Availability-Constrained Shared Backup Path Protection (SBPP) for GMPLS-Based Spare Capacity Reprovisioning

Shared-backup path protection (SBPP) has been widely studied in the GMPLS networks due to its efficient spare capacity sharing and flexibility in service provisioning. This paper presents a model for evaluating the end-to-end (E2E) availability of an SBPP connection by assuming that no more than two simultaneous failures could possibly occur in the network. To minimize the redundancy while meeting the E2E availability requirement, a framework of partial restoration from any unexpected failure is created. Based on the proposed availability model, a novel Linear Program (LP) formulation is introduced, which aims to perform the spare capacity allocation for SBPP connections. A new availability-aware spare capacity reprovisioning (SCR) architecture is then introduced for dynamic provisioning of SBPP connections. Extensive simulations are conducted to validate the proposed availability model and demonstrate the effectiveness of the SCR architecture.