109 each node 101 102 109 is typically at a different geographic location however as those skilled in the art will appreciate nodes may be collocated in the same geographic location and at the same or different physical locations however in the illustrative embodiment of the invention mesh network 100 represents a portion of a national network for the united states considering a typical situation each node might represent a different switching or routing office or a different city node 101 may for example be located in san francisco calif node 102 may be located in phoenix ariz node 108 may be located in new york n y and node 109 may be located in atlanta ga in the optical communications system utilizing the mesh network 100 communications occurs over multiple optical wavelengths that are multiplexed fiber optic links 121 122 123 135 link the various nodes 101 102 109 to form mesh network 100 each link may include multiple optical fibers multiplexing of optical wavelengths is known and various arrangements are available in the prior art to provide multiplexed optical wavelength communications in the example shown in fig1 only four multiplexed wavelengths u03bb 1 u03bb 2 u03bb 3 u03bb 4 are shown for purposes of clarity each wavelength is represented by arrows to indicate the routing of that wavelength component in mesh network 100 however the invention is applicable to network arrangements in which any numbers of optical wavelengths are multiplexed together the particular problem to which the present invention provides a solution is illustrated in.