Estimated link selection for DCLC problem

The development of the efficient quality of service (QoS) routing algorithms in a high speed network environment is very important and, at the same time, a very difficult task due to the need to provide divergent services with QoS requirements. The distributed adaptive routing is the typical routing algorithm that is used in the current Internet. If the parameter we concern is to measure the delay on that link, then the shortest path algorithm obtains the least delay (LD) path. Meanwhile, if the parameter is to measure the link cost, then the shortest path algorithm calculates the least cost (LC) path. The delay constrained least cost (DCLC) path problem has been shown to be NP-hard. The path cost of LD path is relatively more expensive than that of the LC path, and the path delay of LC path is relatively higher than that of the LD path in DCLC problem. In this paper, we investigate the performance of a heuristic algorithm, estimated link selection (ELS) for the DCLC problem with a new parameter which is a probabilistic combination of cost and delay. We have performed empirical evaluation that compares our proposed ELS with the DCUR in various network situations. It significantly contributes to identify the low cost and low delay unicasting path and the performance improvement is up to about 49% in terms of normalized surcharge.