1. All IP Ranges
  2. 81.0.0.0/8
  3. AS2856  | 81.128.0.0/12

81.128.0.0/12

AS2856  ·  British Telecommunications PLC

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Summary

Country United Kingdom
Domain bt.com
ASN AS2856
Parent Range 81.128.0.0/11
Registry RIPE
ID BT-INFRA

WHOIS Details

inetnum:        81.128.0.0 - 81.143.255.255
netname:        BT-INFRA
descr:          BT Infrastructure Layer
country:        GB
admin-c:        BS1474-RIPE
tech-c:         BS1474-RIPE
status:         LIR-PARTITIONED PA
mnt-by:         BTNET-INFRA-MNT
mnt-lower:      BTNET-MNT
mnt-routes:     BTNET-MNT
created:        2014-08-01T07:43:40Z
last-modified:  2014-08-01T07:43:40Z
source:         RIPE
abuse-email:    abuse@bt.com
abuse-c:        AR13878-RIPE
abuse-org:      ORG-BPIS1-RIPE

role:           BTnet Support
address:        Adhara
address:        Adastral Park
address:        Martlesham Heath
address:        Ipswich
address:        SUFFLK IP5 3RE
address:        GB
phone:          +44 800 0858963 5
phone:          +44 1473 336231
e-mail:         as2856peering@bt.com
e-mail:         btnetdns@bt.com
admin-c:        FLS15-RIPE
tech-c:         FLS15-RIPE
nic-hdl:        BS1474-RIPE
remarks:        For all queries contact as2856peering@bt.com
remarks:        Please send delisting issues to btnetdns@bt.com
mnt-by:         BTNET-MNT
created:        2002-04-30T07:54:10Z
last-modified:  2025-07-18T13:07:21Z
source:         RIPE

route:          81.128.0.0/12
descr:          BT Public Internet Service
origin:         AS2856
mnt-by:         BTNET-INFRA-MNT
notify:         ip.address.admin@bt.com
created:        2005-06-16T14:11:53Z
last-modified:  2014-07-31T07:47:16Z
source:         RIPE

Overlapping Ranges

BGP prefixes that contain 81.128.0.0/12

Range ASN Company Num of IPs
81.128.0.0/11 AS2856 British Telecommunications PLC 2,097,152

Nearby Ranges

BGP prefixes that overlap with 81.0.0.0/8

Range ASN Company Num of IPs
81.128.0.0/11 AS2856 British Telecommunications PLC 2,097,152
81.96.0.0/12 AS5089 Virgin Media Limited 1,048,576
81.212.0.0/14 AS9121 Turk Telekomunikasyon Anonim Sirketi 262,144
81.76.0.0/14 AS5378 Vodafone Limited 262,144
81.64.0.0/14 AS15557 Societe Francaise Du Radiotelephone - SFR SA 262,144
81.204.0.0/14 AS1136 KPN B.V. 262,144
81.68.0.0/14 AS45090 Tencent Cloud Computing (Beijing) Co., Ltd 262,144
81.178.0.0/15 AS13285 TalkTalk Communications Limited 131,072
81.60.0.0/15 AS12430 VODAFONE ONO, S.A. 131,072
81.56.0.0/15 AS29447 Free SAS 131,072
81.82.0.0/15 AS6848 Telenet BV 131,072
81.164.0.0/15 AS6848 Telenet BV 131,072
81.62.0.0/15 AS3303 Swisscom (Schweiz) AG 131,072
81.182.0.0/15 AS5483 Magyar Telekom Plc. 131,072
81.166.0.0/15 AS29695 Lyse Tele AS 131,072
81.192.0.0/16 AS6713 Office National des Postes et Telecommunications ONPT (Maroc Telecom) / IAM 65,536
81.198.0.0/16 AS24921 SIA Tet 65,536
81.193.0.0/16 AS3243 MEO - SERVICOS DE COMUNICACOES E MULTIMEDIA S.A. 65,536
81.185.0.0/16 AS15557 Societe Francaise Du Radiotelephone - SFR SA 65,536
81.195.0.0/16 AS8359 MTS PJSC 65,536
81.32.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.44.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.87.0.0/16 AS786 Jisc Services Limited 65,536
81.36.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.38.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.202.0.0/16 AS6739 Cableuropa - ONO 65,536
81.190.0.0/16 AS21021 Multimedia Polska Sp. z o.o. 65,536
81.34.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.37.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.61.0.0/16 AS6739 ONO_HFC 65,536
81.40.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.35.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.39.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.220.0.0/16 AS15557 Societe Francaise Du Radiotelephone - SFR SA 65,536
81.187.0.0/16 AS20712 Andrews & Arnold Ltd 65,536
81.184.0.0/16 AS6739 VODAFONE ONO, S.A. 65,536
81.33.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.80.0.0/16 AS3215 Orange S.A. 65,536
81.188.0.0/16 AS3257 GTT Communications Belgium N.V. 65,536
81.126.0.0/16 AS3269 Telecom Italia S.p.A. 65,536
81.196.0.0/16 AS8708 DIGI ROMANIA S.A. 65,536
81.219.0.0/16 AS12741 Netia SA 65,536
81.189.0.0/16 AS8437 Network of Hutchison Drei Austria GmbH 65,536
81.57.0.0/16 AS29447 Iliad / Free SAS 65,536
81.218.0.0/16 AS8551 Bezeq International Ltd. 65,536
81.197.0.0/16 AS719 Elisa Oyj 65,536
81.198.0.0/16 AS12578 SIA Tet 65,536
81.191.0.0/16 AS2116 GLOBALCONNECT AS 65,536
81.81.0.0/16 AS1267 WIND TRE S.P.A. 65,536

Hosted domains

There are 3,664 domain names hosted across 1,652 IP addresses on this ASN. Checkout our API to access full domain hosting information.

IP Address Domain Domains on this IP
81.134.40.54 totalclimatecontrolltd.co.uk 108
81.142.113.81 mobilityleicester.uk 88
81.128.239.117 drinks-live.com 60
81.128.160.145 falconryonline.com 60
81.133.252.110 airhandlingsystems.co.uk 41
81.130.171.229 openstack.host 30
81.133.74.88 cornerstone.systems 30
81.139.48.154 isis-icon.co.uk 25
81.133.56.18 sserfiles.com 24
81.143.201.172 gs-systems.co.uk 23
81.142.49.6 blu-raymultiregion.com 21
81.137.54.177 reliancemarine.co.uk 16
81.130.165.202 shoeshed.co.uk 15
81.134.37.149 boggerchops.co.uk 14
81.130.179.42 alexsanders.uk 14
81.128.245.171 turnerlittle.es 14
81.143.29.9 upsmonitor.net 13
81.136.244.112 admit-one-test.eu 12
81.137.202.197 chesterarchitect.com 12
81.128.203.38 clogau.biz 11

Hosted domains API

Our Hosted Domains API, or Reverse IP API returns a full list of domains that are hosted on a single IP address.
Useful for Cybersecurity
Read more

Pingable IPs

373,335 IPs in this range replied to an ICMP ping during our most recent internet scan. Learn more.

IP Address ASN Details
81.139.132.181 AS2856 British Telecommunications PLC 3.25ms from London, GB
81.139.163.187 AS2856 British Telecommunications PLC 5.67ms from London, GB
81.139.215.184 AS2856 British Telecommunications PLC 5.48ms from London, GB
81.139.141.110 AS2856 British Telecommunications PLC 3.99ms from London, GB
81.138.100.121 AS2856 British Telecommunications PLC 7.22ms from London, GB
81.139.168.12 AS2856 British Telecommunications PLC 4.88ms from London, GB
81.139.148.36 AS2856 British Telecommunications PLC 12.01ms from Erith, GB
81.139.216.130 AS2856 British Telecommunications PLC 3.16ms from Erith, GB
81.138.157.25 AS2856 British Telecommunications PLC 3.54ms from London, GB
81.138.75.78 AS2856 British Telecommunications PLC 5.13ms from London, GB
81.138.77.177 AS2856 British Telecommunications PLC 5.61ms from London, GB
81.138.64.217 AS2856 British Telecommunications PLC 10.37ms from London, GB
81.138.152.134 AS2856 British Telecommunications PLC 8.06ms from Erith, GB
81.138.237.230 AS2856 British Telecommunications PLC 50.76ms from London, GB
81.139.218.2 AS2856 British Telecommunications PLC 4.58ms from London, GB
81.138.220.206 AS2856 British Telecommunications PLC 4.96ms from London, GB
81.139.128.1 AS2856 British Telecommunications PLC 0.66ms from London, GB
81.139.41.210 AS2856 British Telecommunications PLC 1.18ms from London, GB
81.139.142.249 AS2856 British Telecommunications PLC 6.90ms from London, GB
81.138.164.238 AS2856 British Telecommunications PLC 17.37ms from London, GB
81.138.89.129 AS2856 British Telecommunications PLC 6.07ms from Erith, GB
81.138.86.238 AS2856 British Telecommunications PLC 8.52ms from London, GB
81.138.150.137 AS2856 British Telecommunications PLC 25.50ms from London, GB
81.139.164.64 AS2856 British Telecommunications PLC 5.48ms from London, GB
81.139.145.40 AS2856 British Telecommunications PLC 5.87ms from London, GB

Other Pingable IPs

Below is a random selection of 25 IPs that replied to an ICMP ping during our most recent internet scan.

IP Address ASN Details
23.109.53.156 AS7979 Servers.com, Inc. 0.15ms from Amsterdam, NL
73.215.180.28 AS7922 Comcast Cable Communications, LLC 8.76ms from Ashburn, US
40.121.252.108 AS8075 Microsoft Corporation 0.49ms from Ashburn, US
79.221.115.156 AS3320 Deutsche Telekom AG 2.33ms from Berlin, DE
20.69.221.236 AS8075 Microsoft Corporation 0.29ms from Boydton, US
134.3.37.92 AS3209 Vodafone GmbH 11.43ms from Frankfurt am Main, DE
114.130.42.60 AS139616 The Central Bank of Bangladesh 9.97ms from Kolkata, IN
40.104.112.60 AS8075 Microsoft Corporation 0.25ms from London, GB
213.176.45.252 AS142578 E-Large (HongKong) 0.22ms from Los Angeles, US
210.175.152.44 AS7687 TOYOTA SYSTEMS CORPORATION 4.95ms from Osaka, JP
88.182.119.92 AS12322 Free SAS 3.68ms from Paris, FR
119.176.78.108 AS4837 CHINA UNICOM China169 Backbone 3.33ms from Qingdao, CN
54.211.59.252 AS14618 Amazon.com, Inc. 0.21ms from Reston, US
71.231.7.172 AS7922 Comcast Cable Communications, LLC 3.52ms from Seattle, US
110.93.173.220 AS38690 HyosungITX 1.13ms from Seoul, KR
190.97.97.252 AS26317 Lisa Communications Ltd 12.80ms from Willemstad, CW
185.45.113.108 AS29141 Bradler & Krantz GmbH & Co. KG 0.82ms from Amsterdam, NL
96.16.241.108 AS16625 Akamai Technologies, Inc. 0.22ms from Dallas, US
99.156.176.60 AS7018 AT&T Enterprises, LLC 4.02ms from Dallas, US
92.216.52.156 AS3209 Vodafone GmbH 6.13ms from Frankfurt am Main, DE
175.6.223.12 AS4134 CHINANET-BACKBONE 15.43ms from Guangzhou, CN
36.26.75.204 AS58461 CT-HangZhou-IDC 5.51ms from Hangzhou, CN
8.223.42.108 AS45102 Alibaba (US) Technology Co., Ltd. 1.01ms from Hong Kong, HK
74.41.8.108 AS5650 Frontier Communications of America, Inc. 14.72ms from Los Angeles, US
69.123.94.220 AS6128 Cablevision Systems Corp. 7.57ms from New York City, US

Traceroute

Below is a recent traceroute taken from the IPinfo ProbeNet to an IP in this range. Learn more.

$
traceroute -a -n -q1 -f4 81.141.37.156
traceroute to 81.141.37.156 (81.141.37.156): 64 hops max, 52 byte packets
5 [AS2856] 194.74.16.154 5.299 ms
6 *
7 *
8 [AS2856] 81.141.37.156 10.945 ms
Measurement taken from IPinfo ProbeNet in Coventry, GB
On

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Traffic works its way around the internet based on the routing table, which contains a list of networks and their associated netblocks.

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