Autonomous System

AS4538 China Education and Research Network Center

ISPActiveChinaAPNIC

AS4538 (ERX-CERNET-BKB) is an ISP network operated by China Education and Research Network Center in China, registered with APNIC. It has 5,039 IPv4 prefixes with 42,256,896 addresses and 4,990 IPv6 prefixes, which makes it the 15th largest of 82,283 active autonomous systems by IPv4 space.

IPv4 addresses42,256,896in 5,039 prefixes
IPv6 prefixes4,990≈ 3.3 × 10³² addresses
Size rank#15of 82,283 active ASNs
Abuser scoreVery Low0.01% of its addresses flagged · method

Details

OrganizationChina Education and Research Network Center
AS nameERX-CERNET-BKB
Websitecernet.edu.cn
Country China (CN)
Network typeISP
RegistryAPNIC
Abuse contactabuse@cernet.edu.cn
Registered—
Last updated2025-10-31

IPv4 prefixes

5,039 prefixes · 42,256,896 addresses
NetworkAddressesFirst – last address
58.192.0.0/121,048,57658.192.0.0 – 58.207.255.255
59.64.0.0/121,048,57659.64.0.0 – 59.79.255.255
202.192.0.0/121,048,576202.192.0.0 – 202.207.255.255
210.32.0.0/121,048,576210.32.0.0 – 210.47.255.255
222.16.0.0/121,048,576222.16.0.0 – 222.31.255.255
222.192.0.0/121,048,576222.192.0.0 – 222.207.255.255
58.200.0.0/13524,28858.200.0.0 – 58.207.255.255
125.216.0.0/13524,288125.216.0.0 – 125.223.255.255
202.112.0.0/13524,288202.112.0.0 – 202.119.255.255
202.200.0.0/13524,288202.200.0.0 – 202.207.255.255
211.64.0.0/13524,288211.64.0.0 – 211.71.255.255
211.80.0.0/13524,288211.80.0.0 – 211.87.255.255
218.192.0.0/13524,288218.192.0.0 – 218.199.255.255
219.216.0.0/13524,288219.216.0.0 – 219.223.255.255
219.224.0.0/13524,288219.224.0.0 – 219.231.255.255
222.16.0.0/13524,288222.16.0.0 – 222.23.255.255
222.24.0.0/13524,288222.24.0.0 – 222.31.255.255
49.52.0.0/14262,14449.52.0.0 – 49.55.255.255
49.120.0.0/14262,14449.120.0.0 – 49.123.255.255
59.64.0.0/14262,14459.64.0.0 – 59.67.255.255
101.4.0.0/14262,144101.4.0.0 – 101.7.255.255
115.24.0.0/14262,144115.24.0.0 – 115.27.255.255
121.192.0.0/14262,144121.192.0.0 – 121.195.255.255
121.248.0.0/14262,144121.248.0.0 – 121.251.255.255
122.204.0.0/14262,144122.204.0.0 – 122.207.255.255
The 25 largest of 5,039. The API and the database have all of them.

IPv6 prefixes

4,990 prefixes
  • 2001:252::/32
  • 2401:cc00::/32
  • 2401:ec00::/32
  • 2402:2000::/32
  • 2402:e740::/32
  • 2402:f000::/32
  • 2403:3140::/32
  • 2403:8c00::/32
  • 2403:ac00::/32
  • 2403:d400::/32
  • 2405:d900::/32
  • 2406:3340::/32
  • 240a:a000::/32
  • 240a:a001::/32
  • 240a:a002::/32
  • 240a:a003::/32
  • 240a:a004::/32
  • 240a:a005::/32
  • 240a:a006::/32
  • 240a:a007::/32
  • 240a:a008::/32
  • 240a:a009::/32
  • 240a:a00a::/32
  • 240a:a00b::/32
  • 240a:a00c::/32
The 25 largest of 4,990. The API and the database have all of them.

Query AS4538 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=AS4538&key=YOUR_API_KEY"

Any address in its prefixes resolves to AS4538, with or without a key:

curl "https://api.ipapi.is/?q=58.192.0.1"

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