Andreades, P;
Zervas, G;
(2020)
Parallel Modular Scheduler Design for Clos Switches in Optical Data Center Networks.
Journal of Lightwave Technology
, 38
(13)
pp. 3506-3518.
10.1109/JLT.2019.2963160.
Preview |
Text
Scheduler_Hardware_Implementation_forScalable_Optical_Packet_Switching_inData_Centre_Networks.pdf - Accepted Version Download (2MB) | Preview |
Abstract
As data centers enter the exascale computing era, the traffic exchanged between internal network nodes, increases exponentially. Optical networking is an attractive solution to deliver the high capacity, low latency, and scalable interconnection needed. Among other switching methods, packet switching is particularly interesting as it can be widely deployed in the network to handle rapidly-changing traffic of arbitrary size. Nanosecond-reconfigurable photonic integrated switch fabrics, built as multi-stage architectures such as the Clos network, are key enablers to scalable packet switching. However, the accompanying control plane needs to also operate on packet timescales. Designing a central scheduler, to control an optical packet switch in nanoseconds, presents a challenge especially as the switch size increases. To this end, we present a highly-parallel, modular scheduler design for Clos switches along with a proposed routing scheme to enable nanosecond scalable scheduling. We synthesize our scheduler as an application-specific integrated circuit (ASIC) and demonstrate scaling to a 256 × 256 size with an ultra-low scheduling delay of only 6.0 ns. In a cycle-accurate rack-scale network emulation, for this switch size, we show a minimum end-to-end latency of 30.8 ns and maintain nanosecond average latency up to 80% of input traffic load. We achieve zero packet loss and short-tailed packet latency distributions for all traffic loads and switch sizes. Our work is compared to state-of-the-art optical switches, in terms of scheduling delay, packet latency, and switch throughput.
| Type: | Article |
|---|---|
| Title: | Parallel Modular Scheduler Design for Clos Switches in Optical Data Center Networks |
| Open access status: | An open access version is available from UCL Discovery |
| DOI: | 10.1109/JLT.2019.2963160 |
| Publisher version: | https://doi.org/10.1109/JLT.2019.2963160 |
| Language: | English |
| Additional information: | This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions. |
| Keywords: | Clos-network switch , optical packet switching , optical interconnects , switch scheduling |
| UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Electronic and Electrical Eng |
| URI: | https://discovery.ucl.ac.uk/id/eprint/10106997 |
Archive Staff Only
 |
View Item |
