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
81.204.0.0/14 AS1136 KPN B.V. 262,144
81.68.0.0/14 AS45090 Tencent Cloud Computing (Beijing) Co., Ltd 262,144
81.64.0.0/14 AS15557 Societe Francaise Du Radiotelephone - SFR SA 262,144
81.76.0.0/14 AS5378 Vodafone Limited 262,144
81.62.0.0/15 AS3303 Swisscom (Schweiz) AG 131,072
81.60.0.0/15 AS12430 VODAFONE ONO, S.A. 131,072
81.82.0.0/15 AS6848 Telenet BV 131,072
81.182.0.0/15 AS5483 Magyar Telekom Plc. 131,072
81.178.0.0/15 AS13285 TalkTalk Communications Limited 131,072
81.56.0.0/15 AS29447 Free SAS 131,072
81.164.0.0/15 AS6848 Telenet BV 131,072
81.166.0.0/15 AS29695 Lyse Tele AS 131,072
81.34.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.44.0.0/16 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
81.56.0.0/16 AS29447 Iliad / Free SAS 65,536
81.187.0.0/16 AS41489 Andrews & Arnold Ltd 65,536
81.32.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.189.0.0/16 AS8437 Network of Hutchison Drei Austria GmbH 65,536
81.223.0.0/16 AS8412 T-Mobile Austria GmbH 65,536
81.196.0.0/16 AS8708 DIGI ROMANIA S.A. 65,536
81.219.0.0/16 AS12741 Netia SA 65,536
81.40.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.36.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.84.0.0/16 AS2860 NOS COMUNICACOES, S.A. 65,536
81.191.0.0/16 AS2116 GLOBALCONNECT AS 65,536
81.194.0.0/16 AS2200 Renater 65,536
81.198.0.0/16 AS12578 SIA Tet 65,536
81.33.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.126.0.0/16 AS3269 Telecom Italia S.p.A. 65,536
81.80.0.0/16 AS3215 Orange S.A. 65,536
81.193.0.0/16 AS3243 MEO - SERVICOS DE COMUNICACOES E MULTIMEDIA S.A. 65,536
81.86.0.0/16 AS13285 TalkTalk Communications Limited 65,536
81.57.0.0/16 AS29447 Iliad / Free SAS 65,536
81.216.0.0/16 AS1257 Tele2 Sverige AB 65,536
81.188.0.0/16 AS3257 GTT Communications Belgium N.V. 65,536
81.81.0.0/16 AS1267 WIND TRE S.P.A. 65,536
81.37.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.38.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.187.0.0/16 AS20712 Andrews & Arnold Ltd 65,536
81.198.0.0/16 AS24921 SIA Tet 65,536
81.87.0.0/16 AS786 Jisc Services Limited 65,536
81.202.0.0/16 AS6739 Cableuropa - ONO 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

Hosted domains

There are 3,647 domain names hosted across 1,645 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 smellaway.co.uk 106
81.128.160.145 kangarooleather.co.uk 60
81.128.239.117 worldsherryawards.com 60
81.136.181.36 sapweb.services 59
81.133.252.110 iaq-filtration.com 41
81.130.171.229 hartwell.tech 30
81.133.74.88 rlpower.co.uk 30
81.143.201.172 tillrolls-shop.eu 23
81.142.49.6 blu-raymultiregion.com 21
81.133.228.187 pitt-stop.cymru 19
81.128.160.188 priceengines.com 19
81.128.195.220 obis-uk.co.uk 16
81.130.165.202 faulknersfootwear.co.uk 15
81.128.245.172 renrutconsultancy.co.uk 15
81.128.245.171 turnerlittle.co 14
81.134.37.149 cloudfibre.net 14
81.130.208.151 xnovarevolution.com 13
81.136.244.112 admit-one-email.com 12
81.133.105.103 woooba.io 10
81.133.80.166 pisang.uk 10

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

408,871 IPs in this range replied to an ICMP ping during our most recent internet scan. Learn more.

IP Address ASN Details
81.143.224.241 AS2856 British Telecommunications PLC 1.97ms from Erith, GB
81.143.126.230 AS2856 British Telecommunications PLC 13.40ms from London, GB
81.143.207.129 AS2856 British Telecommunications PLC 2.65ms from London, GB
81.143.253.236 AS2856 British Telecommunications PLC 5.54ms from London, GB
81.143.108.166 AS2856 British Telecommunications PLC 6.79ms from Erith, GB
81.143.182.95 AS2856 British Telecommunications PLC 2.90ms from London, GB
81.143.203.23 AS2856 British Telecommunications PLC 2.10ms from London, GB
81.143.218.99 AS2856 British Telecommunications PLC 2.64ms from London, GB
81.143.158.102 AS2856 British Telecommunications PLC 16.21ms from London, GB
81.143.62.254 AS2856 British Telecommunications PLC 5.59ms from London, GB
81.143.177.6 AS2856 British Telecommunications PLC 4.91ms from London, GB
81.143.250.121 AS2856 British Telecommunications PLC 5.43ms from London, GB
81.143.236.85 AS2856 British Telecommunications PLC 2.35ms from Erith, GB
81.143.233.66 AS2856 British Telecommunications PLC 1.36ms from Erith, GB
81.143.69.246 AS2856 British Telecommunications PLC 5.76ms from London, GB
81.143.109.142 AS2856 British Telecommunications PLC 12.79ms from London, GB
81.143.185.99 AS2856 British Telecommunications PLC 3.37ms from London, GB
81.143.226.121 AS2856 British Telecommunications PLC 3.07ms from London, GB
81.143.235.107 AS2856 British Telecommunications PLC 2.46ms from London, GB
81.143.160.18 AS2856 British Telecommunications PLC 2.27ms from Erith, GB
81.143.68.38 AS2856 British Telecommunications PLC 2.72ms from Erith, GB
81.143.127.137 AS2856 British Telecommunications PLC 5.70ms from London, GB
81.143.213.179 AS2856 British Telecommunications PLC 1.55ms from London, GB
81.143.186.0 AS2856 British Telecommunications PLC 2.00ms from London, GB
81.143.87.254 AS2856 British Telecommunications PLC 17.18ms 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
80.94.177.140 AS12601 Cegedim.Cloud SASU 0.75ms from Aubervilliers, FR
24.147.102.28 AS7922 Comcast Cable Communications, LLC 4.89ms from Boston, US
74.125.66.236 AS396982 Google LLC 0.23ms from Chang-hua, TW
76.133.189.28 AS7922 Comcast Cable Communications, LLC 5.60ms from Fremont, US
168.70.51.252 AS4760 HKT Limited 0.82ms from Hong Kong, HK
206.51.55.204 AS397360 Texas State Technical College Harlingen 8.72ms from Houston, US
148.71.86.76 AS12353 Vodafone Portugal 2.10ms from Lisbon, PT
5.182.115.44 AS212683 Olilo UK & Ireland Ltd 0.41ms from London, GB
81.151.49.140 AS2856 British Telecommunications PLC 2.88ms from London, GB
86.156.230.44 AS2856 British Telecommunications PLC 1.12ms from London, GB
130.194.238.124 AS56132 Monash University, 2.14ms from Melbourne, AU
69.157.101.204 AS577 Bell Canada 1.86ms from Montreal, CA
70.127.175.124 AS33363 Charter Communications, Inc 8.57ms from Orlando, US
3.236.175.172 AS14618 Amazon.com, Inc. 0.18ms from Reston, US
125.179.235.12 AS17858 LG POWERCOMM 2.98ms from Seoul, KR
61.77.182.76 AS4766 Korea Telecom 1.51ms from Seoul, KR
20.8.134.204 AS8075 Microsoft Corporation 0.23ms from Amsterdam, NL
117.215.111.188 AS9829 National Internet Backbone 4.04ms from Bengaluru, IN
197.147.30.92 AS36884 Wana Corporate 9.63ms from Casablanca, MA
65.188.247.76 AS11426 Charter Communications Inc 8.83ms from Charlotte, US
160.223.171.252 AS40934 Fortinet Inc. 0.98ms from Dallas, US
71.195.161.44 AS7922 Comcast Cable Communications, LLC 5.19ms from Fremont, US
123.26.162.140 AS45899 VNPT Corp 3.69ms from Hanoi, VN
220.246.248.252 AS4760 HKT Limited 1.55ms from Hong Kong, HK
167.203.16.140 AS12701 Barclays Bank plc 2.98ms from London, GB

Traceroute

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

$
traceroute -a -n -q1 -f3 -m9 81.142.203.167
traceroute to 81.142.203.167 (81.142.203.167): 9 hops max, 52 byte packets
3 [AS42831] 5.101.143.16 4.229 ms
7 *
8 *
9 *
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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