Method of assigning carrier frequencies in an optical transmission network

A method of assigning optical carrier frequencies to signals to be transmitted in an optical transmission network using wavelength division multiplexing, said frequencies belonging to a comb of optical frequencies, the signals received after transmission in said network and carried by a given carrier frequency having a mean error rate that depends on said given carrier frequency, and one or more transmission constraint parameters being associated with any signal to be transmitted, which method consists in:

• associating N sets of optical frequencies of the comb with N respective ranges of consecutive error rate values, each of said sets comprising frequencies generating a mean error rate in the associated range,
• defining a measured signal transmission constraint level that is a function of said transmission constraint parameter(s) and may take N distinct values referred to as constraint values,
• associating said N constraint values in increasing order respectively with said N sets of frequencies in decreasing order of the error rate values of the associated N ranges,
• assigning any signal to be transmitted a constraint value obtained by applying said measurement, and
• assigning said signal to be transmitted a carrier frequency belonging to one of said sets of frequencies that is associated with a constraint value at least equal to the constraint value assigned to said signal to be transmitted.