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AS17977NF Park Bldg.3F, 9-15, Futaba 2-Chome

JapanRegistryAPNIC

As of 10th November 2026, AS17977 (NF Park Bldg.3F, 9-15, Futaba 2-Chome), a network registered in Japan with APNIC, originates 2 IPv4 prefixes covering 8.2k addresses. By IPv4 address space that makes it the 12,069th-largest of the 80,723 networks we see originating IPv4, and the 342nd-largest of 737 in Japan. It is seen behind 1 upstream network, most often AS7473 (Singapore Telecommunications Ltd). Every one of its announcements has a valid RPKI ROA, and none are RPKI-invalid. 100% of its routes reach at least 90% of full-feed peers.

At a glance

IPv4 prefixes

2

IPv6 prefixes

0

IPv4 addresses

8.2k

IPv6 /64s

0

Upstream graph

The networks AS17977 is seen behind, one and two hops out, drawn from real AS paths.

AS17977Toward the internet core
Upstream graph for AS17977: 3 neighbouring networks observed beyond it across 2 levels. The same networks are listed in the tables below.AS17977NF Park Bldg.3F, …This networkAS7473Singapore Telecom…AS6461Zayo BandwidthAS6939Hurricane Electri…

Networks observed one and two hops upstream of AS17977 in real AS paths. A thicker line means more vantage points saw that adjacency, so weight tracks how well attested it is — not how much traffic it carries. Adjacency is an observation; whether it is a transit purchase or a settlement-free peering is an inference, and is labelled as one wherever we show it.

Neighbouring networks

2

adjacent networks

Upstreams
150%
Peers
150%
Downstreams
00%

Networks carrying this one's traffic toward the rest of the internet.

Upstreams of AS17977
NetworkCountryRelationshipPathsVantage pts
AS7473Singapore Telecommunications LtdSGPeer15276

Prefixes

The largest blocks AS17977 originates, widest first.

Largest prefixes originated by AS17977
PrefixAddressesVisibility
120.72.64.0/204.1k76/76
203.173.64.0/204.1k76/76

Routing health

How AS17977's own announcements validate against RPKI and how far they propagate. The same measures for the whole routing table are on the routing table in numbers.

RPKI origin validation

  • Valid100.0%2
  • Invalid0.0%0
  • No ROA0.0%0

Propagation

  • Globally propagated90% of full-feed peers or more100.0%2
  • Partially propagated40% to 90%0.0%0
  • Seen by few peersUnder 40%0.0%0

Prefix sizes

IPv4 — 2 prefixes

Recent changes

Announcements that started or stopped since 11th Oct 2026.

No announcement by AS17977 started or stopped in this period.

Routing data derived from RouteViews MRT archives, BGPKIT relationship inference and public registry data.