Efficient Partial Recovery of Flexible-Rate Transceivers with SDN-based Asymmetric Multipath Routing of IP Traffic

New optical elasticity features of bandwidth-variable transponders together with intelligent recovery capabilities in optical transport networks might enable partial recovery of an optical wavelength capacity. However, current ECMP-based mechanisms are unable to utilize partially recovered links efficiently. This paper presents software defined network (SDN)-based asymmetric multipath routing, enabling the usage of these links. By introducing adapted fine-granular load balancing and segment routing mechanisms, this new concept aims at making the most of the partially recovered capacity and thus reducing the required standby capacity for restoration. We outline the investigated SDN control architecture and introduce the practical design and implementation approach.