In this paper, we address the issue of efficiently allocating wavelengths to communication requests in wavelength division multiplexing (WDM) optical networks. We present a simple greedy algorithm and study its performance on directed binary fiber trees. We prove that our algorithm guarrantees a 5=3-approximationfor wavelengths assignment in binary tree shaped WDM optical networks. We also prov...

This paper discusses survivable routing for Wavelength Division Multiplexing (WDM) networks. The downside of boosting network capacity through a technology like WDM is increasing network vulnerability. With more than one network operator in South Africa network survivability will be one of the most important and challenging quality of service (QoS) criteria. This paper investigates new network ...

Wavelength-division-multiplexing (WDM) networks with wide channel grids and bandwidths are promising for low-cost, low-power optical interconnects. Wide-bandwidth, single-band (i.e., no free-spectral range) add-drop filters have been developed on silicon using anti-reflection contra-directional couplers with out-of-phase Bragg gratings. Using such filter components, we demonstrate a 4-channel, ...

Erbium-doped fiber amplifiers ~EDFAs! have been intensively studied for wavelength-division-multiplexing ~WDM! communication systems. The stabilization of the amplifier gain against the input signal-power variation is one of the key issues for WDM networks. The gainstabilizing technique using a passive optical feedback device, such as a bandpass filter or a fiber Bragg grating, has been reporte...

With the rise in demand for channel capacity, Wavelength Division Multiplexing (WDM) technique is employed in optical communication networks. Gain Flattened Erbium Doped Fiber Amplifier (EDFA) is used in optical WDM system to obtain a uniform output power level. The performance of EDFA depends on various parameters such as fiber length, pump power, pumping wavelength and pumping technique. The ...

WDM (wavelength division multiplexing) appears to be the solution of choice for providing a faster networking infrastructure that can meet the explosive growth of the Internet. It has the scalability problem with increasing the access node numbers in WDM ring architecture, so we further propose the alternatives of hierarchical WDM ring architecture. Since the traditional IP provides the best ef...

The performance of optical components such as photonic switch, OXC, Optical Amplifiers is degraded by the presence of Non-linear effects in Optical networks. Four-wave Mixing (FWM) is the main deteriorating factor in WDM (Wavelength Division Multiplexing) Optical Network. It is necessary to study the impact of FWM on the performance of WDM networks. In this paper, we study the effects of FWM al...

In order to implement flexibility as well as survivable capacities over passive optical network (PON), a new automatic random fault-recovery mechanism with array-waveguide-grating based (AWG-based) optical switch (OSW) is presented. Firstly, wavelength-division-multiplexing and optical code-division multiple-access (WDM/OCDMA) scheme are configured to meet the various geographical locations req...

In order to implement flexibility as well as survivable capacities over passive optical network (PON), a new automatic random fault-recovery mechanism with array-waveguide-grating based (AWG-based) optical switch (OSW) is presented. Firstly, wavelength-division-multiplexing and optical code-division multiple-access (WDM/OCDMA) scheme are configured to meet the various geographical locations req...

We describe the transmission characteristics of a wavelength independent wavelength division multiplexing passive optical network (WDM-PON) based on a wavelength channel data rewriter (WCDR). The WCDR is composed of a linear amplifier (LA) and a saturated semiconductor optical amplifier (SOA), and by using the WCDR in optical network units (ONUs), we can erase the downstream signal and modulate...