asn.dev

Address space

AS5653 UCSF

Education ARIN

IPv4 prefixes 49 196K addresses
IPv6 prefixes 3
Most common size /24 IPv4
Flagged 7

Shape

IPv4 prefix sizes

All IPv4
/16
/16: 1
1
/18
/18: 3
3
/19
/19: 4
4
/20
/20: 6
6
/21
/21: 5
5
/22
/22: 7
7
/23
/23: 7
7
/24
/24: 12
12
/25
/25: 1
1
/29
/29: 2
2
/31
/31: 1
1

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
/121
/121: 2
2
/123
/123: 1
1

Geography

Where the space lands

CountryNamePrefixes
USUnited States of America52

Review

Flagged prefixes

7 of 52
PrefixFamilyAddressesCountryFlags
137.164.3.112/29IPv48USToo specific
137.164.3.136/29IPv48USToo specific
137.164.23.152/31IPv42USToo specific
205.154.255.128/25IPv4128USToo specific
2607:f380::118:9a40:3700/121IPv6/121USToo specific
2607:f380::118:9a40:3880/121IPv6/121USToo specific
2607:f380:1::118:9a41:7980/123IPv6/123USToo specific

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