Improving TCP Performance Over Optical Burst-Switched (OBS) Networks Using Forward Segment Redundancy
Random contentions occur in Optical Burst-Switched (OBS) networks because of one-way signaling and lack of optical buffers. These contentions can occur at low loads and are not necessarily an indication of congestion. The loss caused by them, however, causes TCP at the transport layer to reduce its send rate drastically, which is unnecessary and reduces overall performance. In this paper, the authors propose forward segment redundancy (FSR), a proactive technique to prevent data loss during random contentions in the optical core. With FSR, redundant TCP segments are appended to each burst at the edge and Redundant Burst Segmentation (RBS) is implemented in the core so that when a contention occurs, primarily redundant data is dropped.