Country
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ASN LANDING PAGE
AS5400
BT British Telecommunications PLC
Last updated · Apr 10, 2026
Total prefixes
109
IPv4 prefixes
77
IPv6 prefixes
32
ASN summary
How to read the scale of AS5400
BT British Telecommunications PLC currently shows 109 prefixes and 80 upstream, downstream, or peer relationships. Larger prefix inventories often indicate broader network footprint, but they should still be read together with country and peering context.
When is an ASN page most useful?
ASN landing pages are more useful than a single IP page when you want cloud provider attribution, routing research, infrastructure comparison, or network topology analysis at the organization level.
How should you read the country, organization, and role of AS5400?
BT British Telecommunications PLC is currently associated with an unknown region. Country data is only a starting point; the more important signals are the organization name, website, prefix volume, and peering relationships that reveal whether the network behaves like a cloud platform, ISP, CDN, or enterprise backbone.
What should you inspect next after the AS5400 page?
This page is currently showing live ASN data that can be used for peer, prefix, and network scale analysis. The most useful next step is usually to return to a related IP landing page, then compare that concrete address with this ASN profile and with broader topic pages for routing, cloud attribution, or WHOIS ownership analysis.
Search intents this ASN page helps cover
AS5400 ASN lookupAS5400 BGPAS5400 peersAS5400 prefixesAS5400 upstreamsBT British Telecommunications PLC ASN
Upstreams
Detailed data for this ASN is not available right now.
Downstreams
AS2856
AS2856
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AS2110
AS2110
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AS199541
AS199541
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AS25049
AS25049
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AS8968
AS8968
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AS29063
AS29063
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AS42848
AS42848
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AS7246
AS7246
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AS40126
AS40126
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AS21489
AS21489
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AS59724
AS59724
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AS51046
AS51046
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AS22683
AS22683
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AS3573
AS3573
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AS13205
AS13205
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AS12298
AS12298
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AS203990
AS203990
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AS21000
AS21000
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AS34311
AS34311
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AS31614
AS31614
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AS30864
AS30864
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AS202666
AS202666
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AS208053
AS208053
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AS27311
AS27311
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AS48647
AS48647
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AS207180
AS207180
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AS8903
AS8903
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AS51466
AS51466
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AS206625
AS206625
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AS212565
AS212565
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AS7734
AS7734
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AS394805
AS394805
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AS72
AS72
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AS12734
AS12734
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AS10780
AS10780
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AS15518
AS15518
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AS202097
AS202097
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AS15442
AS15442
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AS51527
AS51527
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AS13130
AS13130
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Peers
AS1299
AS1299
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AS3356
AS3356
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AS174
AS174
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AS6939
AS6939
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AS6762
AS6762
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AS3257
AS3257
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AS3491
AS3491
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AS6453
AS6453
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AS9002
AS9002
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AS8283
AS8283
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AS3320
AS3320
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AS12956
AS12956
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AS30781
AS30781
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AS5511
AS5511
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AS13030
AS13030
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AS2856
AS2856
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AS39351
AS39351
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AS35280
AS35280
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AS8218
AS8218
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AS24961
AS24961
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AS6830
AS6830
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AS37468
AS37468
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AS2497
AS2497
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AS20485
AS20485
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AS4637
AS4637
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AS50304
AS50304
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AS199524
AS199524
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AS6881
AS6881
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AS1836
AS1836
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AS19151
AS19151
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AS31027
AS31027
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AS14907
AS14907
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AS33891
AS33891
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AS577
AS577
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AS52320
AS52320
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AS45489
AS45489
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AS6730
AS6730
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AS1257
AS1257
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AS680
AS680
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AS1853
AS1853
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Prefix inventory
| Prefix | Name | Country |
|---|---|---|
| 132.244.240.0/24 | AS5400 | — |
| 132.244.64.0/21 | AS5400 | — |
| 132.244.72.0/21 | AS5400 | — |
| 136.238.224.0/24 | AS5400 | — |
| 136.238.84.0/24 | AS5400 | — |
| 136.238.85.0/24 | AS5400 | — |
| 166.49.128.0/17 | AS5400 | — |
| 185.249.4.0/24 | AS5400 | — |
| 185.94.0.0/22 | AS5400 | — |
| 192.109.52.0/24 | AS5400 | — |
| 193.202.26.0/24 | AS5400 | — |
| 193.58.130.0/23 | AS5400 | — |
| 194.107.114.0/24 | AS5400 | — |
| 194.213.64.0/19 | AS5400 | — |
| 194.33.53.0/24 | AS5400 | — |
| 194.33.54.0/24 | AS5400 | — |
| 194.33.55.0/24 | AS5400 | — |
| 194.50.160.0/24 | AS5400 | — |
| 194.74.80.0/21 | AS5400 | — |
| 194.76.40.0/24 | AS5400 | — |
| 195.100.0.0/16 | AS5400 | — |
| 195.163.0.0/16 | AS5400 | — |
| 195.171.36.0/22 | AS5400 | — |
| 195.182.96.0/19 | AS5400 | — |
| 195.36.82.0/24 | AS5400 | — |
| 195.60.182.0/24 | AS5400 | — |
| 195.60.183.0/24 | AS5400 | — |
| 195.66.70.0/24 | AS5400 | — |
| 195.90.64.0/19 | AS5400 | — |
| 195.99.64.0/20 | AS5400 | — |
| 198.178.236.0/24 | AS5400 | — |
| 2001:740::/32 | AS5400 | — |
| 203.158.68.0/23 | AS5400 | — |
| 203.158.72.0/23 | AS5400 | — |
| 203.158.76.0/23 | AS5400 | — |
| 204.52.188.0/24 | AS5400 | — |
| 206.73.0.0/16 | AS5400 | — |
| 206.73.0.0/19 | AS5400 | — |
| 206.73.112.0/22 | AS5400 | — |
| 206.73.116.0/22 | AS5400 | — |
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Related lookups and next steps
WHOIS vs ASN Ownership Guide
Continue from this ASN into the differences between WHOIS ownership and ASN ownership.
Routing Troubleshooting and Network Analysis
Continue from this ASN into route troubleshooting and network analysis.
Cloud Network and ASN Comparison
Useful when you want to compare this ASN against larger cloud and edge networks.
WHOIS and IP Ownership Guide
Continue from the ASN page into WHOIS and ownership verification.
Frequently asked questions about this ASN page
What does AS5400 represent?
AS5400 is an autonomous system number used to identify an independently operated network. The current page associates it with BT British Telecommunications PLC in an unknown region, which helps determine whether it behaves like a cloud provider, ISP, CDN, or enterprise backbone.
What are peers, upstreams, and prefixes useful for on the AS5400 page?
They help explain the scale, interconnection depth, and route structure of AS5400. Richer peering and upstream data often indicate broader network reach, but they should still be interpreted together with prefixes and related IP landing pages.
What should you do after reviewing AS5400?
The best next step is usually to return to a concrete IP landing page to see how a specific address maps into AS5400, then continue into cloud, WHOIS, or routing topic pages to understand the network in a broader context.
Related topics
WHOIS vs ASN Ownership Guide
Understand why WHOIS ownership and ASN ownership can differ, and how to combine both when deciding who really owns or operates an IP.
WHOIS and IP Ownership Guide
Use WHOIS, ASN, prefixes, and organization data to determine who ultimately owns an IP, range, or resolved domain target.
BGP and ASN Basics Guide
Learn what ASN, BGP routes, prefixes, upstreams, downstreams, and peers mean, then explore real ASN pages.
Cloud Network and ASN Comparison
Compare large cloud and edge networks such as Google, Cloudflare, Microsoft, and Amazon through their ASN landing pages.