Autonomous System

AS23780 CTB Media Inc.

ISPActiveJapanAPNIC

AS23780 (CTB) is an ISP network operated by CTB Media Inc. in Japan, registered with APNIC. It has 5 IPv4 prefixes with 16,384 addresses and 1 IPv6 prefix, which makes it the 7,785th largest of 82,200 active autonomous systems by IPv4 space.

IPv4 addresses16,384in 5 prefixes

IPv6 prefixes1≈ 7.9 × 10²⁸ addresses

Size rank#7,785of 82,200 active ASNs

Abuser scoreLow0.22% of its addresses flagged · method

Details

OrganizationCTB Media Inc.

AS nameCTB

Websitectb.ne.jp

Country Japan (JP)

Network typeISP

RegistryAPNIC

Abuse contacthostmaster@nic.ad.jp

Registered—

Last updated2024-08-16

IPv4 prefixes

5 prefixes · 16,384 addresses

Network	Addresses	First – last address
211.19.224.0/19	8,192	211.19.224.0 – 211.19.255.255
211.15.112.0/20	4,096	211.15.112.0 – 211.15.127.255
49.128.24.0/21	2,048	49.128.24.0 – 49.128.31.255
49.128.96.0/22	1,024	49.128.96.0 – 49.128.99.255
203.201.52.0/22	1,024	203.201.52.0 – 203.201.55.255

211.19.224.0/19
211.15.112.0/20
49.128.24.0/21
49.128.96.0/22
203.201.52.0/22

IPv6 prefixes

1 prefix

2402:6c80::/32

2402:6c80::/32

Query AS23780 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=AS23780&key=YOUR_API_KEY"

Any address in its prefixes resolves to AS23780, with or without a key:

curl "https://api.ipapi.is/?q=211.19.224.1"

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