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Autonomous systems

AS17621 China Unicom Shanghai network

Autonomous system AS17621 (China Unicom Shanghai network): 345 IPv4 networks (837,632 addresses) and 66 IPv6 networks, mostly in China. Prefix list for firewalls.

AS17621
Organisation
China Unicom Shanghai network
Countries (share of addresses)
China 99.2% Germany 0.8%
IPv4 addresses
837,632
IPv4 networks
345
IPv6 networks
66

IPv4 networks 345

Show 297 more

IPv6 networks 66

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Prefix list for a firewall

Ready-made rules to allow or block the whole of AS17621.

What an autonomous system is

An autonomous system (AS) is the set of IP networks run by one organisation under a single routing policy. Providers, hosts and large companies announce their networks to the internet over BGP under their own AS number. With the number you can find all of an organisation’s addresses, for example to allow a service through a firewall or to block traffic from a network.

Network and country data come from DB-IP and are refreshed monthly. The country shows where addresses are used, not where the company is registered.