Performance Analysis of an Optical Packet Switch Employing Full/Limited Range Share Per Node Wavelength Conversion

Abstract

Abstract-In this paper, we study an asynchronous optical packet switching node equipped with a number of limited range or full range wavelength converters shared per node. The packet traffic is realistically modeled by a superposition of a finite number of on-off sources as opposed to the traditional Poisson model which ignores the limited number of ports on a switch. We both study circular and non-circular limited range wavelength conversion schemes. In our simulations, we employ the far conversion policy where the optical packet is switched onto the farthest available wavelength in the tuning range, which is known to outperform the random conversion policy. We propose an approximate analytical method based on block tridiagonal Markov chains and fixed point iterations to solve for the blocking probabilities in share per node wavelength conversion systems. The method provides an accurate approximation for full range systems and acceptable results for limited range systems.

Wavelength allocation in an optical switch with a fiber delay line buffer and limited-range wavelength conversion

“…In case both potential gaps have the same value or if only one of the wavelengths is able to receive the packet, the evolution follows (1) and (2). If the next arriving packet has to be dropped due to the value of the horizons (both above ND) the evolution will follow the same equations already shown in this section, but using variableĨ n instead of I n to describe the time until the next accepted packet.…”

“…It must be noted that in those works, as well as here, we assume that whenever a conversion is required, a converter will be available to perform it. The case when there are fewer converters than wavelengths has been studied in [1,6] assuming full-range wavelength conversion and in [2,5,13] for the bufferless limited range wavelength conversion case. In the next section we present a model for the analysis of the case where the set of wavelengths is fixed and the wavelength is selected using the MinH or MinGap policies.…”

“…Furthermore, limitedrange wavelength conversion usually implies a more intricate interaction between adjacent wavelengths. This topic has been considered in [2,5,13] for the bufferless case relying on (approximate) analytical models. More precisely, for exponential packet sizes, the lack of buffers allows an exact solution for the full range conversion case.…”

Scheduling Based on Minimal Conversion Degree With Respect to Wavelength Conversion and Coding in Optical Multicast Node

“…Lastly, we evaluate the packet loss probability of the proposed CWCN by comparing with our previously reported node architecture TLWC and FRWC [10]. In [10], the full range wavelength converter is configured in SPN (share per node) mode.…”

Fixed point analysis of limited range share per node wavelength conversion in asynchronous optical packet switching systems

“…While doing so, we benefit from the block-tridiagonal structure of the generators that arise using a technique similar to one introduced in [13]. Second, we propose novel approximations to the fullness probability of the tuning range as an enhancement of the approximation proposed in [9] as well as in [14] to deal with limited range conversion. We combine these two methods to provide a new approximative technique for the performance analysis of switching systems using full or circular-type limited range SPN wavelength conversion.…”