Taki Cho

Situation – The Taki Cho municipality (Shimane prefecture) in Japan recognized an immediate need to upgrade its broadband infrastructure. They teamed with Izumo Cablevision to explore their options and then build the network. The municipality and Izumo also embarked upon this project because most of the region is in a “blind spot” to terrestrial digital broadcast television.

The municipal leadership felt strongly that IP voice and RF video service support were absolute system requirements and that very high speed data transmission capability would be essential to permit future service expansion. As a result, Izumo opted to deploy an FTTP network as opposed to a more conventional HFC system. In addition, FTTP is getting closer to HFC in terms of economics for Japan, but far exceeds it in performance and bandwidth to accommodate more services.

Prospects – Considering the situation and the customer’s requirements, Wave7 Optics’ partners in Japan, Yagi Antenna, were able to offer the Last Mile Link system in order to meet all the service and bandwidth requirements of the municipality. In addition, the LML provides all of these services over a ‘single fiber’ architecture, which dramatically reduces costs, compared to other FTTP systems.

Solution – After a review of competing proposals, Izumo opted to deploy the LML, making Taki-Cho the first single-fiber FTTP network providing the triple play of voice, RF video, and data services in Japan. Single-fiber systems such as Wave7 Optics’ “Last Mile Link” equipment are less expensive to deploy and maintain than dual-fiber systems, which load upstream and downstream traffic onto separate fibers.

Yagi, who were responsible for the deployment of the LML equipment (from central office to customer premises) and the rest of the FTTP infrastructure, including the multi-layer switches, SIP server and video headend equipment, took an advantage of know-how they achieved through their extensive experience with similar projects and completed the system as planned by Izumo. Izumo Cable provided fiber interconnects to the Taki Cho government backbone fiber network. From these interconnects, “Last Mile Core” OLTs (optical line terminals) are deployed in the field in a distributed architecture and then connected to “Last Mile Gateway” customer premises devices as part of the first phase deployment.

This network has many innovative features, but one in particular caught the eye of a leading industry trade magazine in Japan that noted:

“The most remarkable character of LML is that it uses the 1550 nm of optical wavelength for RF Video and 1310 nm for data for both upstream and downstream data. This difference of optical wavelength enables a system construction with little bad effect between optical signals, such as SRS interference.”

Current Situation – Completed in a fast seven months, the $6.2 M project covers a region of 44 sq. km and now connects more than 1,300 homes. This figure represents more than 90 percent of the municipality’s homes and all Taki-Cho residents will be connected soon. Current services include 35 television (three tiers of RF video service) and two FM radio channels, symmetrical high-speed Internet connections, an interactive community teletext system, and VoIP (Voice over Internet Protocol) telephony based on the latest version of SIP (Session Initiation Protocol) and its extensions, which means Izumo can offer the full complement of telephone features such as call forwarding, caller ID, and “follow me.” The Last Mile Link also supports MGCP and NCS (Media Gateway Control Protocol and Network-based Call Signaling). The network is also unique in that Izumo offers each subscriber to select an individualized package of services on an “a la carte” basis.

“The Taki Cho deployment is the first triple play FTTP deployment in Japan, and we are very excited to be participating in this with our partner Wave7 Optics,” said Hirofumi Higuchi, Executive Officer and General Manager of Ohmiya Works. “We are breaking new ground with an exciting technology that provides subscribers with a powerful mix of services and bandwidth capability.