AS9824 — JTCL-JP-AS JCOM Co., Ltd.

Network type: residential

AS9824 announces 23 IPv4 prefixes covering 4,745,216 addresses and 2 IPv6 prefixes.

About this network

AS9824 (JTCL-JP-AS) is held by JCOM Co., Ltd. — J:COM, Japan's largest cable multiple-system operator, headquartered in Tokyo and a KDDI/Sumitomo joint venture. The handle preserves the company's former name, Jupiter Telecommunications. This is the eyeball network behind J:COM's cable broadband service.

What it's used for

RIS sees 231 IPv4 prefixes carrying 4,745,216 addresses, plus 62 IPv6 prefixes, announced through only 31 BGP neighbours. Nearly 4.75 million addresses against a peer count in the low tens is the unmistakable signature of a residential access network: it consumes transit and peering to reach the internet on behalf of its own subscribers, and sells no meaningful wholesale service. The inventory is consistent with that — several /13s (42.144.0.0/13, 110.128.0.0/13, 27.136.0.0/13) and a long series of /16s, JPNIC space allocated to a national operator, not a patchwork of acquired blocks. Sampled reverse DNS is uniform and decisive: every address returns a generated NN-NN-NN-NN.rev.home.ne.jp PTR, home.ne.jp being J:COM's own subscriber domain.

Notable

• J:COM serves cable footprints across Sapporo, Sendai, the Kanto region, Kansai and Fukuoka, and sells TV, telephony, mobile and even electricity alongside broadband — but this AS carries the internet side.
• IPv6 is broadly deployed: 62 prefixes, including 2001:ff0:: and 2405:120x:: ranges, so subscribers are dual-stacked at scale.
• The uniform machine-generated rDNS across the whole footprint is what lets geolocation and abuse tooling recognise J:COM subscriber addresses on sight.

This description is AI-generated, best-effort context — not authoritative, and provided without any guarantee of accuracy.

Announced prefixes

• 27.136.0.0/13
• 42.144.0.0/13
• 59.166.0.0/16
• 59.168.0.0/14
• 60.58.0.0/15
• 60.60.0.0/15
• 60.62.0.0/16
• 61.21.0.0/16
• 61.22.0.0/15
• 61.24.0.0/14
• 110.128.0.0/13
• 116.64.0.0/15
• 116.214.16.0/21
• 116.220.0.0/14
• 119.168.0.0/13
• 124.140.0.0/14
• 124.144.0.0/15
• 125.8.0.0/13
• 203.165.0.0/16
• 210.20.0.0/16
• 210.194.0.0/16
• 220.152.0.0/18
• 220.152.64.0/19
• 2001:ff0::/32
• 2405:1200::/29

Upstream networks

• AS2497 Internet Initiative Japan Inc.
• AS2516 KDDI CORPORATION
• AS6939 Hurricane Electric LLC
• AS1299 Arelion Sweden AB
• AS9002 RETN Limited

Downstream networks

• AS4721 JCOM Co., Ltd.
• AS9617 JCOM Co., Ltd.
• AS9378 JCOM Co., Ltd.
• AS9614 JCOM Marketing Co.,Ltd.
• AS18134 JCOM Co., Ltd.
• AS23788 JCOM Co., Ltd.
• AS18136 JCOM Co., Ltd.
• AS18283 Chupicom Inc.
• AS24276 JCOM Co., Ltd.
• AS23808 TOSHIMA CABLE NETWORK CO.,LTD
• AS45675 JCOM Co., Ltd.
• AS7524 ITEC HANKYU HANSHIN CO.,LTD.
• AS23790 JCOM Co., Ltd.
• AS23635 CRCCMedia Co.,ltd
• AS7686 JCOM Co., Ltd.
• AS45690 Nihon Central TV Co.,Inc.
• AS24290 Heart Network Co.,LTD
• AS24255 Koshinomiyako Network, Inc.
• AS17961 mitene internet co., ltd.
• AS17534 NSK Co.,Ltd.
• AS9351 ZTV CO.,LTD

Adjacent networks

• AS2497 Internet Initiative Japan Inc.
• AS2516 KDDI CORPORATION
• AS4721 JCOM Co., Ltd.
• AS9617 JCOM Co., Ltd.
• AS6939 Hurricane Electric LLC
• AS9378 JCOM Co., Ltd.
• AS9614 JCOM Marketing Co.,Ltd.
• AS18134 JCOM Co., Ltd.
• AS23788 JCOM Co., Ltd.
• AS1299 Arelion Sweden AB
• AS18136 JCOM Co., Ltd.
• AS18283 Chupicom Inc.
• AS9002 RETN Limited
• AS24276 JCOM Co., Ltd.
• AS23808 TOSHIMA CABLE NETWORK CO.,LTD
• AS45675 JCOM Co., Ltd.
• AS7524 ITEC HANKYU HANSHIN CO.,LTD.
• AS7686 JCOM Co., Ltd.
• AS23790 JCOM Co., Ltd.
• AS23635 CRCCMedia Co.,ltd
• AS24290 Heart Network Co.,LTD
• AS45690 Nihon Central TV Co.,Inc.
• AS17961 mitene internet co., ltd.
• AS24255 Koshinomiyako Network, Inc.
• AS17534 NSK Co.,Ltd.

Internet exchanges

• BroadBand Internet eXchange Tokyo — Tokyo, Japan
• JPIX Tokyo — Tokyo, Japan
• Equinix Internet Exchange Tokyo — Tokyo, Japan
• JPIX Osaka — Osaka, Japan
• Network Service Provider IXP (Distributed IX in Edo) — Tokyo, Japan