Patent ID: 8270300

Claim:
A method for checking support of a function at network nodes of an Automatically Switched Optical Network, the network including: a transport plane comprising at least a source network node, a destination network node and at least one intermediate network node arranged for the transport of user signals through the network; and a control plane comprising at least a source control plane element, a destination control plane element and at least one intermediate control plane element interconnected through messages of a signaling protocol, for controlling the source network node, the destination network node and the at least one intermediate network node respectively for configuring a connection from the source network node to the destination network node crossing the at least one intermediate network node; the method comprising, in case the connection is not configured, the steps of: transmitting a first message from the source control plane element to the destination control plane element crossing the at least one intermediate control plane element to indicate a request of the configuration of the connection, that includes a request of the check of support of an operation, administration, and management function of the connection by all network nodes of the connection, said first message including a first field which is unchanged if the operation, administration, and management function is supported between the source network node and the at least one intermediate network node, including the at least one intermediate network node, but the first field indicates that the operation, administration, and management function is not supported if said function is not supported between the source network node and the at least one intermediate network node, including the at least one Intermediate network node, wherein the connection is a Multi-Protocol Label Switching (MPLS) Label Switched Path (LSP) connection; transmitting the first message from the at least one intermediate control plane element to the destination control plane element when the first field is unchanged, indicating that the function is supported and when the first field indicates that the operation, administration, and management function is not supported; and receiving at the source control plane element a second message transmitted from the destination control plane element that indicates an answer to the request, the second message including the first field that indicates whether or not the operation, administration, and management function is supported by all the network nodes of the connection.