AS7686 ATNETHOME JCOM Co., Ltd.

ATNETHOME is held by JCOM Co., Ltd. (J:COM), Japan's largest cable-television operator. The handle preserves @NetHome, the cable-broadband ISP brand that J:COM's predecessor group ran before absorbing it.

What it's used for

• Two prefixes, 61.211.144.0/20 and 210.228.0.0/20 — about 8,200 addresses. No IPv6 is announced on this AS.
• Reverse DNS is straightforward cable-subscriber addressing: allNNNNNNNNN.allnet.ne.jp, sequentially numbered per address. allnet.ne.jp was the ISP domain of Titus Communications, a cable operator later folded into the Jupiter Telecom group that became J:COM.
• This is a legacy pocket of J:COM's subscriber space rather than the company's main network. J:COM's bulk cable-broadband customers are numbered on other, much larger ASNs.

Notable

• Residential space, and it should geolocate to Japanese households, not to a corporate address.
• JPNIC records the 61.211.144.0/20 allocation to 2001, under the ATNETHOME netname, and it still routes today — the brand is gone, the block is not.

Interesting

• @NetHome was launched in 1999 as a joint venture between Jupiter Telecom, Sumitomo Corporation and the American @Home Network, whose cable-modem model it imported. @Home Network went bankrupt in 2001; the Japanese venture survived, was later rebranded ZAQ, and was eventually merged away entirely — leaving this AS handle as one of the few places its name still appears.