Japan is well-known as the country where the penetration ratio of the intelligent cellular phone system is large. In 2007, it was reported that in the cellular phone system in Japan, the total volume of data traffic became larger than that of voice traffic. Now, the telecommunication infrastructure is going to be converged with broadcasting infrastructure. 2011 is called as the first year of the full digital age. Towards 2011, the following technical challenges may arise: development and deployment of end-to-end architecture on the existing complex IPv4-based Internet; development of Japanese infrastructure, which is globally competitive and globally interoperable; development of new applications and new business models in the ubiquitous networking environment; development of Internet systems as a social infrastructure; integration with the real-space (i.e. integration of physical space and cyber space); NGN (Next Generation Network) and FMC (Fixed Mobile Convergence); and development and deployment of the unwired Internet environment. In order to progress the actions listed above, we must establish strong collaboration among industry and academia. This volume looks into the challenges and opportunities.