Autonomous system
AS7497 CSTNET-AS-AP Computer Network Information Center of Chinese Academy of Sciences CNIC-CAS
Education APNIC
Summary
CSTNET — China Science and Technology Network (CNIC-CAS)
education research legacy
CSTNET-AS-AP is CSTNET, the China Science and Technology Network, run by the Computer Network Information Center of the Chinese Academy of Sciences (CNIC-CAS). It is one of China's national research and education networks.
What it's used for
- Connecting the institutes of the Chinese Academy of Sciences, national research institutes, scientific data centres and a large share of China's national research infrastructure. It is an academic, non-profit network, not a commercial ISP.
- Carrying research traffic internationally: CSTNET maintains open exchange points in China and the United States and links to peer research networks in Europe and the Asia-Pacific.
Notable
- By far the largest network in its numeric neighbourhood — roughly 860,000 IPv4 addresses across several hundred prefixes, plus a substantial IPv6 footprint. Every prefix checked registers back to
CSTNET-CNunder CNIC-CAS, so the space really is all one institution's. - The classic block is
159.226.0.0/16, the Chinese Academy of Sciences' Class B, alongside ranges in124.16/15,210.72,210.77and202.127. - Its footprint is institutional rather than residential: universities, institutes and data centres, not subscriber pools.
Interesting
- CSTNET is generally credited as the birthplace of the Internet in China — the Chinese Academy of Sciences ran the country's first full TCP/IP connection to the global Internet. The network still carries the research community it was built for.
This description is AI-generated, best-effort context — not authoritative, and provided without any guarantee of accuracy. Source, and how to suggest an edit.
Interconnection
Peering at a glance
Internet exchanges
Recorded at 1 exchange in 1 country, largest first.
| Exchange | Location | Their address |
|---|---|---|
| Hong Kong Internet Exchange | Hong Kong, China | 123.255.91.238 |
Transit providers
13 upstream, 5 downstream and 28 adjacent networks observed; most-used upstreams first.
Exchange presence is recorded rather than inferred: the directory collected by Packet Clearing House (https://www.pch.net/ixp/data) on 2026-10-10, licensed CC BY-NC-SA 3.0. Transit is inferred from observed BGP paths, never declared by either party.
Address space
Summary
IPv4 319 prefixes · 868K addresses IPv6 221 prefixes
| Country | Name | Prefixes |
|---|---|---|
| CN | China | 540 |
Registry
Allocation record
- Registry
- APNIC
- Handle
AS7497- Registry name
- CSTNET-AS-AP
- Registrant
- CNIC-CAS
- Abuse contact
- abuse-ip@cstnet.cn
- Registered
- 2023-10-09
- Last changed
- 2023-10-09
- Allocation
- allocated
Declared
PeeringDB profile
- Name
- Computer Network Information Center of Chinese Academy of Sciences (CNIC-CAS)
- Scope
- Not Disclosed
- Traffic ratio
- Not Disclosed
- Peering policy
- Open
- Website
- http://cnic.cn
PeeringDB records are maintained by the network operator and are not independently verified. Treat them as a statement of intent rather than of fact. For the observed and recorded view, see peering, which lists the exchanges Packet Clearing House has a port on file for.
Routing security
RPKI and IRR
- RPKI
- 99.5% valid · 632 valid, 3 with no ROA
- ROAs
- 1,032 authorising AS7497
- ASPA
- no ASPA record
- IRR
- 99.8% registered · 634 of 635 announcements 1 other origin
- Route objects
- 251 naming AS7497
Reputation
Classification and threat
Education University, school or national research and education network.
Spamhaus DROP
Not on ASN-DROP The network as a whole is not listed.
No DROP prefixes None of its announced space is on the DROP prefix list.
Spamhaus DROP ("Don't Route Or Peer") lists space and networks run by, or hijacked for, spam and cybercrime operations: 431 networks and 1,775 prefixes, as published 2026-10-11. A short, high-confidence list, so a match is worth taking seriously, and absence from it says little on its own.
FBI IC3
No IC3 indicators Nothing from the FBI IC3 feed.
IC3 threat data is alpha. Absence of an indicator is not evidence of good behaviour, only of absence from this one feed.
Elsewhere