asn.dev

Address space

AS4538 ERX-CERNET-BKB China Education and Research Network Center

IPv4 prefixes 3,361 16.28M addresses
IPv6 prefixes 6
Most common size /24 IPv4
Flagged 3

Shape

Prefix sizes

IPv4
/15
/15: 10
10
/16
/16: 31
31
/17
/17: 88
88
/18
/18: 213
213
/19
/19: 330
330
/20
/20: 461
461
/21
/21: 483
483
/22
/22: 510
510
/23
/23: 557
557
/24
/24: 675
675
/25
/25: 1
1
/26
/26: 1
1
/27
/27: 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
/47
/47: 2
2
/48
/48: 4
4

Geography

Where the space lands

CountryNamePrefixes
CNChina3,367

Review

Flagged prefixes

3 of 3,367
PrefixFamilyAddressesCountryFlags
202.38.140.32/27IPv432CNToo specific
202.38.140.64/26IPv464CNToo specific
202.38.140.128/25IPv4128CNToo 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

showing 400 of 3,367
PrefixFamilyAddressesCountryFlags
1.51.0.0/22IPv41,024CN
1.51.4.0/22IPv41,024CN
1.51.8.0/21IPv42,048CN
1.51.16.0/20IPv44,096CN
1.51.56.0/21IPv42,048CN
1.51.64.0/18IPv416,384CN
1.51.128.0/17IPv432,768CN
1.184.0.0/15IPv4131,072CN
42.244.0.0/16IPv465,536CN
42.245.0.0/17IPv432,768CN
42.245.128.0/18IPv416,384CN
42.246.0.0/16IPv465,536CN
42.247.0.0/22IPv41,024CN
42.247.4.0/23IPv4512CN
42.247.6.0/23IPv4512CN
42.247.8.0/21IPv42,048CN
42.247.16.0/22IPv41,024CN
42.247.20.0/24IPv4256CN
42.247.21.0/24IPv4256CN
42.247.22.0/23IPv4512CN
42.247.24.0/21IPv42,048CN
42.247.32.0/20IPv44,096CN
42.247.48.0/22IPv41,024CN
42.247.52.0/23IPv4512CN
42.247.54.0/23IPv4512CN
42.247.56.0/23IPv4512CN
42.247.58.0/24IPv4256CN
42.247.59.0/24IPv4256CN
42.247.60.0/22IPv41,024CN
42.247.64.0/19IPv48,192CN
42.247.96.0/21IPv42,048CN
42.247.104.0/22IPv41,024CN
42.247.108.0/22IPv41,024CN
42.247.112.0/23IPv4512CN
42.247.114.0/23IPv4512CN
42.247.116.0/22IPv41,024CN
42.247.120.0/21IPv42,048CN
42.247.128.0/17IPv432,768CN
49.52.0.0/19IPv48,192CN
49.52.32.0/20IPv44,096CN
49.52.48.0/24IPv4256CN
49.52.49.0/24IPv4256CN
49.52.50.0/23IPv4512CN
49.52.52.0/22IPv41,024CN
49.52.56.0/21IPv42,048CN
49.52.64.0/18IPv416,384CN
49.52.128.0/17IPv432,768CN
49.53.0.0/16IPv465,536CN
49.54.0.0/15IPv4131,072CN
49.120.0.0/18IPv416,384CN
49.120.64.0/19IPv48,192CN
49.120.96.0/19IPv48,192CN
49.120.128.0/17IPv432,768CN
49.121.0.0/16IPv465,536CN
49.122.0.0/18IPv416,384CN
49.122.64.0/22IPv41,024CN
49.122.68.0/22IPv41,024CN
49.122.72.0/21IPv42,048CN
49.122.80.0/20IPv44,096CN
49.122.96.0/19IPv48,192CN
49.122.128.0/18IPv416,384CN
49.122.192.0/18IPv416,384CN
49.123.0.0/17IPv432,768CN
49.123.128.0/17IPv432,768CN
49.141.0.0/19IPv48,192CN
49.141.32.0/20IPv44,096CN
49.141.48.0/20IPv44,096CN
49.141.64.0/18IPv416,384CN
49.141.128.0/20IPv44,096CN
49.141.144.0/21IPv42,048CN
49.141.152.0/21IPv42,048CN
49.141.160.0/19IPv48,192CN
49.141.192.0/20IPv44,096CN
49.141.208.0/23IPv4512CN
49.141.210.0/24IPv4256CN
49.141.211.0/24IPv4256CN
49.141.212.0/22IPv41,024CN
49.141.216.0/21IPv42,048CN
49.141.224.0/19IPv48,192CN
49.208.0.0/15IPv4131,072CN
58.154.0.0/20IPv44,096CN
58.154.32.0/23IPv4512CN
58.154.34.0/24IPv4256CN
58.154.35.0/24IPv4256CN
58.154.36.0/23IPv4512CN
58.154.38.0/23IPv4512CN
58.154.40.0/21IPv42,048CN
58.154.48.0/20IPv44,096CN
58.154.64.0/19IPv48,192CN
58.154.96.0/20IPv44,096CN
58.154.112.0/20IPv44,096CN
58.154.128.0/17IPv432,768CN
58.155.0.0/19IPv48,192CN
58.155.32.0/20IPv44,096CN
58.155.48.0/22IPv41,024CN
58.155.52.0/23IPv4512CN
58.155.54.0/23IPv4512CN
58.155.56.0/21IPv42,048CN
58.155.64.0/21IPv42,048CN
58.155.72.0/21IPv42,048CN
58.155.80.0/20IPv44,096CN
58.155.96.0/20IPv44,096CN
58.155.112.0/20IPv44,096CN
58.155.128.0/20IPv44,096CN
58.155.144.0/22IPv41,024CN
58.155.148.0/22IPv41,024CN
58.155.152.0/21IPv42,048CN
58.155.160.0/19IPv48,192CN
58.155.192.0/18IPv416,384CN
58.192.0.0/15IPv4131,072CN
58.194.0.0/21IPv42,048CN
58.194.8.0/23IPv4512CN
58.194.10.0/23IPv4512CN
58.194.12.0/22IPv41,024CN
58.194.16.0/20IPv44,096CN
58.194.32.0/19IPv48,192CN
58.194.64.0/18IPv416,384CN
58.194.128.0/18IPv416,384CN
58.194.192.0/18IPv416,384CN
58.195.0.0/18IPv416,384CN
58.195.64.0/19IPv48,192CN
58.195.96.0/23IPv4512CN
58.195.98.0/23IPv4512CN
58.195.100.0/22IPv41,024CN
58.195.104.0/21IPv42,048CN
58.195.112.0/20IPv44,096CN
58.195.128.0/17IPv432,768CN
58.196.0.0/17IPv432,768CN
58.196.128.0/19IPv48,192CN
58.196.160.0/20IPv44,096CN
58.196.176.0/23IPv4512CN
58.196.178.0/24IPv4256CN
58.196.179.0/24IPv4256CN
58.196.180.0/22IPv41,024CN
58.196.184.0/21IPv42,048CN
58.196.192.0/18IPv416,384CN
58.197.0.0/16IPv465,536CN
58.198.0.0/15IPv4131,072CN
58.200.0.0/23IPv4512CN
58.200.2.0/24IPv4256CN
58.200.3.0/24IPv4256CN
58.200.4.0/24IPv4256CN
58.200.5.0/24IPv4256CN
58.200.6.0/24IPv4256CN
58.200.7.0/24IPv4256CN
58.200.8.0/23IPv4512CN
58.200.10.0/24IPv4256CN
58.200.11.0/24IPv4256CN
58.200.12.0/22IPv41,024CN
58.200.16.0/22IPv41,024CN
58.200.20.0/23IPv4512CN
58.200.22.0/24IPv4256CN
58.200.23.0/24IPv4256CN
58.200.24.0/21IPv42,048CN
58.200.32.0/19IPv48,192CN
58.200.64.0/22IPv41,024CN
58.200.68.0/24IPv4256CN
58.200.69.0/24IPv4256CN
58.200.70.0/23IPv4512CN
58.200.72.0/22IPv41,024CN
58.200.76.0/23IPv4512CN
58.200.78.0/23IPv4512CN
58.200.80.0/21IPv42,048CN
58.200.88.0/22IPv41,024CN
58.200.92.0/23IPv4512CN
58.200.94.0/23IPv4512CN
58.200.96.0/23IPv4512CN
58.200.98.0/23IPv4512CN
58.200.100.0/22IPv41,024CN
58.200.104.0/21IPv42,048CN
58.200.112.0/23IPv4512CN
58.200.114.0/24IPv4256CN
58.200.115.0/24IPv4256CN
58.200.116.0/23IPv4512CN
58.200.118.0/23IPv4512CN
58.200.120.0/22IPv41,024CN
58.200.124.0/23IPv4512CN
58.200.126.0/23IPv4512CN
58.200.128.0/21IPv42,048CN
58.200.136.0/22IPv41,024CN
58.200.140.0/23IPv4512CN
58.200.142.0/23IPv4512CN
58.200.144.0/20IPv44,096CN
58.200.160.0/19IPv48,192CN
58.200.192.0/20IPv44,096CN
58.200.208.0/21IPv42,048CN
58.200.216.0/22IPv41,024CN
58.200.220.0/22IPv41,024CN
58.200.224.0/20IPv44,096CN
58.200.240.0/21IPv42,048CN
58.200.248.0/22IPv41,024CN
58.200.252.0/23IPv4512CN
58.200.254.0/23IPv4512CN
58.201.0.0/16IPv465,536CN
58.202.0.0/15IPv4131,072CN
58.204.0.0/16IPv465,536CN
58.205.0.0/17IPv432,768CN
58.205.128.0/18IPv416,384CN
58.205.192.0/22IPv41,024CN
58.205.196.0/23IPv4512CN
58.205.198.0/23IPv4512CN
58.205.200.0/21IPv42,048CN
58.205.208.0/22IPv41,024CN
58.205.212.0/23IPv4512CN
58.205.214.0/23IPv4512CN
58.205.216.0/21IPv42,048CN
58.205.224.0/19IPv48,192CN
58.206.0.0/19IPv48,192CN
58.206.32.0/19IPv48,192CN
58.206.64.0/18IPv416,384CN
58.206.128.0/21IPv42,048CN
58.206.136.0/21IPv42,048CN
58.206.144.0/20IPv44,096CN
58.206.160.0/19IPv48,192CN
58.207.0.0/16IPv465,536CN
59.64.0.0/20IPv44,096CN
59.64.16.0/24IPv4256CN
59.64.17.0/24IPv4256CN
59.64.18.0/23IPv4512CN
59.64.20.0/22IPv41,024CN
59.64.24.0/21IPv42,048CN
59.64.32.0/19IPv48,192CN
59.64.64.0/19IPv48,192CN
59.64.96.0/20IPv44,096CN
59.64.112.0/21IPv42,048CN
59.64.120.0/22IPv41,024CN
59.64.124.0/23IPv4512CN
59.64.126.0/24IPv4256CN
59.64.127.0/24IPv4256CN
59.64.128.0/17IPv432,768CN
59.65.0.0/17IPv432,768CN
59.65.128.0/18IPv416,384CN
59.65.192.0/21IPv42,048CN
59.65.200.0/21IPv42,048CN
59.65.208.0/20IPv44,096CN
59.65.224.0/20IPv44,096CN
59.65.240.0/20IPv44,096CN
59.66.0.0/16IPv465,536CN
59.67.0.0/21IPv42,048CN
59.67.8.0/21IPv42,048CN
59.67.16.0/20IPv44,096CN
59.67.32.0/19IPv48,192CN
59.67.64.0/18IPv416,384CN
59.67.128.0/22IPv41,024CN
59.67.132.0/23IPv4512CN
59.67.134.0/23IPv4512CN
59.67.136.0/21IPv42,048CN
59.67.144.0/20IPv44,096CN
59.67.160.0/20IPv44,096CN
59.67.176.0/21IPv42,048CN
59.67.184.0/21IPv42,048CN
59.67.192.0/22IPv41,024CN
59.67.196.0/22IPv41,024CN
59.67.200.0/21IPv42,048CN
59.67.208.0/21IPv42,048CN
59.67.216.0/22IPv41,024CN
59.67.220.0/23IPv4512CN
59.67.222.0/23IPv4512CN
59.67.224.0/19IPv48,192CN
59.68.0.0/18IPv416,384CN
59.68.64.0/19IPv48,192CN
59.68.96.0/20IPv44,096CN
59.68.112.0/23IPv4512CN
59.68.114.0/23IPv4512CN
59.68.116.0/22IPv41,024CN
59.68.120.0/21IPv42,048CN
59.68.128.0/18IPv416,384CN
59.68.192.0/19IPv48,192CN
59.68.224.0/21IPv42,048CN
59.68.232.0/23IPv4512CN
59.68.234.0/23IPv4512CN
59.68.236.0/22IPv41,024CN
59.68.240.0/20IPv44,096CN
59.69.0.0/17IPv432,768CN
59.69.128.0/18IPv416,384CN
59.69.192.0/19IPv48,192CN
59.69.224.0/19IPv48,192CN
59.70.0.0/19IPv48,192CN
59.70.32.0/22IPv41,024CN
59.70.36.0/24IPv4256CN
59.70.37.0/24IPv4256CN
59.70.38.0/23IPv4512CN
59.70.40.0/21IPv42,048CN
59.70.48.0/24IPv4256CN
59.70.49.0/24IPv4256CN
59.70.50.0/23IPv4512CN
59.70.52.0/22IPv41,024CN
59.70.56.0/21IPv42,048CN
59.70.64.0/18IPv416,384CN
59.70.128.0/21IPv42,048CN
59.70.136.0/21IPv42,048CN
59.70.144.0/20IPv44,096CN
59.70.160.0/19IPv48,192CN
59.70.192.0/18IPv416,384CN
59.71.0.0/19IPv48,192CN
59.71.32.0/20IPv44,096CN
59.71.48.0/21IPv42,048CN
59.71.56.0/22IPv41,024CN
59.71.60.0/22IPv41,024CN
59.71.64.0/19IPv48,192CN
59.71.96.0/23IPv4512CN
59.71.98.0/23IPv4512CN
59.71.100.0/22IPv41,024CN
59.71.104.0/21IPv42,048CN
59.71.112.0/20IPv44,096CN
59.71.128.0/17IPv432,768CN
59.72.0.0/17IPv432,768CN
59.72.128.0/18IPv416,384CN
59.72.192.0/24IPv4256CN
59.72.193.0/24IPv4256CN
59.72.194.0/23IPv4512CN
59.72.196.0/22IPv41,024CN
59.72.200.0/21IPv42,048CN
59.72.208.0/20IPv44,096CN
59.72.224.0/21IPv42,048CN
59.72.232.0/21IPv42,048CN
59.72.240.0/20IPv44,096CN
59.73.0.0/20IPv44,096CN
59.73.16.0/21IPv42,048CN
59.73.24.0/21IPv42,048CN
59.73.32.0/19IPv48,192CN
59.73.64.0/18IPv416,384CN
59.73.168.0/21IPv42,048CN
59.73.176.0/20IPv44,096CN
59.73.192.0/19IPv48,192CN
59.73.224.0/19IPv48,192CN
59.74.0.0/19IPv48,192CN
59.74.32.0/22IPv41,024CN
59.74.36.0/23IPv4512CN
59.74.38.0/23IPv4512CN
59.74.40.0/22IPv41,024CN
59.74.44.0/23IPv4512CN
59.74.46.0/24IPv4256CN
59.74.47.0/24IPv4256CN
59.74.48.0/23IPv4512CN
59.74.50.0/24IPv4256CN
59.74.51.0/24IPv4256CN
59.74.52.0/22IPv41,024CN
59.74.56.0/22IPv41,024CN
59.74.60.0/23IPv4512CN
59.74.62.0/23IPv4512CN
59.74.64.0/18IPv416,384CN
59.74.128.0/20IPv44,096CN
59.74.144.0/20IPv44,096CN
59.74.160.0/19IPv48,192CN
59.74.192.0/19IPv48,192CN
59.74.224.0/20IPv44,096CN
59.74.240.0/21IPv42,048CN
59.74.248.0/24IPv4256CN
59.74.249.0/24IPv4256CN
59.74.250.0/23IPv4512CN
59.74.252.0/22IPv41,024CN
59.75.0.0/22IPv41,024CN
59.75.4.0/22IPv41,024CN
59.75.8.0/21IPv42,048CN
59.75.16.0/20IPv44,096CN
59.75.32.0/20IPv44,096CN
59.75.48.0/22IPv41,024CN
59.75.52.0/23IPv4512CN
59.75.54.0/23IPv4512CN
59.75.56.0/23IPv4512CN
59.75.58.0/23IPv4512CN
59.75.60.0/22IPv41,024CN
59.75.64.0/18IPv416,384CN
59.75.128.0/21IPv42,048CN
59.75.136.0/22IPv41,024CN
59.75.140.0/23IPv4512CN
59.75.142.0/24IPv4256CN
59.75.143.0/24IPv4256CN
59.75.144.0/22IPv41,024CN
59.75.148.0/23IPv4512CN
59.75.150.0/23IPv4512CN
59.75.152.0/21IPv42,048CN
59.75.160.0/20IPv44,096CN
59.75.176.0/24IPv4256CN
59.75.177.0/24IPv4256CN
59.75.178.0/23IPv4512CN
59.75.180.0/22IPv41,024CN
59.75.184.0/21IPv42,048CN
59.75.192.0/24IPv4256CN
59.75.193.0/24IPv4256CN
59.75.194.0/23IPv4512CN
59.75.196.0/22IPv41,024CN
59.75.200.0/21IPv42,048CN
59.75.208.0/24IPv4256CN
59.75.209.0/24IPv4256CN
59.75.210.0/23IPv4512CN
59.75.212.0/22IPv41,024CN
59.75.216.0/21IPv42,048CN
59.75.224.0/20IPv44,096CN
59.75.240.0/21IPv42,048CN
59.75.248.0/21IPv42,048CN
59.76.0.0/18IPv416,384CN
59.76.64.0/19IPv48,192CN
59.76.96.0/21IPv42,048CN
59.76.104.0/21IPv42,048CN
59.76.112.0/20IPv44,096CN
59.76.128.0/19IPv48,192CN
59.76.160.0/20IPv44,096CN
59.76.176.0/21IPv42,048CN

Capped at 400 rows to keep the page a sane size. The filter searches only what is rendered.