Feature Issue on Next-Generation WDM Network Design and Routing (WDMN). The increasing demand for bandwidth that has resulted from the emergence of various bandwidth-thirsty applications has increased the need for employing WDM as a dominant technology for the next-generation optical internet. As these networks carry gigantic amounts of information, survivability has become a primary and basic need for them. Although the available proactive protection schemes provide a 100% restoration guarantee, they require huge redundancy and usually result in a very high blocking probability. We propose a novel active restoration scheme that restores a failed primary lightpath based on multiple predefined but nonreserved backup paths along the primary path. Extensive simulation results based on three typical test networks indicate that with a small increase in restoration time, our new restoration scheme can reduce the blocking probability and the capacity requirement significantly while guaranteeing a very high restoration probability.
© 2004 Optical Society of AmericaPDF Article