[Jun, 2006] Tokai Digital Network, Inc. (TDNC)

Currently forming cable alliances in the Tokai Region, Tokai Digital Network, Inc. (TDNC hereafter) is a leader in the next-generation movement in the world of CATV toward full integration of broadcasting and communications. TDNC recently constructed a 10-Gbps, high fault-tolerance ring network incorporating Hitachi Cable products, including the eWAVE next-generation transmission system, AlaxalA router, and Apresia L2 switch. The result is an integrated backbone with expandability up to 40 Gbps. To find out more about the backdrop and process of this integration, we spoke to Mr. Tadashi Morimoto (Executive Director), Mr. Katsuhisa Sasagawa (Acting General Manager of Engineering Development Department), Mr. Shinji Yano (Group Manager of Communications Service Group in Engineering Development Department), and Mr. Atsushi Hibino (Subsection Chief of System Department of Himawari Network Co., Ltd.).

TDNC operates and manages infrastructure combining 18 CATV companies in the four prefectures (Aichi, Gifu, Shizuoka, and Mie) in the Tokai Region, where broadband penetration now exceeds 50%. With the three major CATV companies - Himawari Network, Katch Network, and Chita Medias Network - TDNC constructed a 10-Gbps network for the upper connection and undertook large-scale backbone integration with a unified Autonomous System (AS) *1 .

"As of last fall, the number of households connected to our network was 950,000,"

says Mr. Morimoto, discussing background factors and reasons for this integration.

"The number of households using the Internet now exceeds 300,000. Bandwidth usage grows 30 to 40% every year, which is even higher than the growth in numbers of subscribers. The average for the three companies is 2.7 Gbps, reaching 4 Gbps during peak hours. With future services in mind - including the launch of VOD (video on demand) and the accelerating fusion of broadcasting and communications - we began considering expanding network capacity to 40 Gbps. Integrating the backbone also enables efficient use of bandwidth by combining the upper lines of the Internet. The reason for integrating is to reduce operational burdens, suppress costs, and improve service quality. We hope to establish a strong platform as part of a loose collaboration that respects the individual character of each station."

Preparations for backbone integration took approximately one and a half years. Mr. Hibino of Himawari Network discussed this process.

"We lacked objective data for assessing the advantages and disadvantages of backbone integration, so we decided the people in charge at each station should meet for a discussion. We formed a study committee around January 2005, and started out by considering products from virtually every vendor."

Mr. Yano, assigned responsibility for building the network, describes the vendor selection process.

"We screened the products based on our specifications. The decisive factor was the vendor's track record. We knew about Apresia because we'd tested it before. We made the final decision also keeping in mind the fact that Hitachi Cable had constructed the TDNC network four years previously."

The new network built by TDNC is a 10-Gbps ring network based on the Apresia8004 L2 switch, which is supported by Hitachi Cable. It incorporates AlaxalA7702R routers and is configured to connect integration stations and higher-level carriers.

Mr. Yano gave the reasons for adopting MMRP, Hitachi Cable's original fast-switching function for Ethernet rings.

"We selected MMRP because it switches routes quickly. Slow switching generally leads to service suspensions when a failure occurs. MMRP met our conditions of use for fault tolerance. Before installing devices at each station site, we modeled a configuration and ran test operations for a month. As we expected, we encountered no problems with Apresia."

Mr. Hibino also gives Apresia high marks.

"It instills confidence in users. With many imported products, the development focus is unclear. Apresia is made tough, and the clear product concept is that it's meant to resist breakage. Network devices are used in various environments, and I'm sure it's difficult for vendors to test their equipment under all imaginable conditions. But Apresia is built so that it can handle seemingly any and all possible system extensions. I was surprised, honestly. Though if I could register one quibble, it would be nice to have a wider color selection."

Mr. Hino also has high expectations for Hitachi Cable.

"There was a time when I didn't know much about Hitachi Cable's network equipment operations. I had my doubts a cable manufacturer could provide decent equipment,"

he says with a laugh.

"We found that Hitachi Cable responded far faster than other vendors. If we asked them to verify certain settings by the end of the week, they'd do so without fail. I now consider Hitachi Cable to be a manufacturer we can do business with. Just one look at the mounted rack supports this view - Hitachi Cable's rack is tidy. All of its parts give the impression of neatness.
Traffic continues to grow, and further development, money, and time will be needed to go beyond the 40 Gbps barrier. Still, I hope Hitachi Cable will continue do its best, perhaps even setting global standards as a manufacturer representing Japan."

The ever-increasing pool of cable Internet subscribers and traffic in the Tokai Region are the result of a strategy emphasizing digitization and cost effectiveness, carrying on a concept established with Tokai Digital Network, Inc. itself. The recent decision to embark on further network construction addresses concerns about next-generation networks and improvements in services for CATV companies. To implement network construction requirements, we proposed equipment based on aspects such as reliability, extensibility, and interoperability. We provided consistent support for construction, from the pre-verification stage to device installation to post-deployment maintenance. We plan to continue striving to serve our clients as a reliable vendor and a key figure in the coming age of full-scale high-capacity networks and a high-energy Tokai Region.