Routing scheme of a multi-state computer network employing a retransmission mechanism within a time threshold

Because of packet unreliability, retransmission mechanisms are typically used to ensure data transmission at the sink without incurring data loss. Many application protocols have been developed on the basis of retransmission mechanisms. The multipath transmission control protocol guarantees quality of service (QoS) and reduces data transmission time in modern computer networks. A computer network that employs a retransmission mechanism can be called a multi-state computer network with a retransmission mechanism (MSCNR), because communication lines used by such a network can experience different states such as failure, partial failure, and maintenance. This study firstly evaluates the network reliability of a MSCNR for transmitting data d successfully through multiple minimal paths (MPs) within a time threshold T. An algorithm is proposed for generating all lower boundary vectors (LBVs) that can satisfy a time threshold. Then, the network reliability is computed in terms of all LBVs for (d, T) using the recursive sum of disjoint products algorithm. Furthermore, a routing scheme with spare MPs is adopted to reinforce the system reliability (referred to as the spare reliability). The spare reliability can also be easily computed by the proposed procedure.