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In optical burst switching networks, wavelength converters (WCs) of core nodes are used to decrease the burst loss rate. The implementation of the WCs is difficult in the current technology and the cost of WCs is high. So some core nodes may be configured insufficient WCs to reduce the cost in OBS networks. However, many data channel scheduling algorithms do not count the number of WCs and the performance of burst loss rate is not good in the condition of insufficient WCs. To overcome the defect, two novel batch scheduling algorithm with insufficiency of WC are proposed in this paper. The former algorithm improves the WCs’ resource utilization probability to reduce the burst loss rate and the later algorithm saves the WCs’ resource for the incoming bursts to use to improve the burst loss performance. The later algorithm can reduce more burst loss rate with the same number of WCs, compared with the other scheduling algorithms. The simulation results show that the later algorithm is more effective in reducing the burst loss rate with insufficient WCs.

Wavelength converters for phase sensitive modulation formats based on semiconductor optical amplifiers are discussed. Advantages and limits are discussed based on an actual implementation.

This paper reviews the recent progress of quantum-dot semiconductor optical amplifiers developed as ultrawide-band high-power amplifiers, high-speed signal regenerators, and wideband wavelength converters.

A numerical model of wavelength converters based on cross-gain modulation in semiconductor optical amplifiers is developed. A more accurate gain coefficient model, spatial variations of carrier densities, and position-dependent differential gain and internal loss are included.

We develop a mathematical model of chirp in a Semiconductor Optical Amplifier (SOA)-based wavelength converters using cross-gain modulation (XGM).Using the model, we study numerically the effects that the chirp of Gaussian pluses and ultra-Gaussian pluses make into the optical signal pluses in Semiconductor Optical Amplifier (SOA), and theoretically analysis the parameters that affect chirp variations.

In this paper we review the current status of transparent networks and in particular of all-optical regenerators and wavelength converters that might be part of next generation telecommunication systems.

Cascaded (chi) (2 ) based wavelength conversions in quasi phase-matched periodically poled LiNbO 3 waveguide were theoretically analyzed by the step-by-step method. The analytic expressions were obtained and analyzed in detail to reveal the physical insight of the wavelength converters based on the cascaded (chi) (2 ) process. In addition, the phase shift of the converted light was studied using the obtained analytic expressions. Some of the simulated results were compared with our experimental results.

We analyzed the key design parameters of semiconductor optical amplifiers (SOAs) based wavelength converters. Simple analytical equations to calculate the rise and fall time of the converted signals in a long SOA (>5OOim) are derived.

In this paper, the importance of wavelength converter modules in all-optical networks is highlighted. Two types of wavelength converters are proposed, static and dynamic wavelength converters. A wavelength converter (also referred to as Frequency Transformer) converts the wavelength of the incoming optical signal to another wavelength in the wavelength spectrum. The goal of this work is to provide some insights into the effect of static versus dynamic wavelength conversion on the performance of optical networks based on Bidirectional de Bruijn (BdB) topology. We study how performance (in terms of blocking probability and the network load) depend on the number of wavelengths per optical link. We also evaluate performance of a given network employing both static and dynamic wavelength converters through simulation and present the simulation results. The motivation behind having static wavelength converters is the relatively low cost compared to dynamic wavelength converters. Also an Error-Correcting Routing Algorithm (ECRA) is proposed that makes use of static wavelength converters which is based on the principle of error-correcting routing.