Patent ID: 6904438

Claim:
A method for counting channels at a node of a multi-channel optical network, the node being connected to a following node and a preceding node by an optical communication line capable of carrying a plurality of information optical channels, the method comprising exchanging of information structures between the nodes, wherein each of the information structures specifying particular optical information channels in use at a network section; the method comprising steps of providing at the node: an information structure DRP indicating specific information optical channels to be dropped at said node, and an information structure ADD indicating specific information optical channels to be added at said node, obtaining an information structure RCV indicating specific information optical channels received from the preceding node, and forming an information structure FWD by using the information structures RCV, DRP and ADD, the FWD indicating specific information optical channels to be forwarded from said node to the following node, and thereby informative of the number of said channels (NOC), providing the following node with the information structure FWD serving as an RCV of the following node.