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Autonomous systems

AS39521 TNGNET B.V.

Autonomous system AS39521 (TNGNET B.V.): 37 IPv4 networks (20,736 addresses) and 3 IPv6 networks, mostly in Netherlands. Prefix list for firewalls.

AS39521
Organisation
TNGNET B.V.
Countries (share of addresses)
Netherlands 92.6% Switzerland 4.9% Hong Kong SAR China 1.2% New Zealand 1.2%
IPv4 addresses
20,736
IPv4 networks
37
IPv6 networks
3

IPv4 networks 37

IPv6 networks 3

Prefix list for a firewall

Ready-made rules to allow or block the whole of AS39521.

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.