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.