$ query “AS4538” --type=asn → 1 result(s)

AS4538 · ERX-CERNET-BKB

China Education and Research Network Center

AS4538 belongs to China Education and Research Network Center and is a mid-size transit provider, based in China. The system announces a whopping 17.2 million IPv4 addresses (0.46% of routable IPv4 space), including a /12, and supports IPv6. The bulk of its IP address space is in China, with additional presence in Australia and Singapore. Prefix announcements for this AS were recently updated.

  • Top 5% — Top 5% of all autonomous systems by reach and degree
  • Space Overlord — Over 10 million IPv4 addresses

Basic Information

Country
🇨🇳 China
Category
Education/Research
Network Role
Mid-size Transit
Data Origin
Authoritative — Metadata from authoritative RIR registry (ARIN, RIPE, APNIC, etc.)
Last Changed
March 04, 2026
Last Seen
June 22, 2026 (active)

Prefix Summary

IPv4 Prefixes (raw / aggregated)
3 514 / 76
IPv6 Prefixes (raw / aggregated)
9 / 7
IPv4 Addresses
17 174 272
Largest IPv4 Prefix
/12 (1 048 576 addresses)
Largest IPv6 Prefix
/40
Geolocated Countries
🇨🇳 China (29 365 760 IPs), 🇦🇺 Australia (524 288 IPs), 🇸🇬 Singapore (32 IPs)
Prefix Changed
June 23, 2026

Reputation

Reputation
Good — 15 flagged IPs out of 17 174 272 total (0.00%)

Connectivity Summary

Upstream Providers
12 upstreams providing transit
Peers
35 networks exchanging traffic without transit
Downstream Customers
12 downstreams buying transit
Unclassified
4 unclassified BGP neighbors
Degree
63 unique BGP neighbors
Reach
18 networks in customer cone

Upstream Providers (12)

  • AS174 — COGENT (Tier-1 transit)
  • AS1299 — TWELVE99 (Tier-1 transit)
  • AS2914 — NTT-DATA-2914 (Tier-1 transit)
  • AS8359 — MTS
  • AS58453 — CMI-INT-HK
  • AS23764 — CTGNET
  • AS3491 — PCCWG-AS (Tier-1 transit)
  • AS6453 — AS6453 (Tier-1 transit)
  • AS4134 — CHINANET-BACKBONE
  • AS4837 — CHINA169-BACKBONE
  • and 2 more

Prefix Lists

IPv4 Prefixes (3 514 total)

  • 58.192.0.0/12 (1 048 576 addresses (/12 prefix))
  • 222.192.0.0/12 (1 048 576 addresses (/12 prefix))
  • 202.192.0.0/12 (1 048 576 addresses (/12 prefix))
  • 210.32.0.0/12 (1 048 576 addresses (/12 prefix))
  • 59.64.0.0/12 (1 048 576 addresses (/12 prefix))
  • 222.16.0.0/12 (1 048 576 addresses (/12 prefix))
  • 202.112.0.0/13 (524 288 addresses (/13 prefix))
  • 211.80.0.0/13 (524 288 addresses (/13 prefix))
  • 125.216.0.0/13 (524 288 addresses (/13 prefix))
  • 219.224.0.0/13 (524 288 addresses (/13 prefix))
  • 211.64.0.0/13 (524 288 addresses (/13 prefix))
  • 219.216.0.0/13 (524 288 addresses (/13 prefix))
  • 218.192.0.0/13 (524 288 addresses (/13 prefix))
  • 49.52.0.0/14 (262 144 addresses (/14 prefix))
  • 101.4.0.0/14 (262 144 addresses (/14 prefix))
  • 49.120.0.0/14 (262 144 addresses (/14 prefix))
  • 210.28.0.0/14 (262 144 addresses (/14 prefix))
  • 42.244.0.0/14 (262 144 addresses (/14 prefix))
  • 121.192.0.0/14 (262 144 addresses (/14 prefix))
  • 183.172.0.0/14 (262 144 addresses (/14 prefix))
  • 219.244.0.0/14 (262 144 addresses (/14 prefix))
  • 122.204.0.0/14 (262 144 addresses (/14 prefix))
  • 121.248.0.0/14 (262 144 addresses (/14 prefix))
  • 115.24.0.0/14 (262 144 addresses (/14 prefix))
  • 111.186.0.0/15 (131 072 addresses (/15 prefix))
  • 114.212.0.0/15 (131 072 addresses (/15 prefix))
  • 223.128.0.0/15 (131 072 addresses (/15 prefix))
  • 223.2.0.0/15 (131 072 addresses (/15 prefix))
  • 116.56.0.0/15 (131 072 addresses (/15 prefix))
  • 118.202.0.0/15 (131 072 addresses (/15 prefix))
  • 118.228.0.0/15 (131 072 addresses (/15 prefix))
  • 1.184.0.0/15 (131 072 addresses (/15 prefix))
  • 120.94.0.0/15 (131 072 addresses (/15 prefix))
  • 121.48.0.0/15 (131 072 addresses (/15 prefix))
  • 49.140.0.0/15 (131 072 addresses (/15 prefix))
  • 115.154.0.0/15 (131 072 addresses (/15 prefix))
  • 49.208.0.0/15 (131 072 addresses (/15 prefix))
  • 111.116.0.0/15 (131 072 addresses (/15 prefix))
  • 113.54.0.0/15 (131 072 addresses (/15 prefix))
  • 219.242.0.0/15 (131 072 addresses (/15 prefix))
  • 58.154.0.0/15 (131 072 addresses (/15 prefix))
  • 101.76.0.0/15 (131 072 addresses (/15 prefix))
  • 175.186.0.0/15 (131 072 addresses (/15 prefix))
  • 180.84.0.0/15 (131 072 addresses (/15 prefix))
  • 110.64.0.0/15 (131 072 addresses (/15 prefix))
  • 180.208.0.0/15 (131 072 addresses (/15 prefix))
  • 183.168.0.0/15 (131 072 addresses (/15 prefix))
  • 210.26.0.0/15 (131 072 addresses (/15 prefix))
  • 115.156.0.0/15 (131 072 addresses (/15 prefix))
  • 111.114.0.0/15 (131 072 addresses (/15 prefix))

IPv6 Prefixes (9 total)

  • 2001:da8:ff00::/40
  • 2001:daa:2::/47
  • 2001:daa:4::/47
  • 2001:da8:257::/48
  • 2001:daa:1::/48
  • 2001:daa:6::/48
  • 2400:a980:ee::/48