Survivability concepts for all-optical transport networks

In the future the existing transport network will be enhanced by adding a new network layer based on optical frequency division multiplexing. This network is characterized by an efficient cross-connecting of very high bit rate streams (10 Gbit/s or higher) carried by an optical frequency channel. In case of a cable break or node failure a huge amount of data will be lost. The high traffic concentration in all-optical transport networks makes network restoration of paramount importance. A scheme for restoration methods is presented. Four methods are assessed qualitatively and quantitatively using a ten node sample network. The results indicate that the cost for the redundancy to be installed may be high in all cases.