AS9617 ZAQ JCOM Co., Ltd.

AS9617 (ZAQ) is held by JCOM Co., Ltd., Japan's largest cable television and broadband operator. ZAQ is J:COM's consumer internet brand: the cable-ISP side of the company that sells J:COM NET alongside its TV, telephony and mobile bundles.

What it's used for

This is one of the larger eyeball networks in the range and the routing evidence is unambiguous. It announces 85 IPv4 prefixes covering 1,163,264 addresses, including four /15s (119.24.0.0/15, 49.250.0.0/15, 180.220.0.0/15, 122.196.0.0/15) and a long series of /16s and /17s, plus 33 IPv6 prefixes, mostly /37s carved from 2400:3800::. Every sampled address resolves under rev.zaq.ne.jp with hex-encoded per-address hostnames like zaq77180005 and zaqb4dc0005. That is machine-generated naming for an enormous pool of subscriber modems, generated from the address itself because no human is going to name a million cable customers.

The single observed BGP neighbour is the point that settles the role. Over a million addresses behind one upstream adjacency is a pure access network: it consumes transit rather than selling it, and it does not peer widely. All of that traffic is J:COM's own residential subscribers.

Notable

• The IPv6 plan is deliberately fine-grained, carving 2400:3800:: into many /37s rather than announcing one aggregate. That is regional or headend-level segmentation of a national cable footprint.
• J:COM's regional cable operations sit on separate ASNs. Its Oita network, for example, is [AS9614](https://asn.ipinfo.app/AS9614). AS9617 is the ZAQ consumer platform.