p-Cycle Protection without Wavelength Converters in Wavelength Division Multiplexing

The wavelength division multiplexed (WDM) networks having single fiber structure, can be protected using pre-configured protection cycles (p-cycles) established with spare wavelengths. p-Cycles can provide protection to the individual wavelength carrying working traffic. In this scheme it is essential for all nodes to have 100% wavelength conversion capability. It will be interesting to investigate protection with p-cycles without wavelength converters. It is observed that the Hamiltonian network can be protected by a single Hamiltonian p-cycle by using a separate fiber for protection. Thus on failure, switching can be done to protect the whole fiber link without considering individual wavelength. A single fiber based protection is therefore sufficient in providing protection to the WDM network without wavelength converters, as only fiber switching will be done. With this approach, we compensate the wavelength converters by additional fiber thus reducing converters cost significantly.