Autonomous System
AS2501 The University of Tokyo
EducationActiveJapanJPNIC
AS2501 (UTnet) is an education network operated by The University of Tokyo in Japan, registered with JPNIC. It has 4 IPv4 prefixes with 200,704 addresses and 2 IPv6 prefixes, which makes it the 1,290th largest of 82,200 active autonomous systems by IPv4 space.
IPv4 addresses200,704in 4 prefixes
IPv6 prefixes2≈ 7.9 × 10²⁸ addresses
Size rank#1,290of 82,200 active ASNs
Details
OrganizationThe University of Tokyo
AS nameUTnet
Websiteu-tokyo.ac.jp
Country Japan (JP)
Network typeEducation
RegistryJPNIC
Abuse contact—
Registered—
Last updated2014-03-19
IPv4 prefixes
4 prefixes · 200,704 addresses| Network | Addresses | First – last address |
|---|---|---|
| 130.69.0.0/16 | 65,536 | 130.69.0.0 – 130.69.255.255 |
| 133.11.0.0/16 | 65,536 | 133.11.0.0 – 133.11.255.255 |
| 157.82.0.0/16 | 65,536 | 157.82.0.0 – 157.82.255.255 |
| 192.51.208.0/20 | 4,096 | 192.51.208.0 – 192.51.223.255 |
130.69.0.0/16 133.11.0.0/16 157.82.0.0/16 192.51.208.0/20
IPv6 prefixes
2 prefixes- 2404:d540::/32
- 2404:d540:1::/48
2404:d540::/32 2404:d540:1::/48
Query AS2501 with the API
The ASN lookup returns everything on this page as JSON, including every prefix. ASN lookups need an API key: a free account comes with 1,000 requests a day.
curl "https://api.ipapi.is/?q=AS2501&key=YOUR_API_KEY"Any address in its prefixes resolves to AS2501, with or without a key:
curl "https://api.ipapi.is/?q=130.69.0.1"Largest networks in Japan
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