We investigate the advantages and disadvantages of different loopback buffer architectures for optical switches and compare their performance via simulation. The simulation results show that, without the use of virtual output queuing, the head-of-line blocking can be alleviated by wavelength parallelism when each separate queue in a loopback buffer has multiple transmitters. Furthermore, the proposed two-level flow control can eliminate packet drop at the switch, resolve rate mismatching due to output queuing at switch outputs, and ensure that congestion occurring at the hotspot port will not affect the performance of non-congested ports.
© 2011 OSA
Optics in the Data Center
Original Manuscript: April 29, 2011
Revised Manuscript: June 29, 2011
Manuscript Accepted: June 30, 2011
Published: July 25, 2011
Xiaohui Ye, Roberto Proietti, Yawei Yin, S. J. B. Yoo, and Venkatesh Akella, "Buffering and Flow Control in Optical Switches for High Performance Computing," J. Opt. Commun. Netw. 3, A59-A72 (2011)