Backup reliability assessment within tolerable packet error rate for a multi-state unreliable vertex computer network

From the viewpoint of quality of service, the packet error rate (PER) and delivery time are both of critical performance indicators to assess internet quality for supervisor and customers. A computer network is composed of Internet data centers and delivery mediums and we can regard it as a network topology with vertices and arcs. Virtually, each component (vertex or arc) has multiple capacities/states due to failure, maintenance, etc. Evaluating the reliability of a network with unreliable vertices is a difficult problem because of the disabled of adjacent arcs by vertex failure. Hence the network with unreliable vertices can be called a multi-state unreliable vertex computer network (MUVCN). Concentrating on the MUVCN, this paper addresses the data delivery from the source to the sink through k(k⩾2) disjoint minimal paths simultaneously, and proposes an algorithm to assess system reliability fulfilling demand constraint, tolerable PER, and time threshold. Furthermore, a routing strategy for raising system reliability is established in advance to specify the main and backup minimal paths. Subsequently, such a system reliability named the backup reliability can be computed faster.