Patent ID: 7376086

Claim:
In a multiple element network, a method for providing a constraint based routing system to accommodate non-transitive exceptions, the method comprising the steps of: a) receiving a connection request for an end to end connection; b) selecting routing information having a pair of adjacent links associated with the multiple elements of the network, each link of the pair of links having a shared network resource; c) comparing the shared network resource to a database of exception sets, the exception sets including at least one non-transitive exception predetermined from a plurality of network resources, a non-transitive exception being where both a first and a second resource are adequate when considered alone, but the combination of the first and second resources is inadequate; d) confirming whether the shared network resource of the selected pair of links is contained within the database; and e) designing a pathway over the network for the end to end connection using the results of the shared network resource comparison; wherein inclusion in the pathway is inhibited for the shared network resource matching the predetermined exclusion set contained in the database.