Long-Reach Passive Optical Network (LR-PON) is widely acknowledged as a promising solution for communication system in smart grid. Survivability is one of the key issues in the planning of LR-PON because massive high-rate traffic flows may be interrupted in case of network component failure. However, the survivability issue of LR-PON is addressed in few works. Most of previous works focus on single distribution fiber failure and remain untouched the simultaneous failure of multiple distribution fibers. In this paper, we focus on the survivability of LR-PON against single Shared-Risk Link Group (SRLG) failure. A reliability model is proposed to represent the probability of reliable connection for each Optical Network Unit (ONU). Based on this reliability model, we propose a novel Backup Fibers Protection (BFP) approach, aiming at the optimization of joint allocating backup capacity and deploying backup fibers. Through extensive simulation, we investigate the performance of BFP and demonstrate its effectiveness in different scenarios.
