Improving Performance of Optical Networks by a Probable Approach

Abstract

Abstract Optical Burst Switching (OBS) networks are new emerging techniques that alternate Optical Circuit Switching (OCS) and Optical Packet Switching (OPS) techniques. The high bandwidth of fiber links in these networks, besides WDM (Wavelength Division Multiplexing) helps the Internet to handle the heavy traffic. OBS networks have an important issue that needs to be tackled. These networks are bufferless in their nature, so when two bursts are trying to reserve one wavelength one of them is dropped. This drop can be assumed as an indicator of congestion; as a result, the sending rate will be decreased, despite the fact that the network may not be congested. So, wired protocols like TCP (Transmission Control Protocol) cannot work to their high potential in OBS networks. In this paper, we propose a new scheme based on a probable approach that can distinguish burst drops caused by contentions from burst drops caused by contention, so we can improve the performance of the network. Extensive simulative studies show that the proposed algorithm outperforms TCP Vegas in terms of throughput and packet delivery count.