$ query “AS5400” --type=asn → 1 result(s)

AS5400 · BT

British Telecommunications PLC

AS5400 is operated by British Telecommunications PLC and serves as a major transit provider, established in the United Kingdom in 2002. The system announces a solid 703 232 IPv4 addresses, including a /16, and supports IPv6. The bulk of its IP address space is in Sweden, with additional presence in the United Kingdom and Germany, and smaller footprints in 44 additional countries. This AS's prefix announcements have been recently modified.

  • Top 5% — Top 5% of all autonomous systems by reach and degree

Basic Information

Country
🇬🇧 United Kingdom
Category
Internet Service Provider
Network Role
Major Transit
Data Origin
Authoritative — Metadata from authoritative RIR registry (ARIN, RIPE, APNIC, etc.)
Registered
August 29, 2002
Last Changed
March 04, 2026
Last Seen
April 29, 2026 (active)

Prefix Summary

IPv4 Prefixes (raw / aggregated)
74 / 60
IPv6 Prefixes (raw / aggregated)
27 / 11
IPv4 Addresses
703 232
Largest IPv4 Prefix
/16 (65 536 addresses)
Largest IPv6 Prefix
/23
Geolocated Countries
🇸🇪 Sweden (477 040 IPs), 🇬🇧 United Kingdom (227 712 IPs), 🇩🇪 Germany (152 848 IPs) and 44 more
Prefix Changed
April 24, 2026

Reputation

Reputation
Pristine — 0 flagged IPs

Connectivity Summary

Upstream Providers
4 upstreams providing transit
Peers
93 networks exchanging traffic without transit
Downstream Customers
64 downstreams buying transit
Unclassified
2 unclassified BGP neighbors
Degree
163 unique BGP neighbors
Reach
322 networks in customer cone

Upstream Providers (4)

  • AS3356 — LEVEL3 (Tier-1 transit)
  • AS1299 — TWELVE99 (Tier-1 transit)
  • AS3549 — LVLT-3549
  • AS4637 — ASN-TELSTRA-GLOBAL

Prefix Lists

IPv4 Prefixes (74 total)

  • 62.134.0.0/16 (65 536 addresses (/16 prefix))
  • 195.163.0.0/16 (65 536 addresses (/16 prefix))
  • 206.73.0.0/16 (65 536 addresses (/16 prefix))
  • 213.15.0.0/16 (65 536 addresses (/16 prefix))
  • 195.100.0.0/16 (65 536 addresses (/16 prefix))
  • 62.180.0.0/16 (65 536 addresses (/16 prefix))
  • 166.49.128.0/17 (32 768 addresses (/17 prefix))
  • 62.5.0.0/17 (32 768 addresses (/17 prefix))
  • 62.102.0.0/17 (32 768 addresses (/17 prefix))
  • 212.162.192.0/18 (16 384 addresses (/18 prefix))
  • 213.236.64.0/18 (16 384 addresses (/18 prefix))
  • 213.194.0.0/18 (16 384 addresses (/18 prefix))
  • 62.173.192.0/18 (16 384 addresses (/18 prefix))
  • 213.137.160.0/19 (8 192 addresses (/19 prefix))
  • 194.213.64.0/19 (8 192 addresses (/19 prefix))
  • 82.150.0.0/19 (8 192 addresses (/19 prefix))
  • 195.90.64.0/19 (8 192 addresses (/19 prefix))
  • 195.182.96.0/19 (8 192 addresses (/19 prefix))
  • 82.138.160.0/19 (8 192 addresses (/19 prefix))
  • 212.8.160.0/19 (8 192 addresses (/19 prefix))
  • 212.21.192.0/19 (8 192 addresses (/19 prefix))
  • 212.31.192.0/19 (8 192 addresses (/19 prefix))
  • 31.95.96.0/19 (8 192 addresses (/19 prefix))
  • 212.127.0.0/19 (8 192 addresses (/19 prefix))
  • 212.108.0.0/19 (8 192 addresses (/19 prefix))
  • 212.41.128.0/19 (8 192 addresses (/19 prefix))
  • 31.95.160.0/20 (4 096 addresses (/20 prefix))
  • 80.255.160.0/20 (4 096 addresses (/20 prefix))
  • 31.95.16.0/20 (4 096 addresses (/20 prefix))
  • 132.244.64.0/20 (4 096 addresses (/20 prefix))
  • 195.99.64.0/20 (4 096 addresses (/20 prefix))
  • 194.74.80.0/21 (2 048 addresses (/21 prefix))
  • 31.95.48.0/21 (2 048 addresses (/21 prefix))
  • 31.95.0.0/21 (2 048 addresses (/21 prefix))
  • 62.172.0.0/21 (2 048 addresses (/21 prefix))
  • 185.94.0.0/22 (1 024 addresses (/22 prefix))
  • 46.248.8.0/22 (1 024 addresses (/22 prefix))
  • 195.171.36.0/22 (1 024 addresses (/22 prefix))
  • 203.158.76.0/23 (512 addresses (/23 prefix))
  • 194.33.54.0/23 (512 addresses (/23 prefix))
  • 195.60.182.0/23 (512 addresses (/23 prefix))
  • 217.180.16.0/23 (512 addresses (/23 prefix))
  • 31.95.218.0/23 (512 addresses (/23 prefix))
  • 203.158.68.0/23 (512 addresses (/23 prefix))
  • 203.158.72.0/23 (512 addresses (/23 prefix))
  • 136.238.84.0/23 (512 addresses (/23 prefix))
  • 193.58.130.0/23 (512 addresses (/23 prefix))
  • 194.76.40.0/24 (256 addresses (/24 prefix))
  • 194.50.160.0/24 (256 addresses (/24 prefix))
  • 195.66.70.0/24 (256 addresses (/24 prefix))
  • and 10 more

IPv6 Prefixes (27 total)

  • 2a00:2000::/23
  • 2a00:2200::/24
  • 2a00:2300::/25
  • 2a0c:7c80::/29
  • 2001:740::/32
  • 2606:f100:d800::/37
  • 2606:f100:d400::/38
  • 2402:fb00:8000::/39
  • 2402:fb00:8400::/39
  • 2606:f100:d000::/39
  • 2402:fb00:8800::/40