asn.dev

Address space

AS2523 ITRC-NET Internet Technology Research Consortium

IPv4 prefixes 18 61.94K addresses
IPv6 prefixes 1
Most common size /23 IPv4
Flagged 5

Shape

Prefix sizes

IPv4
/17
/17: 1
1
/19
/19: 2
2
/20
/20: 2
2
/22
/22: 2
2
/23
/23: 3
3
/24
/24: 3
3
/25
/25: 1
1
/26
/26: 1
1
/27
/27: 1
1
/28
/28: 1
1
/29
/29: 1
1

How this network carves its IPv4 space. A wall of /24s usually means many small customer assignments or fine-grained traffic engineering; a few short prefixes means large contiguous allocations announced whole.

Shape

Prefix sizes

IPv6
/32
/32: 1
1

Geography

Where the space lands

CountryNamePrefixes
JPJapan19

Review

Flagged prefixes

5 of 19
PrefixFamilyAddressesCountryFlags
133.69.167.0/25IPv4128JPToo specific
133.69.167.128/26IPv464JPToo specific
133.69.167.192/27IPv432JPToo specific
133.69.167.224/28IPv416JPToo specific
133.69.167.240/29IPv48JPToo specific

A flag is an observation, not an accusation. Very large and very specific prefixes are both legitimate in the right context.

Inventory

All prefixes

19 total
PrefixFamilyAddressesCountryFlags
133.69.0.0/17IPv432,768JP
133.69.128.0/19IPv48,192JP
133.69.164.0/23IPv4512JP
133.69.166.0/24IPv4256JP
133.69.167.0/25IPv4128JPToo specific
133.69.167.128/26IPv464JPToo specific
133.69.167.192/27IPv432JPToo specific
133.69.167.224/28IPv416JPToo specific
133.69.167.240/29IPv48JPToo specific
133.69.177.0/24IPv4256JP
133.69.178.0/23IPv4512JP
133.69.180.0/22IPv41,024JP
133.69.185.0/24IPv4256JP
133.69.186.0/23IPv4512JP
133.69.188.0/22IPv41,024JP
133.69.192.0/20IPv44,096JP
133.69.208.0/20IPv44,096JP
133.69.224.0/19IPv48,192JP
2407:e0c0::/32IPv6JP