Optimal routing strategy for multi-constraint scenarios in software-defined optical transport networks

To address the challenge of computing the optimal loop-free path under multiple complex logical constraints in a software-defined optical transport network with hybrid optical-electrical layer scenarios, this paper proposes an optimal path calculation method for complex logic combination constraints. First, a unified constraint expression is employed to describe the constraints, simplifying and decomposing the logical relationships. The network topology is then transformed accordingly, mapping various complex constraints onto the original structure. Next, an improved K-shortest path algorithm is applied to obtain, in a single computation, the path that satisfies multiple complex constraints, including 'AND', 'OR' and bidirectional link requirements, while ensuring the global optimal solution. Experimental results demonstrate that this method offers higher practical value compared to other algorithms.