With the exponential leap in the amount of data being handled across society today, servers, routers and other network equipment may soon be unable to crunch data at sufficient speed, and there are also concerns about the increasing amounts of power consumed by such equipment. Current network devices convert optical data transmitted through optical fibers into electronic data for processing, and this both increases power consumption, and acts as a brake on processing speeds. This is why researchers throughout the world are conducting R&D on enabling network devices to process data optically.

The biggest hurdles to enabling optical processing are the creation and integration of small enough optical memories, and minimizing the amount of power they consume. Using photonic crystals^*1, NTT Basic Research Laboratories and NTT Photonics Laboratories have developed an optical memory cell with power consumption over 300 times lower than previous records, and have also succeeded in integrating optical memory cells to create the world's first optical random-access memory (RAM) chip. By enabling optical data to be held and utilized as it is without converting it to electronic data, this achievement paves the way for creating much speedier network equipment that also consumes much less power.

NTT researchers continue to work on wafer-scale integration of optical RAM chips and their application to network equipment.

With the rapid evolution and spread of network technologies in recent years, all sorts of devices — consumer appliances, audiovisual systems, housing equipment, sensors, etc. — in addition to PCs and other ICT devices have come to be connected to networks. In the past, lack of compatibility between the different connectivity specifications used meant that new network environments were required every time for the devices connected. To resolve this situation, the OSGi Alliance^*1 created open specifications that enable interconnectivity and interoperability between network-enabled devices. In June 2012, the OSGi Alliance released its Residential specification for home networks.

NTT Service Evolution Laboratories is leveraging the experience it gained from leading the standardization processes to create the Residential specification to conduct research aimed at developing a general-purpose Home ICT platform that enables all sorts of devices in the household to interconnect and cooperate through a network.

The Home ICT platform is being eyed as technology for simplifying home and office network environments and saving both space and energy through the use of devices called home gateways for the unified distribution of services (software) required to use devices connected to the home network.

Home ICT Platform System STEP 1.5 released in fiscal 2011 was already equipped with the basic functions for distributing services to home gateways. These basic functions were refined, and a malfunction management feature for improving home gateway maintenance was added to the next version, Home ICT Platform System STEP 2.0, that was released in fiscal 2012.

Home ICT Platform System STEP 1.5 became commercially available in August 2011 as the FLET'S JOINT service offered by NTT East and NTT West.

As awareness of environmental issues grows, telecommunications carriers are under increasing pressure to reduce the electricity consumption of their optical networks.

The electricity consumed by the optical network units (ONUs) installed in customer homes is particularly critical, since their sheer number means that they account for a very large chunk — according to one estimate, over 50% — of the electricity consumed by a whole network. It is for this reason that NTT is focusing on reducing the amount of electricity consumed by ONUs through integration on single chips and reducing the number of parts they contain. In addition to such hardware design measures, the adaptive power saving control technology being developed by NTT Access Network Service Systems Laboratories is also attracting attention as a methodology-based solution.

This technology regulates the amount of electricity consumed according to the amount of traffic between the ONUs in each home and optical line terminals (OLTs) on the exchange side. For example, when a customer is not using the service, these devices now slip into a sleep mode, reducing electricity consumption to the bare minimum. The technology also adjusts transmission speeds between OLTs and ONUs according to usage status so as to save electricity.