge computing (MEC) allows terminal devices (TDs) with limited energy and computing capabilities to offload tasks to edge servers, which have more energy and computing capabilities to provide better service. In order to accommodate more users, an edge server can be divided into many virtual machines (VMs), but the interference among VMs could cause decreased service quality. At the same time, due to server hardware and software errors, there are random temporary failures regardless of whether a virtual machine is serving or not. This article uses a multidimensional Markov chain to establish a unified performance analysis model that jointly considers multiple types of terminals, different local service capabilities, different request arrival traffic, different virtual machine numbers, and different virtual machine failure rates. The statistical models of access blocking probability, resource availability, capacity, forced dropping probability, and retainability are presented. Furthermore, we analyze whether and how the local service should be performed when the virtual machine used fails and propose a backward offloading scheme. Analysis results show that some of quality is not monotonous. The model in this article provides a powerful and accurate analytical method for the preperformance simulation of actual engineering design.