Asynchronous Transmission Strategy and Optical IntraCluster Connectivity for Hyperscale Data Centers

As the optical devices technology constantly provides upgraded capabilities for higher optical fiber bandwidth utilization, achieving high data rates, the request for effective medium access control (MAC) algorithms to exploit the available fiber bandwidth in optical networking arises as very critical. Also, as the channels data rate in an optical fiber is getting higher, the synchronization among the transmissions is getting harder to be achieved. For this reason, asynchronous transmission access strategies gradually gain ground in the optical domain. In this study, we explore the performance of a distributed asynchronous transmission wavelength division multiple access (WDMA) strategy along with an efficient wavelengths adjustment scheme, for optical intra-cluster data center networks (DCNs). Our proposal reaches different levels of performance according to the adopted wavelengths adjustment scheme, while in all cases it achieves improved performance comparing to other intra-cluster DCNs. Finally, the proposed intra-cluster network is proven to be power efficient, suitable to be exploited in hyperscale DCNs.

I. Introduction

The continuously expanding bandwidth-thirsty cloud services, like high definition real-time video streaming, search engines, social networking, Internet of Things (IoT) etc. have form a data-intensive environment in conventional data centers (DCs). The big data industry predict a tremendously increasing traffic in the existing DC networks (DCNs) the following years. In specific, Intel foresees that hyperscale DCs infrastructures will deploy almost 80% of its computing and storage systems by 2025 [1]. Also, Google is working towards to sufficiently serve the bandwidth demand that doubles every 12–15 months in its DCs [2]. Finally, Cisco ascertains that more than 70% of its DCN traffic is internally consumed within the DCN [3].