AS9354 TDNC Community Network Center Inc.

AS9354 (TDNC) is held by Community Network Center Inc. (CNCI), a Nagoya-based cable holding company that is one of Japan's largest multiple-system operators. It was formed as an alliance of cable television companies in the Tokai region and today sits above a group of local cable operators, whose subscribers this AS carries.

What it's used for

This is a cable eyeball network operated at group scale. RIS observes 37 IPv4 prefixes carrying about 200,448 addresses, a single IPv6 /32 (2405:7000::/32), and 100 BGP neighbours. Two hundred thousand addresses in only 37 aggregates — a run of /18s out of 221.118.0.0, plus /19s and /20s — is subscriber pooling, not customer-block deaggregation. The hundred neighbours is higher than a single regional ISP would show, and that fits a holding company aggregating several cable operators' traffic and interconnecting on their behalf at Japanese exchanges; it is still nowhere near a wholesale transit fabric given the address volume. The reverse DNS settles the role: sampled addresses resolve to global221-64-005.aitai.ne.jp and similar across the aitai.ne.jp zone (the group's Aitai net consumer ISP brand), and to 222-229-96-5.catv.medias.ne.jp and catv-219-099-000-005.medias.ne.jp — literally catv in the hostname — for the Media's Network operator. Uniform per-subscriber naming across multiple member-company brands is the signature of a consumer cable ISP group.

Notable

• CNCI is a holding company: the AS carries several member cable operators' subscribers under their own rDNS brands rather than one unified name.
• The catv. PTR labels are an unusually explicit confirmation of cable access.
• IPv6 is present as one /32 but is not deaggregated.

Interesting

The AS handle TDNC preserves the company's original name, Tokai Digital Network Center, from before it was renamed Community Network Center — a fossil in the registry that outlived the branding.