Operating a network close to the “zero margin” regime thanks to elastic devices

Despite of recent progress in research on the subject of modernisation and automation of networks, most legacy optical networks still operate statically: when a connection has been set-up it is rarely reconfigured. Exception occurs in a case of a node/link failure: in that case reconfigurations concern only the traffic with a specific class of service (CoS) where a given resiliency has to be ensured. When network reconfigurations are needed, the newly set up connection has to be promptly operational, independently of the actual network state.