$ query “AS15412” --type=asn → 1 result(s)

AS15412 · FLAG-AS

Flag Telecom UK Limited

AS15412 is operated by Flag Telecom UK Limited and serves as a mid-size transit provider, based in the United Kingdom since 2002. The system announces a respectable 34 048 IPv4 addresses, and supports IPv6. The bulk of its IP address space is in the United Kingdom, with additional presence in Hong Kong SAR China and Spain, and smaller footprints in 14 additional countries.

  • Top 5% — Top 5% of all autonomous systems by reach and degree
  • #35 by Reach — Top 100 by customer cone size
  • #4 in United Kingdom — Top 10 by reach within country

Basic Information

Country
🇬🇧 United Kingdom
Category
Internet Service Provider
Network Role
Mid-size Transit
Data Origin
Authoritative — Metadata from authoritative RIR registry (ARIN, RIPE, APNIC, etc.)
Registered
September 18, 2002
Last Changed
April 30, 2026
Last Seen
May 18, 2026 (active)

Prefix Summary

IPv4 Prefixes (raw / aggregated)
21 / 15
IPv6 Prefixes (raw / aggregated)
1 / 1
IPv4 Addresses
34 048
Largest IPv4 Prefix
/19 (8 192 addresses)
Largest IPv6 Prefix
/32
Geolocated Countries
🇬🇧 United Kingdom (26 720 IPs), 🇭🇰 Hong Kong SAR China (9 008 IPs), 🇪🇸 Spain (8 192 IPs) and 14 more
Prefix Changed
April 03, 2026

Reputation

Reputation
Pristine — 0 flagged IPs

Connectivity Summary

Upstream Providers
5 upstreams providing transit
Peers
340 networks exchanging traffic without transit
Downstream Customers
42 downstreams buying transit
Unclassified
2 unclassified BGP neighbors
Degree
389 unique BGP neighbors
Reach
49 494 networks in customer cone

Upstream Providers (5)

  • AS6939 — HURRICANE
  • AS174 — COGENT (Tier-1 transit)
  • AS1299 — TWELVE99 (Tier-1 transit)
  • AS2914 — NTT-DATA-2914 (Tier-1 transit)
  • AS6762 — SEABONE-NET (Tier-1 transit)

Prefix Lists

IPv4 Prefixes (21 total)

  • 80.81.64.0/19 (8 192 addresses (/19 prefix))
  • 62.216.128.0/19 (8 192 addresses (/19 prefix))
  • 203.79.32.0/20 (4 096 addresses (/20 prefix))
  • 80.77.0.0/20 (4 096 addresses (/20 prefix))
  • 103.5.160.0/22 (1 024 addresses (/22 prefix))
  • 85.95.24.0/22 (1 024 addresses (/22 prefix))
  • 43.248.216.0/22 (1 024 addresses (/22 prefix))
  • 103.8.84.0/22 (1 024 addresses (/22 prefix))
  • 103.15.116.0/22 (1 024 addresses (/22 prefix))
  • 103.103.152.0/22 (1 024 addresses (/22 prefix))
  • 103.225.192.0/22 (1 024 addresses (/22 prefix))
  • 45.125.188.0/22 (1 024 addresses (/22 prefix))
  • 103.144.202.0/23 (512 addresses (/23 prefix))
  • 103.154.20.0/23 (512 addresses (/23 prefix))
  • 103.11.237.0/24 (256 addresses (/24 prefix))

IPv6 Prefixes (1 total)

  • 2001:1a00::/32