—Since the energy crisis and environmental protection are gaining increasing concerns in recent years, new research topics to devise technological solutions for energy conservation are being investigated in many scientific disciplines. Specifically, due to the rapid growth of energy consumption in ICT (Information and Communication Technologies), lot of… (More)
—Since the Internet consumes a large (and increasing) amount of energy, " green " strategies are desirable to help service providers (SP) operate their networks and provision services more energy efficiently. We focus on green provisioning strategies for optical wavelength-division multiplexing networks. A number of approaches from component layer to… (More)
This article studies how next-generation optical access networks can exploit the properties of wireless connectivity to provide improved quality of service to users, and reports on a corresponding experimental prototype as well. Optical access networks using the passive optical network architecture are being increasingly deployed worldwide for… (More)
This paper gives an overview of software-defined optical networks (SDONs). It explains the general concepts on software-defined networks (SDNs), their relationship with network function virtualization, and also about OpenFlow, which is a pioneer protocol for SDNs. It then explains the benefits and challenges of extending SDNs to multilayer optical networks,… (More)
The hybrid wireless-optical broadband access network is emerging as a promising technology to provide economical and scalable broadband Internet access. In this cross-domain network architecture, end users receive broadband services through a wireless, mesh front end that is connected to the optical backhaul through gateway nodes. In this article, we… (More)
The energy crisis and environmental protection are gaining increasing concern in recent years. ICT (Information and Communication Technology) has a significant impact on the total electricity consumption all over the world. Telecom networks, being an important part of ICT, consume significant energy since more network equipment is deployed annually.… (More)
Energy consumption of content-delivery networks employing optical infrastructure is improved if some backbone nodes can also host content. In a typical scenario, up to 18% energy is saved using this approach vs. monolithic datacenter architecture.