Organization
Nippon Telegraph and Telephone Corporation
CORE
Registered
Apr 05, 2002
24 years ago
IPv4 Prefixes
5
41,728 addresses
IPv6 Prefixes
0
BGP Neighbours
1
1 upstream/peer · 0 downstream
Registration
AS Number AS2511 AS Name CORE Country Japan (JP) Registry APNIC Allocated Apr 05, 2002 Last Updated Mar 17, 2023 Status
active
WHOIS Server whois.apnic.net AS Description CORE - Nippon Telegraph and Telephone Corporation, JP Remarks Nippon Telegraph and Telephone Corporation Abuse Email [email protected] Abuse Phone +81-3-5297-2311 IPv4 Prefixes
5 prefixes · 41,728 addresses Routing data as of 2026-10-07 16:00 UTC
| Prefix | Range | Addresses |
|---|---|---|
| 163.138.0.0/17 | 163.138.0.0 – 163.138.127.255 | 32,768 |
| 163.138.128.0/19 | 163.138.128.0 – 163.138.159.255 | 8,192 |
| 192.5.216.0/24 | 192.5.216.0 – 192.5.216.255 | 256 |
| 192.26.94.0/24 | 192.26.94.0 – 192.26.94.255 | 256 |
| 192.47.167.0/24 | 192.47.167.0 – 192.47.167.255 | 256 |
IPv6 Prefixes
This AS does not currently announce any IPv6 prefixes.
BGP Neighbours
1 unique neighbour · 1 upstream/peer · 0 downstream. A neighbour can be seen on more than one side. Rows are ordered by AS paths: the number of BGP paths seen by RIPE RIS that contain the adjacency. Sightings count each IPv4/IPv6 route with the adjacency once per RIS peer that sees it (routes × peers), so they show how widely it is seen, not how many distinct routes it carries. Networks seen to the left of this AS in BGP paths, toward the route collectors — typically its transit providers (upstreams) and peers. Upstream & peer side (1)
AS Name AS paths IPv4 sightings IPv6 sightings AS173 NTTECL-AS - Nippon Telegraph and Telephone Corporation 266 1,669 0
Raw RDAP Response
{
"rdapConformance": [
"nro_rdap_profile_0",
"nro_rdap_profile_asn_hierarchical_0",
"cidr0",
"rdap_level_0"
],
"notices": [
{
"title": "Source",
"description": [
"Objects returned came from source",
"JPNIC"
]
},
{
"title": "Terms and Conditions",
"description": [
"This is the APNIC WHOIS Database query service. The objects are in RDAP format.",
"This information has been partially mirrored by APNIC from JPNIC. To obtain more specific information, please use the JPNIC WHOIS Gateway at http://www.nic.ad.jp/en/db/whois/en-gateway.html or whois.nic.ad.jp for WHOIS client. (The WHOIS client defaults to Japanese output, use the /e switch for English output)"
],
"links": [
{
"value": "https://jpnic.rdap.apnic.net/autnum/2511",
"rel": "terms-of-service",
"href": "http://www.apnic.net/db/dbcopyright.html",
"type": "text/html"
}
]
},
{
"title": "Whois Inaccuracy Reporting",
"description": [
"If you see inaccuracies in the results, please visit: "
],
"links": [
{
"value": "https://jpnic.rdap.apnic.net/autnum/2511",
"rel": "inaccuracy-report",
"href": "https://www.apnic.net/manage-ip/using-whois/abuse-and-spamming/invalid-contact-form",
"type": "text/html"
}
]
}
],
"country": "JP",
"name": "CORE",
"status": [
"active"
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2023-03-17T20:58:06Z"
}
],
"links": [
{
"value": "https://jpnic.rdap.apnic.net/autnum/2511",
"rel": "self",
"href": "https://jpnic.rdap.apnic.net/autnum/2511",
"type": "application/rdap+json"
}
],
"remarks": [
{
"description": [
"Nippon Telegraph and Telephone Corporation"
],
"title": "description"
}
],
"entities": [
{
"roles": [
"technical",
"administrative"
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2022-01-05T03:04:02Z"
}
],
"links": [
{
"value": "https://jpnic.rdap.apnic.net/autnum/2511",
"rel": "self",
"href": "https://jpnic.rdap.apnic.net/entity/JNIC1-AP",
"type": "application/rdap+json"
}
],
"handle": "JNIC1-AP",
"objectClassName": "entity",
"vcardArray": [
"vcard",
[
[
"version",
{},
"text",
"4.0"
],
[
"fn",
{},
"text",
"Japan Network Information Center"
],
[
"kind",
{},
"text",
"group"
],
[
"adr",
{
"label": "Uchikanda OS Bldg 4F, 2-12-6 Uchi-Kanda\nChiyoda-ku, Tokyo 101-0047, Japan"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"tel",
{
"type": "voice"
},
"text",
"+81-3-5297-2311"
],
[
"tel",
{
"type": "fax"
},
"text",
"+81-3-5297-2312"
],
[
"email",
{},
"text",
"[email protected]"
]
]
]
},
{
"roles": [
"technical",
"administrative"
],
"links": [
{
"value": "https://jpnic.rdap.apnic.net/autnum/2511",
"rel": "related",
"href": "http://whois.nic.ad.jp/cgi-bin/whois_gw?key=TM68535JP/e",
"type": "text/html",
"hreflang": "en"
},
{
"value": "https://jpnic.rdap.apnic.net/autnum/2511",
"rel": "related",
"href": "http://whois.nic.ad.jp/cgi-bin/whois_gw?key=TM68535JP",
"type": "text/html",
"hreflang": "jp"
}
],
"handle": "TM68535JP",
"objectClassName": "entity"
},
{
"roles": [
"abuse"
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2025-09-04T01:00:00Z"
}
],
"links": [
{
"value": "https://jpnic.rdap.apnic.net/autnum/2511",
"rel": "self",
"href": "https://jpnic.rdap.apnic.net/entity/IRT-JPNIC-JP",
"type": "application/rdap+json"
}
],
"remarks": [
{
"description": [
"[email protected] was validated on 2024-11-27"
],
"title": "remarks"
}
],
"handle": "IRT-JPNIC-JP",
"objectClassName": "entity",
"vcardArray": [
"vcard",
[
[
"version",
{},
"text",
"4.0"
],
[
"fn",
{},
"text",
"IRT-JPNIC-JP"
],
[
"kind",
{},
"text",
"group"
],
[
"adr",
{
"label": "Uchikanda OS Bldg 4F, 2-12-6 Uchi-Kanda\nChiyoda-ku, Tokyo 101-0047, japan"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"tel",
{
"type": "voice"
},
"text",
"+81-3-5297-2311"
],
[
"tel",
{
"type": "fax"
},
"text",
"+81-3-5297-2312"
],
[
"email",
{},
"text",
"[email protected]"
],
[
"email",
{
"pref": "1"
},
"text",
"[email protected]"
]
]
]
}
],
"handle": "AS2511",
"startAutnum": 2511,
"endAutnum": 2511,
"objectClassName": "autnum",
"port43": "whois.apnic.net"
} Contact details of private individuals are redacted.