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Autonomous systems

AS13205 British Telecommunications PLC

Autonomous system AS13205 (British Telecommunications PLC): 4 IPv4 networks (16,896 addresses) and 0 IPv6 networks, mostly in Netherlands. Prefix list for firewalls.

AS13205
Organisation
British Telecommunications PLC
Countries (share of addresses)
Netherlands 51.5% United Kingdom 48.5%
IPv4 addresses
16,896
IPv4 networks
4
IPv6 networks
0

IPv4 networks 4

IPv6 networks 0

No networks.

Prefix list for a firewall

Ready-made rules to allow or block the whole of AS13205.

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.