in a telecommunications network , such as an optical mesh network , satisfying a demand from a start node to an end node , the network is automatically provisioned from a service path to a restoration path after a failure occurs in the service path . each affected node in the network eventually receives an indication of the occurrence of the failure in the service path . if the node is an intermediate node of the service path , then the node transmits a failure message to its next node along the service path . if the node is the end node of the service path , then the node transmits a restore message to its previous node along the restoration path . if the node is an intermediate node of the restoration path , then the node transmits a restore message to its previous node along the restoration path . in addition , the node reconfigures its cross - connect for the transition from the service path to the restoration path .