A method for determining a master ring for an optical communications
network having nodes arranged in a plurality of interconnected ring
structures. (A master ring is a ring structure which contains every node
in the network exactly once, and which also respects the node ordering of
every individual ring.) An efficient solution to the master ring problem
is provided by advantageously limiting the enumeration process based on
the consistency of the enumeration of individual rings with each other.
Illustratively, an intersection graph of the network is generated; one or
more of the rings is chosen and possible openings of each of these rings
are enumerated; and a limited number of possible openings of one or more
other (i.e., non-chosen) rings are enumerated such that the enumeration
of the possible openings of the other (i.e., non-chosen) rings are
consistent therewith.