Distributed lightpath establishment techniques using Multi-wavelength Reservation Protocols in WDM optical networks

Abstract

Distributed lightpath establishment in WDM optical networks involves, apart from routing, two important steps, namely wavelength selection and wavelength reservation. In uni-wavelength reservation protocols, often multiple connection requests unknowingly compete for the same wavelength, even when other free wavelengths are available, resulting in a collision. Attempting multiple wavelengths for reservation in that case improves the probability of successful reservation as exhibited in Destination Initiated Multi-Wavelength Reservation Protocol (DIMRP). So we extend the concept of multi-wavelength reservation to Split Reservation Protocol (SRP) next and then to Markov-based Split Reservation Protocol (MSRP) and find that performance is improved considerably for them too. Initially, we discuss three multi-wavelength schemes separately and compare performance of these protocols with related uni-wavelength protocols in their own category. Then we undertake a comparative study among the three proposed multi-wavelength protocols to find that multi-wavelength MSRP performs the best.