IEEE/OSA Journal of Optical Communications and Networking

Compared with traditional WDM networks, orthogonal frequency-division multiplexing (OFDM)-based flexible optical networks are able to provide better spectral efficiency due to their flexible allocation of requests on fine granularity subcarriers. Survivability is a crucial issue in OFDM-based flexible optical networks. In this paper, we present a survivable multipath provisioning scheme that provi... View full abstract»

We propose and experimentally demonstrate upstream transmission in a wavelength division multiplexing/optical code division multiplexing (WDM/OCDM) passive optical network (PON) without using any high-cost devices such as mode-locked lasers or LiNbO3 external modulators. To make optical network units (ONUs) simple, a loop-back transmission of short optical pulses for OCDM in upstream tr... View full abstract»

We propose an automatic wavelength control method using Rayleigh backscattering in a feeder fiber for tunable lasers employed in a wavelength-division multiplexing passive optical network. We demonstrate two realization methods, maximizing backscattered power and maximizing the second harmonic component with wavelength modulation. We analyze their limiting factors and impacts on the system perform... View full abstract»

Optical networks that support mixed line rates can accommodate diverse connection requests without the need for traffic grooming by assigning the appropriate line rates to match the bandwidth requirements of requests. Higher line rates offer the advantage of a lower per-unit cost of transmission but may suffer from more impairments compared to lower line rates. These impairments result in shorter ... View full abstract»

A capital expenditure model is a key requirement to evaluate multilayer (ML) metro and core network architectures. Based on the Internet protocol/multiprotocol label switching (IP/MPLS), MPLS-transport profile, optical transport network and WDM technology, a detailed capital expenditure model developed by researchers from system vendors and network operators is introduced. Besides current equipmen... View full abstract»

Rising energy costs and climate change have led to an increased concern for energy efficiency (EE). As information and communication technology is responsible for about 4% of total energy consumption worldwide, it is essential to devise policies aimed at reducing it. In this paper, we propose a routing and scheduling algorithm for a cloud architecture that targets minimal total energy consumption ... View full abstract»

Quality-of-service (QoS) support in Ethernet passive optical networks is a crucial concern. We propose a new dynamic bandwidth allocation (DBA) algorithm for service differentiation that meets the service-level agreements (SLAs) of the users. The proposed delay-aware (DA) online DBA algorithm provides constant and predictable average packet delay and reduced delay variation for the high- and mediu... View full abstract»

We present a flexible multichannel resource allocation mechanism for 60 GHz radio-over-fiber local access networks. The proposed mechanism is based on the structure of medium-transparent MAC, which is capable of allocating capacity dynamically over both optical and wireless media. A frequency band dedicated to the control channel is assigned to reduce the negative effects of the fiber delay in the... View full abstract»