Crosstalk aware light-path selection in optical wdm/dwdm networks

Physical layer impairments are the major limitation for the high speed optical WDM/DWDM networks. They significantly affect the signal quality resulting poor quality of transmission which is normally expressed in terms of bit-error rate. To cope of with the future demand, increase in the no of channels and data speed further enhances these impairments. Hence new techniques are needed, which mitigate these impairments and ensure a better quality of transmission. Among the physical layer impairments we have studied the impact of in-band crosstalk on transmission performance of a transparent WDM/DWDM network. Error probabilities and power penalties produced by crosstalk are also investigated. As traditional RWA scheme pays a little regard to the physical layer impairments and cannot provide optimized network performance in practical networks, we have proposed a novel BER constrained, FWM aware RWA algorithm. The performance of the proposed algorithm is demonstrated through simulation and the results show that our algorithm not only gives a guaranteed quality of transmission but also improves the network performance in terms of blocking probability

Quality of service estimation techniques for an optical virtual private network over wdm/dwdm network

Quality of Service (QoS) in optical virtual private network (OVPN) is a demanding factor for communication network application. To provide desired QoS, the control plane in an all optical network (AON) has to be designed to maximize the quality of an OVPN connections (OVPNC). The AON is generally characterized by various network and physical layer parameters, which are used by the OVPN control manager (OVPNCM) for the estimation of quality factor (Q-Factor) for a set of possible OVPNC. It is observed that, not only the network layer parameters, but also the physical layer parameters called as physical layer impairments (PLIs) have impact on connection quality. In optical networks, the PLIs are incurred by non-ideal optical transmission media and accumulate along the optical connection. The overall effect of PLIs can be analyzed to determine the feasibility of quality based OVPNC. It is important to understand the process and provide the network as well as the PLI information to the OVPNCM and use this information efficiently to compute feasible connections along with Q-Factor values. Based on these, four different QoS estimation techniques have been proposed here