Date Added: Jan 2010
Traffic grooming is important for optical transport networks. Most of studies in this area have focused on minimizing total network capacity or maximizing total served traffic demand subject to predefined network capacity. When planning lightpath demand, the existing traffic grooming studies often ignored the impairments in the physical layer. However, it is well-understood that an optical signal suffers from impairments in the physical layer, ranging from linear factors, such as ASE noise and residual dispersion, to nonlinear factors, such as self-phase modulation, cross-phase modulation, and four-wave mixing. These factors limit an optical signal to be transmitted a certain distance before 3R signal regeneration is necessary. Such a distance is called optical transparent reach limit.