Simulation study of an optical burst switched agile all-photonic network

Abstract

Optical Burst Switching (OBS) is considered to enable bandwidth in the context of an Agile All-Photonic Network (AAPN). However, before deploying the OBS technique in the AAPN backbone, one must consider the best way to aggregate the variable length packets into burst of suitable size. Burst assembly mechanism can be timer-based, threshold-based and hybrid. In this work, we developed an analytical model, which models the probability distribution function of aggregation delays for different types of burst aggregation methods. The presented model is numerically evaluated using MATLAB code. The accuracy of the analytical model is verified by OpNet simulation. The impact of different types of burst aggregation methods and associated parameters (e.g. threshold-value and time-out value) on blocking probability and mean delays is also investigated. Another major concern in optical burst switched network is contention, which occurs when more than two bursts are destined to the same output port at the same time. In this thesis, a simple reservation approach, which copes completely with the packet losses associated with conventional OBS network and retains the simplicity of the core node, has been implemented in the context of AAPN architecture.