Performance and fault-tolerance analysis of a replicated HLR placement strategy in a broadband signaling transport network

We study the performance and fault-tolerance of a replicated home location register (HLR) placement strategy for the next generation broadband signaling transport network. Results show that the communication overhead is a key parameter that impacts the performance when the degree of replication is increased. To characterize the performance of the replicated HLR architecture in the presence of failures, we investigated two measure, namely, the system power and the lost potential. The system power is defined as the ratio of the total database throughput to the mean request response time while the lost potential is defined as the product of the mean request response time and the mean number of requests that are lost due to database failures. Results based on a subset of the model parameters indicate that a moderate degree of replication (around 5-10) can be supported to achieve the desirable QoS/fault-tolerance tradeoff under the particular type of query and update traffic considered in this study.