Optimum protection architecture for reliable dense-WDM lightwave networks

This paper examines reliable and economical wavelength-division-multiplexed trunk-network protection architectures. Protection architectures for lightwave networks are classified as path/link switching type or dedicated/shared standby-resources type. The required number of optical links for each protection-architecture is calculated and compared in terms of the number of wavelengths, demand patterns, and several network topologies. The results show that the path-dedicated protection architecture, which enables fast protection, is pretty cost-effective for a typical regional network when the number of wavelengths is more than ten. Dense-WDM technologies will replace the economical and reliable protection-architecture from the ordinary link-shared protection to the path-dedicated protection.