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AS3300British Telecommunications Limited

United KingdomRegistryRIPE NCC

As of 27th September 2026, AS3300 (British Telecommunications Limited), a network registered in the United Kingdom with RIPE NCC, originates 123 IPv4 prefixes covering 604k addresses and 29 IPv6 prefixes. By IPv4 address space that makes it the 631st-largest of the 79,525 networks we see originating IPv4, and the 16th-largest of 2,074 in the United Kingdom. It is seen behind 39 upstream networks, most often AS2914 (NTT America, Inc.) and AS1299 (Arelion (fka. Telia Carrier)), and in front of 20 downstream networks. 71% of its announcements have a valid RPKI ROA, and none are RPKI-invalid. 100% of its routes reach at least 90% of full-feed peers.

At a glance

IPv4 prefixes

123

IPv6 prefixes

29

IPv4 addresses

604k

IPv6 /64s

12.8B

Upstream graph

The networks AS3300 is seen behind, one and two hops out, drawn from real AS paths.

AS3300Toward the internet core
Upstream graph for AS3300: 12 neighbouring networks observed beyond it across 2 levels. The same networks are listed in the tables below.AS3300British Telecommu…This networkAS1299Arelion (fka. Tel…AS2914NTT America, Inc.AS3491PCCW Global (HK) …AS4637Telstra Internati…AS4657StarHub LtdAS8888xTom Pty LtdAS13030Init7 (Switzerlan…AS3130RGnet OUAS49544i3D.net B.VAS24516Virtutel Pty LtdAS16552Tiggee LLCAS32590Valve Corporation

Networks observed one and two hops upstream of AS3300 in real AS paths. A thicker line means more vantage points saw that adjacency, so weight tracks how well attested it is — not how much traffic it carries. Adjacency is an observation; whether it is a transit purchase or a settlement-free peering is an inference, and is labelled as one wherever we show it.

Neighbouring networks

185

adjacent networks

Upstreams
3921%
Peers
12668%
Downstreams
2011%

Networks carrying this one's traffic toward the rest of the internet.

Upstreams of AS3300
NetworkCountryRelationshipPathsVantage pts
AS2914NTT America, Inc.USPeer3,834109
AS1299Arelion (fka. Telia Carrier)SEPeer3,571116
AS4637Telstra International LimitedHKPeer1,846112
AS3491PCCW Global (HK) Ltd.HKPeer1,06177
AS4657StarHub LtdSGPeer70858
AS6939Hurricane Electric LLCUSPeer63020
AS2497Internet Initiative Japan Inc.JPPeer5615
AS9002RETN LimitedGBPeer51614
AS6762Telecom Italia Sparkle (Seabone)ITPeer40686
AS18106Viewqwest Pte LtdSGPeer3853

Prefixes

All 152

The largest blocks AS3300 originates, widest first.

Largest prefixes originated by AS3300
PrefixAddressesVisibility
205.248.0.0/1665.5k81/81
206.182.0.0/1665.5k81/81
207.117.0.0/1665.5k81/81
207.209.0.0/1665.5k81/81
209.28.0.0/1665.5k81/81
204.231.0.0/1732.8k81/81
61.14.0.0/1816.4k81/81
63.250.128.0/1816.4k81/81
192.237.64.0/1816.4k81/81
198.207.64.0/1816.4k81/81

Routing health

How AS3300's own announcements validate against RPKI and how far they propagate. The same measures for the whole routing table are on the routing table in numbers.

RPKI origin validation

  • Valid71.1%108
  • Invalid0.0%0
  • No ROA28.9%44

Propagation

  • Globally propagated90% of full-feed peers or more100.0%152
  • Partially propagated40% to 90%0.0%0
  • Seen by few peersUnder 40%0.0%0

Prefix sizes

IPv4 — 123 prefixes

IPv6 — 29 prefixes

  • /324.3B × /646.9%2
  • /36268M × /6451.7%15
  • /4016.8M × /6441.4%12

Recent changes

Announcements that started or stopped since 28th Aug 2026.

No announcement by AS3300 started or stopped in this period.

Routing data derived from RouteViews MRT archives, BGPKIT relationship inference and public registry data.