Protection and Restoration for Wavelength division Multiplexing Optical Networks

Abstract

The growth of Wavelength Division Multiplexing (WDM) technologies has greatly improved the transmission ability of optical networks. The challenge with this network however is failure, which is caused by natural disasters such as earthquakes, hurricanes and floods. Consequently, network operators are no longer willing to deal with unprotected equipment, because optical networks are expected to tolerate failures, and be able to automatically re-route broken connections anytime and without central administration (restoration). Protection against link or node failure requires a proactive approach as it may lead to bandwidth loss. Protection schemes are considered the best mechanisms for fault tolerance in WDM optical networks. Existing schemes such as link and hybrid schemes require frequent improvement so as to combat the changing climate conditions. The main purpose of this research work is to design and implement novel protection and restoration resilience schemes for the enhancement of Quality of Service (Q0S) for WDM optical networks. Previous research implementation reports were based on the use of NS2 and OMNET design and implementation tools. The novel approach in this research work improves upon existing techniques by employing algorithmic design, modeling, and simulation approach of protection and restoration for WDM to improve the transmission ability in optical networks. This was achieved by the use of MATLAB R2012a and OPNET Modeler 14.0 as software implementation tools. The implementation for the algorithms was based on a random topology which consisted of subnets located within some cities in South Africa. The performance metrics used were backup resource ratio and blocking probability. The results obtained indicate that the novel restoration and protection routing algorithms have an improved performance when measured with the selected performance metrics (backup resource ratio and blocking probability), over the existing traditional routing algorithms. The significance of these results is the ability to improve the resilient failure nature that is common to network functionality.