prefixkit Ask an engineerAsk RU

Autonomous systems

AS3300 British Telecommunications PLC

Autonomous system AS3300 (British Telecommunications PLC): 50 IPv4 networks (513,024 addresses) and 34 IPv6 networks, mostly in United States. Prefix list for firewalls.

AS3300
Organisation
British Telecommunications PLC
Countries (share of addresses)
United States 53% Canada 18.5% Singapore 4.3% Japan 3.5% Hong Kong SAR China 2.4% Germany 2.2% Netherlands 1.3% Brazil 1.2%
IPv4 addresses
513,024
IPv4 networks
50
IPv6 networks
34

IPv4 networks 50

Show 2 more

IPv6 networks 34

Prefix list for a firewall

Ready-made rules to allow or block the whole of AS3300.

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.