asn.dev

Address space

AS2907 SINET-AS Research Organization of Information and Systems, National Institute of Informatics

Unclassified APNIC

IPv4 prefixes 576 8.77M addresses
IPv6 prefixes 2
Most common size /24 IPv4
Flagged 20

Shape

IPv4 prefix sizes

All IPv4
/15
/15: 16
16
/16
/16: 81
81
/17
/17: 12
12
/18
/18: 20
20
/19
/19: 24
24
/20
/20: 43
43
/21
/21: 52
52
/22
/22: 79
79
/23
/23: 91
91
/24
/24: 138
138
/25
/25: 5
5
/26
/26: 5
5
/27
/27: 2
2
/28
/28: 3
3
/29
/29: 1
1
/30
/30: 1
1
/31
/31: 1
1
/32
/32: 2
2

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

IPv6 prefix sizes

All IPv6
/32
/32: 2
2

Geography

Where the space lands

CountryNamePrefixes
JPJapan578

Review

Flagged prefixes

20 of 578
PrefixFamilyAddressesCountryFlags
192.42.103.0/26IPv464JPToo specific
192.153.95.0/25IPv4128JPToo specific
192.153.95.128/26IPv464JPToo specific
192.153.95.192/26IPv464JPToo specific
202.220.21.0/25IPv4128JPToo specific
202.220.21.128/26IPv464JPToo specific
202.220.21.192/27IPv432JPToo specific
202.220.21.224/28IPv416JPToo specific
202.220.21.240/29IPv48JPToo specific
202.220.21.248/31IPv42JPToo specific
202.220.21.250/32IPv41JPToo specific
202.220.21.251/32IPv41JPToo specific
202.220.21.252/30IPv44JPToo specific
202.236.107.0/26IPv464JPToo specific
202.236.107.64/27IPv432JPToo specific
202.236.107.96/28IPv416JPToo specific
202.236.107.112/28IPv416JPToo specific
202.236.107.128/25IPv4128JPToo specific
202.246.132.0/25IPv4128JPToo specific
202.246.132.128/25IPv4128JPToo specific

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