Abstract — With

high-bandwidth and on-demand applications continuing to emerge, next-generation core optical networks will require significant improvements in capacity, configurability, and resiliency. These advancements need to be achieved with ar-chitectures and technologies that are scalable with respect to net-work cost, size, and power requirements. To investigate the limi-tations of extending today’s solutions to meet these goals, a North American backbone network with a ten-fold growth in traffic is modeled. The results of this study illuminate at least three areas that will potentially require innovative solutions: transmission modulation formats, switching granularity, and edge traffic grooming. In addition to probing issues related to increased capacity, configurability is also examined, mainly in the context of switching architectures. Advanced network protection is dis-cussed as well, at a high level. A central theme is how to harness the trend of optics scaling better than electronics. Throughout the paper, potential advancements in architecture and technology are enumerated, to serve as a foundation for the research needed to attain the goals of next-generation core networks. Index Terms — All-optical regeneration, all-optical switch, backbone networks, configurability, core networks, grooming