NegotiaToR: Towards A Simple Yet Effective On-demand Reconfigurable Datacenter Network

TL;DR

NegotiaToR is a simple, reconfigurable optical datacenter network architecture that uses on-demand scheduling to improve flow completion times and throughput, especially under heavy loads.

Contribution

It introduces a minimalist, on-demand reconfigurable DCN design compatible with flat topologies, optimizing for incasts and bypassing scheduling delays.

Findings

Achieves small mice flow FCT and high goodput in simulations.

Outperforms state-of-the-art traffic-oblivious designs in mice flow FCT.

Effective under heavy traffic loads.

Abstract

Recent advances in fast optical switching technology show promise in meeting the high goodput and low latency requirements of datacenter networks (DCN). We present NegotiaToR, a simple network architecture for optical reconfigurable DCNs that utilizes on-demand scheduling to handle dynamic traffic. In NegotiaToR, racks exchange scheduling messages through an in-band control plane and distributedly calculate non-conflicting paths from binary traffic demand information. Optimized for incasts, it also provides opportunities to bypass scheduling delays. NegotiaToR is compatible with prevalent flat topologies, and is tailored towards a minimalist design for on-demand reconfigurable DCNs, enhancing practicality. Through large-scale simulations, we show that NegotiaToR achieves both small mice flow completion time (FCT) and high goodput on two representative flat topologies, especially under heavy loads. Particularly, the FCT of mice flows is one to two orders of magnitude better than the state-of-the-art traffic-oblivious reconfigurable DCN design.