Virtual topology optimization for optical traffic grooming in OBS networks

In this paper, we address the problem of optical grooming of data bursts in segment-based traffic of Optical Burst Switching (OBS) networks. The objective is to aggregate in one burst, different overlapping sub-bursts that are transmitted to the same destination. This process is executed at the core node and is based on the availability of Virtual Optical Memory (VOM©) resources. Hence, it can improve bandwidth utilization on the optical fiber. A crucial issue in optical grooming is efficient routing and wavelength assignment problem that depend on an optimized design of optical virtual topology. This problem has been extensively treated in circuit based WDM networks, but not the context OBS networks. In this paper we develop an optimization algorithm for virtual topology construction tacking in consideration burst grooming process. A performances study was performed by evaluating traffic demand satisfaction rate, Burst blocking, and average transmission delay according to wavelength availability and the VOM© characteristics.