Data center networks are facing growing challenges to deliver higher bandwidth efficiency, lower latency, better flexibility, and lower cost. Various optical interconnect schemes have been proposed to take advantage of the high bandwidth capacity and low power consumption offered by optical switching. However, these schemes cannot offer flexible bandwidth sharing due to the large granularity in optical circuit switching, and they require costly optical components. In this paper, we introduce a novel data center network architecture based on cyclic arrayed waveguide grating device and multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing technology with parallel signal detection (PSD). This architecture offers flexible bandwidth resource sharing at fine granularity. Other features include high-speed switching, low and uniform latency, and the ability to change the data rates dynamically. By eliminating costly optical components and keeping the core optical router passive and static, the power consumption, hardware cost, and operation cost are reduced. The fine granularity bandwidth sharing and MIMO switching through PSD are verified experimentally. We also propose and evaluate efficient subcarrier allocation schemes to achieve high bandwidth utilization. Finally, we present the implementation of an efficient scheduler for the bandwidth allocation of the proposed scheme.

Design and Evaluation of a Flexible-Bandwidth OFDM-Based Intra-Data Center Interconnect

A novel passive optical network (PON) architecture based on optical orthogonal frequency division multiple access (OFDMA) technologies is presented. Two potential medium access control (MAC) methods namely dynamic circuit transmission and fixed burst transmission are investigated.

MAC Protocols for Optical Orthogonal Frequency Division Multiple Access (OFDMA)-based Passive Optical Networks

Motivated by the design goals of Global Environment for Network Innovation (GENI), we consider how to support the slicing of link bandwidth resources as well as the virtualization of optical access networks and optical backbone mesh networks. Specifically, in this paper, we study a novel programmable mechanism called optical orthogonal frequency division multiplexing (OFDM)/orthogonal frequency division multiple access (OFDMA) for link virtualization. Unlike conventional time division multiplexing (TDM)/time division multiple access (TDMA) and wavelength division multiplexing (WDM)/wavelength division multiple access (WDMA) methods, optical OFDM/OFDMA utilizes advanced digital signal processing (DSP), parallel signal detection (PSD), and flexible resource management schemes for subwavelength level multiplexing and grooming. Simulations as well as experiments are conducted to demonstrate performance improvements and system benefits including cost-reduction and service transparency.

PONIARD: A Programmable Optical Networking Infrastructure for Advanced Research and Development of Future Internet

PONIARD : A Programmable Optical Networking Infrastructure for Advanced Research and Development of Future Internet

Various types of passive optical networks operate simultaneously in one passive optical network system comprising an optical line terminal, a passive remote node, and multiple optical network units. Downstream data is orthogonal frequency division multiplexed onto a single wavelength optical carrier transmitted on a primary downstream optical beam from the optical line terminal to a splitter in the passive remote node. The primary downstream optical beam is split into multiple secondary downstream optical beams; each is transmitted to a specific optical network unit. Upstream data is orthogonal frequency division multiplexed onto a single wavelength optical carrier transmitted on a secondary upstream optical beam from each optical network unit to a coupler in the passive remote node. The upstream wavelength for each optical network unit is different. The wavelength division multiplexed optical beam is transmitted from the passive remote node to a parallel signal detector in the optical line terminal.

Orthogonal Frequency Division Multiple Access Based Virtual Passive Optical Network (VPON)

We demonstrate a novel WDM passive optical network (WDM-PON), which delivers data as well as video services to the end users through the employment of subcarrier modulation at the optical line terminal (OLT) and parallel signal detection (PSD) at the optical network unit (ONU). Experimental results show that the proposed WDM-PON is capable of providing triple play services in the access network.

P.N. Ji

Papers

WDM Passive Optical Network with Parallel Signal Detection for Video and Data Delivery