Home Prefix Lookup81.203.0.0/16

81.203.0.0/16 - IIJ Internet Initiative Japan (AS2497)

IPv4APNICallocatedAS2497IIJ Internet Initiative Japan Inc. RPKI Valid

CIDR

81.203.0.0/16

IP Version

IPv4

Addresses

65.5K

Mask

/16 (255.255.0.0)

Country

🇯🇵 Japan

City

Chiyoda City

RIR

APNIC

Status

allocated

Allocated

2002-11-12

Announced BGP Routes

1 of 1 route

RPKI:

IRR:

Swipe sideways to see all columns →

Prefix	Origin AS	RPKI	IRR	Last Seen
81.203.0.0/16	AS2497 IIJ Internet Initiative Japan Inc.	Valid	Other IRR	2026-10-11

RPKI ROAs

Prefix	Origin	Max Length	Trust Anchor
81.203.0.0/16	AS2497	/16	apnic

IRR Route Objects

Origin	Registry	Maintainer	Modified
AS2497	Other IRR	MAINT-AS2497	2026-09-15

Transfer History

Registry transfers of 81.203.0.0/16, blocks inside it, or blocks containing it.

81.203.0.0/16inter-RIRTransfer · 2025-12-22
VODAFONE ONO, S.A.
🇪🇸 ES RIPE NCC
→
Japan Network Information Center/iij
🇯🇵 JP APNIC

Date	Resource	From	To	Type
2025-12-22	81.203.0.0/16inter-RIR	VODAFONE ONO, S.A. 🇪🇸 ES RIPE NCC	Japan Network Information Center/iij 🇯🇵 JP APNIC	Transfer

Origin ASN

AS2497

IIJ Internet Initiative Japan Inc.

Related Prefixes

More prefixes of AS2497

All prefixes of AS2497 →

Geolocation

Country🇯🇵JapanJP

RegionTokyo

CityChiyoda City

Coordinates35.6916, 139.7680 ↗

Learn more

RPKI and ROAs explainedWhat RPKI valid, invalid and no ROA mean
RPKI validatorCheck ROA coverage for any prefix or ASN
What is BGP?How prefixes are announced and routed
More-specific prefixesGlossary: covering and more-specific routes
IPv4 transfers in the APNIC regionWho bought and sold address space recently

API

Open

GEThttps://api.ipctl.io/v1/prefix/81.203.0.0/16

Returns prefix allocation, BGP routes, and more-specific subnets.

curl -s "https://api.ipctl.io/v1/prefix/81.203.0.0/16" | jq

External Links

RIPEstat