MULTIPLE-STAR WAVELENGTH-ROUTER NETWORK AND ITS PROTECTION STRATEGY

A wavelength division multiplexed (WDM) multiple-star network and its accompanying path and router protection strategies are proposed for in terconnecting N major snitch nodes in a national-scale telecommunicati ons network. For a single path failure and uniform traffic matrix, fib er requirements are shown to be less than for a WDM ring, while provid ing greater resilience to multiple path failures. ''Adding'' and ''dro pping'' only whole wavelength channels between node pairs is found to lead to severe design instabilities and overinvestment in fiber, and t imesharing of wavelength channels is recommended to minimize fiber qua ntities. A star network capable of interconnecting N = 22 switch nodes and an all-optical path protection switching method are verified expe rimentally, using a 16-channel 2.5-Gbit/s WDM system and a 22 x 22-por t bulk-optics wavelength multiplexer as the hub router. Protection swi tching speeds within 50 ms are projected for a national-scale network.