A stochastic node-failure network with individual tolerable error rate at multiple sinks

Many enterprises consider several criteria during data transmission such as availability, delay, loss, and out-of-order packets from the service level agreements (SLAs) point of view. Hence internet service providers and customers are gradually focusing on tolerable error rate in transmission process. The internet service provider should provide the specific demand and keep a certain transmission error rate by their SLAs to each customer. This paper is mainly to evaluate the system reliability that the demand can be fulfilled under the tolerable error rate at all sinks by addressing a stochastic node-failure network (SNFN), in which each component (edge or node) has several capacities and a transmission error rate. An efficient algorithm is first proposed to generate all lower boundary points, the minimal capacity vectors satisfying demand and tolerable error rate for all sinks. Then the system reliability can be computed in terms of such points by applying recursive sum of disjoint products. A benchmark network and a practical network in the United States are demonstrated to illustrate the utility of the proposed algorithm. The computational complexity of the proposed algorithm is also analyzed.     

Reliability assessment of a stochastic node-failure network with multiple sinks under tolerable error rate

Internet service providers and enterprise customers are increasingly focusing on the tolerable error rate during transmission. This has high significance especially in service-level agreements. This study concentrates on a stochastic node-failure network (SNFN) with multiple sinks, where each component (arc or node) has several possible capacities and a transmission error rate. Measuring the performance level for an SNFN is an important issue in the system-design and system diagnosis phases. This study evaluates the system reliability of a network, or the probability that the demand is fulfilled under the tolerable error rate. In terms of minimal paths, we propose an efficient algorithm to find all minimal capacity vectors, and then compute the system reliability in terms of all minimal capacity vectors using the recursive sum of disjoint products algorithm. Finally, we test the proposed algorithm for a benchmark network and two practical networks.     

Reliability evaluation for a manufacturing network with multiple production lines

This paper focuses on performance evaluation of a manufacturing system with multiple production lines based on the network-analysis perspective. Due to failure, partial failure, or maintenance, the capacity of each machine is stochastic (i.e., multi-state). Hence, the manufacturing system can be constructed as a stochastic-flow network, named manufacturing network herein. This paper intends to measure the probability that the manufacturing network can satisfy customers’ orders. Such a probability is referred to as the system reliability. A graphical representation is first proposed to transform a manufacturing system into a manufacturing network. Thereafter, we decompose the manufacturing network into general processing paths and reworking paths. Three algorithms are subsequently developed for different scenarios and multiple production lines to generate the minimal capacity vectors that machines should provide to satisfy demand. The system reliability can be derived in terms of such capacity vectors afterwards.     

Backup reliability of stochastic imperfect-node computer networks subject to packet accuracy rate and time constraints

In a real-time computer network, arcs and nodes have multi-state capacity, lead time, and packet accuracy rate (PAR). Evaluating the reliability of a network whose nodes are imperfect is complex, because node failure results in the disablement of adjacent arcs. Such a network is named a stochastic imperfect-node computer network (SINCN). Under the strict assumption that each arc has a deterministic capacity, the quickest path problem is to find a path that sends a specific amount of data with minimum transmission time. Subject to both an assured PAR and time constraints, this paper proposes an efficient algorithm to evaluate the system reliability of an SINCN. Furthermore, a routing scheme is adopted to reinforce the system reliability. Accordingly, reliability based on the routing scheme is calculated. An application of our method on the Taiwan academic network is described to show its impact on the backup reliability for different routing schemes.