Joint working and spare capacity design of node-inclusive span-restorable optical networks

We develop a joint working and spare capacity network design model for node-inclusive span restoration, a recently introduced mesh survivability mechanism that provides node-failure restorability and capacity efficiency close to that of path restoration, with an operational simplicity close to that of span restoration. In addition to significantly reduced capacity requirements, networks designed with the new model to be span-failure restorable only are, in fact, nearly fully node-failure restorable with no additional spare capacity needed. A variant of the ILP design model is also shown to explicitly assure node-failure restorability with little to no extra capacity beyond that needed for span-failure restoration.