$ query “AS4538” --type=asn → 1 result(s)
AS4538 — ERX-CERNET-BKB
China Education and Research Network Center
AS4538 is a mid-size transit provider operated by China Education and Research Network Center, registered in China. The network announces a whopping 17.2 million IPv4 addresses (0.46% of routable IPv4 space), including a /12. Supports IPv6.
- Top 5% — Top 5% of all autonomous systems by reach and degree
- Space Overlord — Over 10 million IPv4 addresses
- #5 in China — Top 10 by reach within country
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
- March 04, 2026
Prefix Summary
- IPv4 Prefixes (raw / aggregated)
- 5 136 / 78
- IPv6 Prefixes (raw / aggregated)
- 7 / 5
- IPv4 Addresses
- 17 176 832
- Largest IPv4 Prefix
- /12 (1 048 576 addresses)
- Largest IPv6 Prefix
- /47
- Geolocated Countries
- 🇨🇳 CN (139 IPs), 🇦🇺 AU (3 IPs)
- Prefix Changed
- March 04, 2026
Reputation
- Reputation
- Good — 13 flagged IPs out of 17 176 832 total (0.00%)
Connectivity Summary
- Upstream Providers
- 11 upstream autonomous systems providing transit
- Peers
- 36 autonomous systems exchanging traffic without transit fees
- Downstream Customers
- 12 downstream autonomous systems buying transit
- Degree
- 61 unique BGP neighbors (providers + customers + peers)
- Reach
- 1 730 — customer cone size measuring network influence
- Degree Rank
- #2 593
- Reach Rank
- #643
- Country Rank
- #5
Upstream Providers (11)
- AS174 — COGENT-174 (Tier-1 transit)
- AS1299 — TWELVE99 (Tier-1 transit)
- AS2914 — NTT-DATA-2914 (Tier-1 transit)
- AS23764 — CTGNET
- AS58453 — CMI-INT-HK
- AS3491 — CONSOLE-CONNECT-ASN (Tier-1 transit)
- AS6453 — AS6453 (Tier-1 transit)
- AS4134 — CHINANET-BACKBONE
- AS4837 — CHINA169-BACKBONE
- AS140570 — HKBCS-AS-AP
- and 1 more
Prefix Lists
IPv4 Prefixes (5 136 total)
- 58.192.0.0/12 (1 048 576 addresses)
- 59.64.0.0/12 (1 048 576 addresses)
- 202.192.0.0/12 (1 048 576 addresses)
- 210.32.0.0/12 (1 048 576 addresses)
- 222.16.0.0/12 (1 048 576 addresses)
- 222.192.0.0/12 (1 048 576 addresses)
- 125.216.0.0/13 (524 288 addresses)
- 202.112.0.0/13 (524 288 addresses)
- 211.64.0.0/13 (524 288 addresses)
- 211.80.0.0/13 (524 288 addresses)
- 218.192.0.0/13 (524 288 addresses)
- 219.216.0.0/13 (524 288 addresses)
- 219.224.0.0/13 (524 288 addresses)
- 42.244.0.0/14 (262 144 addresses)
- 49.52.0.0/14 (262 144 addresses)
- 49.120.0.0/14 (262 144 addresses)
- 101.4.0.0/14 (262 144 addresses)
- 115.24.0.0/14 (262 144 addresses)
- 121.192.0.0/14 (262 144 addresses)
- 121.248.0.0/14 (262 144 addresses)
- 122.204.0.0/14 (262 144 addresses)
- 183.172.0.0/14 (262 144 addresses)
- 210.28.0.0/14 (262 144 addresses)
- 219.244.0.0/14 (262 144 addresses)
- 1.184.0.0/15 (131 072 addresses)
- 49.140.0.0/15 (131 072 addresses)
- 49.208.0.0/15 (131 072 addresses)
- 58.154.0.0/15 (131 072 addresses)
- 101.76.0.0/15 (131 072 addresses)
- 110.64.0.0/15 (131 072 addresses)
- 111.114.0.0/15 (131 072 addresses)
- 111.116.0.0/15 (131 072 addresses)
- 111.186.0.0/15 (131 072 addresses)
- 113.54.0.0/15 (131 072 addresses)
- 114.212.0.0/15 (131 072 addresses)
- 115.154.0.0/15 (131 072 addresses)
- 115.156.0.0/15 (131 072 addresses)
- 116.56.0.0/15 (131 072 addresses)
- 118.202.0.0/15 (131 072 addresses)
- 118.228.0.0/15 (131 072 addresses)
- 120.94.0.0/15 (131 072 addresses)
- 121.48.0.0/15 (131 072 addresses)
- 175.186.0.0/15 (131 072 addresses)
- 180.84.0.0/15 (131 072 addresses)
- 180.208.0.0/15 (131 072 addresses)
- 183.168.0.0/15 (131 072 addresses)
- 202.120.0.0/15 (131 072 addresses)
- 210.26.0.0/15 (131 072 addresses)
- 219.242.0.0/15 (131 072 addresses)
- 223.2.0.0/15 (131 072 addresses)
IPv6 Prefixes (7 total)
- 2001:daa:2::/47
- 2001:daa:4::/47
- 2001:da8:257::/48
- 2001:daa:1::/48
- 2001:daa:6::/48