Cost analysis of grooming ports for IP-over-WDM network protection

The network cost associated with the protection of IP-over-WDM networks is studied. In such networks, traffic grooming is an important issue since it is not possible to set up lightpaths between every pair of label switching routers. This, however, increases cost due to the introduction of optical transceivers and electronic switching. We evaluate the cost of protecting an IP-over-WDM network, using two cost functions, which capture the transceiver and electronic switching costs. The minimum cost problem is mathematically formulated for two protection schemes: IP LSP protection; WDM lightpath protection. The cost effectiveness of the two protection schemes is compared.