AS7521 MFEED INTERNET MULTIFEED CO.

MFEED — INTERNET MULTIFEED CO., founded in 1997 as a joint venture of NTT and

IIJ. It operates JPNAP, one of Japan's main internet exchanges, along with data

centre, IPv6 transition (transix) and public time services.

What it's used for

• Running the JPNAP exchange fabrics in Tokyo and Osaka, where Japanese ISPs and content networks peer.
• Multifeed's own service and management infrastructure: the rDNS on its space is operational, not customer-facing — firewalls, VPN concentrators and servers under mfeed.ad.jp.
• Serving ntp.jst.mfeed.ad.jp, the widely used public NTP service that distributes Japan Standard Time from NICT's clocks.

Notable

• Only ~4,900 IPv4 addresses, which badly understates it. Like any exchange operator, the traffic it handles crosses peering LANs that are not globally routed, so none of it shows up in this AS's prefix count.
• Infrastructure with no honest commercial "kind": it is not an eyeball ISP, a hosting provider or a transit seller. Compare [AS7527](https://asn.ipinfo.app/AS7527) (JPIX), Japan's other major exchange operator.

Interesting

• The public NTP service means a very large share of clocks in Japan, on consumer routers and servers alike, are ultimately steered by hosts in this small AS.