Novel models for efficient shared-path protection

Summary form only given. As widespread deployment of high-capacity dense wavelength-division multiplexing (DWDM) systems is envisioned, achieving efficient shared-path protection, which protects a bandwidth guaranteed connection from a single link (node) failure using a link (node) disjoint pair of active path (AP) and backup path (BP), becomes a key design consideration. We have introduced two parameters (ε and μ) into the objective function of integer linear programming (ILP) models for dynamic provisioning of restorable, bandwidth guaranteed connections using shared-path protection. By using ε (0 < ε < 1), we can obtain a lower total bandwidth (TBW) consumption than using ε = 1 as in the existing models. In addition, using 1 ≥ μ > 0 can avoid the pitfall of choosing very long backup paths that is common in existing models (where μ = 0), thus reducing the BP length and consequently restoration time. One of the pleasantly surprising results is that, by combining an appropriate ε (e.g., 0.1) and μ (e.g., 0.2), the proposed models can achieve a TBW consumption with shorter BP than the existing ones.