AS131971 JPNIC-4Byte-ASBLOCK-AP

AS131971-67 - JPNIC-4Byte-ASBLOCK-AP · registered in Japan

IPv4 addresses2,0481 prefixes · <0.001% of announced IPv4

Rank in Japan#454largest network in JP by IPv4 space, of 724 · <0.01% of JP

Rank worldwide#21,781of 79,396 networks with IPv4

IPv61 x /32 (65,536 x /48)1 prefixes

CountryJapan745 ASNs registered there

Open AS131971 in ASN lookup Look up an IP in this network (202.1.208.1) All networks in Japan

IPv4 prefixes

All 1 prefix, in address order.

202.1.208.0/21

IPv6 prefixes

All 1 prefix.

2407:9900::/32

Other ASNs named JPNIC-4Byte-ASBLOCK-AP

1 other network uses the same organisation name; together with AS131971 they announce 2,304 IPv4 addresses.

ASNNameIPv4 addresses

AS131913AS131913-9 - JPNIC-4Byte-ASBLOCK-AP JP256

Similar-sized networks in Japan

ASNNameIPv4 addresses

AS59105#451 HOMENOC - Home NOC Operators Group2,048

AS63771#452 BGPNAP - Border Gateway Protocol Network Analysis Project2,048

AS63774#453 KAMOIKE-NET - Kamoike.net LLP2,048

AS131986#455 BB4U-NET - ITOCHU Cable Systems Corp.2,048

AS131987#456 MCDR-NRT - MC Digital Realty, Inc.2,048

AS146976#457 KNET - Kvision Co.,Ltd.2,048

IP-to-ASN data: iptoasn.com (public domain). Snapshot downloaded 2026-11-11, refreshed daily. Ranges are what each network announces in BGP, not registry allocations. Data sources