To meet diverse, bandwidth-intensive applications envisioned in future optical networks, as well as address the shortcomings of the current Internet, novel networking technologies will be of great importance. We discuss several key issues for the future Internet, including network virtualization mechanisms, a programmable network architecture, parallelism of optical transmission, and guaranteed quality of service provisioning. Moreover, a new type of virtualized optical substrate architecture is proposed that utilizes optical orthogonal frequency division multiple access (OFDMA), along with subwavelength switching and generic packet routing to realize the network bandwidth programmability. The main features, benefits, and design and implementation challenges of optical OFDMA networking based on sliceable routers are also described. Finally, an adaptive subcarrier allocation and assignment algorithm for future OFDMA-based networking is investigated, and a performance comparison between the proposed approach and legacy time division multiple access (TDMA)-based techniques is drawn.