Survivability in waveband switching optical networks: Challenges and new ideas

Abstract

With the developmental trend of ultra-high speed and ultra-large capacity required in optical networks, the number of wavelengths in each fiber greatly keeps increasing and the consequence is that the size (i.e., number of switching ports) and cost of conventional Optical Cross-Connects (OXCs) are excessively enhanced. Therefore, the technique called Waveband Switching (WBS) has been proposed to reduce the number of switching ports for saving the costs. At the same time, the survivability for optical networks is a very important issue since each wavelength channel has the transmission rate over several gigabits per second and the failures may lead to a lot of traffic blocked. Combining the WBS technique and survivability in optical networks, in this paper we comprehensively review the existing survivable schemes in WBS optical networks which are quite different from conventional survivable schemes in Wavelength-Routed (WR) optical networks. Then, we analyze the shortages of the current researches and prospect the challenges for survivability in WBS optical networks. Finally, we propose new ideas for designing survivable schemes to well guide the future work of researchers in WBS optical networks.