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
81.68.0.0/14 AS45090 Tencent Cloud Computing (Beijing) Co., Ltd 262,144
81.204.0.0/14 AS1136 KPN B.V. 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
81.212.0.0/14 AS9121 Turk Telekomunikasyon Anonim Sirketi 262,144
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
81.166.0.0/15 AS29695 Lyse Tele AS 131,072
81.182.0.0/15 AS5483 Magyar Telekom Plc. 131,072
81.60.0.0/15 AS12430 VODAFONE ONO, S.A. 131,072
81.178.0.0/15 AS13285 TalkTalk Communications Limited 131,072
81.56.0.0/15 AS29447 Free SAS 131,072
81.220.0.0/16 AS15557 Societe Francaise Du Radiotelephone - SFR SA 65,536
81.39.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.187.0.0/16 AS41489 Andrews & Arnold Ltd 65,536
81.223.0.0/16 AS8412 T-Mobile Austria GmbH 65,536
81.84.0.0/16 AS2860 NOS COMUNICACOES, S.A. 65,536
81.34.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.198.0.0/16 AS12578 SIA Tet 65,536
81.198.0.0/16 AS24921 SIA Tet 65,536
81.189.0.0/16 AS8437 Network of Hutchison Drei Austria GmbH 65,536
81.36.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.81.0.0/16 AS1267 WIND TRE S.P.A. 65,536
81.35.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.219.0.0/16 AS12741 Netia SA 65,536
81.40.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.38.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.221.0.0/16 AS1836 green.ch AG 65,536
81.185.0.0/16 AS15557 Societe Francaise Du Radiotelephone - SFR SA 65,536
81.191.0.0/16 AS2116 GLOBALCONNECT AS 65,536
81.44.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.216.0.0/16 AS1257 Tele2 Sverige AB 65,536
81.37.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.56.0.0/16 AS29447 Iliad / Free SAS 65,536
81.86.0.0/16 AS13285 TalkTalk Communications Limited 65,536
81.194.0.0/16 AS2200 Renater 65,536
81.57.0.0/16 AS29447 Iliad / Free SAS 65,536
81.32.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.192.0.0/16 AS6713 Office National des Postes et Telecommunications ONPT (Maroc Telecom) / IAM 65,536
81.33.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.195.0.0/16 AS8359 MTS PJSC 65,536
81.184.0.0/16 AS6739 VODAFONE ONO, S.A. 65,536
81.187.0.0/16 AS20712 Andrews & Arnold Ltd 65,536
81.188.0.0/16 AS3257 GTT Communications Belgium N.V. 65,536
81.193.0.0/16 AS3243 MEO - SERVICOS DE COMUNICACOES E MULTIMEDIA S.A. 65,536
81.87.0.0/16 AS786 Jisc Services Limited 65,536

Hosted domains

There are 3,700 domain names hosted across 1,657 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 asimpleroom.co.uk 109
81.128.160.145 hawkmad.com 60
81.128.239.117 thedrinksreport.co.uk 60
81.136.181.36 sapws.net 59
81.133.245.70 expressroofinghomeimprovements.co.uk 50
81.130.171.229 hartwell.london 30
81.133.74.88 cornerstone.systems 29
81.128.250.13 carrwoodhousedental.co.uk 26
81.139.48.154 isisconveyancing.com 25
81.143.201.172 epos-web.com 23
81.143.221.131 borg.help 20
81.133.228.187 pitt-stop.wales 19
81.128.160.188 hudsmail.co.uk 19
81.128.140.142 reparation-ordinateur-portable-fujitsu.fr 17
81.128.167.213 hypertec-ltd.co.uk 17
81.128.173.172 sufix.co.uk 16
81.128.245.172 ukbusinessregistry.co.uk 16
81.137.54.177 yachtchandleronline.com 16
81.130.179.42 ever-rosedesignco.co.uk 15
81.130.165.202 shoeempire.co.uk 15

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

370,858 IPs in this range replied to an ICMP ping during our most recent internet scan. Learn more.

IP Address ASN Details
81.141.168.47 AS2856 British Telecommunications PLC 4.05ms from London, GB
81.142.96.238 AS2856 British Telecommunications PLC 5.81ms from London, GB
81.142.102.94 AS2856 British Telecommunications PLC 6.47ms from London, GB
81.142.175.234 AS2856 British Telecommunications PLC 4.18ms from London, GB
81.141.147.37 AS2856 British Telecommunications PLC 6.29ms from London, GB
81.142.160.203 AS2856 British Telecommunications PLC 5.37ms from London, GB
81.142.113.83 AS2856 British Telecommunications PLC 6.17ms from London, GB
81.142.41.134 AS2856 British Telecommunications PLC 6.21ms from London, GB
81.141.217.20 AS2856 British Telecommunications PLC 1.90ms from London, GB
81.142.145.22 AS2856 British Telecommunications PLC 12.88ms from London, GB
81.141.200.60 AS2856 British Telecommunications PLC 2.23ms from London, GB
81.141.211.107 AS2856 British Telecommunications PLC 4.05ms from London, GB
81.141.202.109 AS2856 British Telecommunications PLC 3.64ms from London, GB
81.142.50.165 AS2856 British Telecommunications PLC 4.55ms from London, GB
81.141.215.16 AS2856 British Telecommunications PLC 2.83ms from London, GB
81.141.157.132 AS2856 British Telecommunications PLC 5.82ms from London, GB
81.141.254.19 AS2856 British Telecommunications PLC 1.98ms from London, GB
81.142.150.182 AS2856 British Telecommunications PLC 7.25ms from London, GB
81.141.206.179 AS2856 British Telecommunications PLC 5.26ms from London, GB
81.142.178.250 AS2856 British Telecommunications PLC 6.13ms from London, GB
81.141.187.143 AS2856 British Telecommunications PLC 5.44ms from London, GB
81.142.143.148 AS2856 British Telecommunications PLC 4.82ms from London, GB
81.142.59.214 AS2856 British Telecommunications PLC 10.93ms from London, GB
81.141.227.122 AS2856 British Telecommunications PLC 4.46ms from London, GB
81.141.132.82 AS2856 British Telecommunications PLC 12.61ms 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
174.49.102.156 AS7922 Comcast Cable Communications, LLC 4.28ms from Atlanta, US
84.195.68.44 AS6848 Telenet BV 5.00ms from Brussels, BE
117.60.143.76 AS4134 CHINANET-BACKBONE 5.99ms from Huai'an, CN
82.97.251.156 AS9123 JSC "TIMEWEB" 0.70ms from Moscow, RU
97.104.185.60 AS33363 Charter Communications, Inc 6.23ms from Orlando, US
110.134.29.108 AS9824 JCOM Co., Ltd. 17.92ms from Osaka, JP
138.91.248.44 AS8075 Microsoft Corporation 0.56ms from San Jose, US
36.141.127.252 AS9808 China Mobile Communications Group Co., Ltd. 3.85ms from Shenzhen, CN
79.118.77.92 AS8708 DIGI ROMANIA S.A. 2.92ms from Timisoara, RO
91.115.77.108 AS8447 A1 Telekom Austria AG 9.16ms from Vienna, AT
185.154.100.12 AS20988 MTF Solutions AG 0.80ms from Zuerich, CH
52.190.62.172 AS8075 Microsoft Corporation 0.44ms from Ashburn, US
175.11.193.12 AS4134 CHINANET-BACKBONE 1.67ms from Changsha, CN
18.223.112.28 AS16509 Amazon.com, Inc. 1.00ms from Columbus, US
34.247.1.124 AS16509 Amazon.com, Inc. 0.17ms from Dublin, IE
92.216.52.156 AS3209 Vodafone GmbH 5.93ms from Frankfurt am Main, DE
195.135.189.252 AS8469 CANCOM Managed Services GmbH 8.36ms from Frankfurt am Main, DE
137.74.175.60 AS16276 OVH SAS 0.20ms from Gravelines, FR
202.55.42.252 AS9304 HGC Global Communications Limited 0.97ms from Hong Kong, HK
190.238.173.220 AS6147 Telefonica del Peru S.A.A. 1.01ms from Lima, PE
151.112.130.188 AS32480 Loma Linda University Medical Center 3.04ms from Los Angeles, US
98.2.253.108 AS11351 Charter Communications Inc 12.85ms from New York City, US
58.3.70.60 AS7679 QTnet,Inc. 9.67ms from Osaka, JP
60.211.86.44 AS4837 CHINA UNICOM China169 Backbone 7.84ms from Qingdao, CN
188.233.103.252 AS39435 JSC ER-Telecom Holding 10.83ms from Samara, RU

Traceroute

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

$
traceroute -a -n -q1 -f2 81.143.255.134
traceroute to 81.143.255.134 (81.143.255.134): 64 hops max, 52 byte packets
3 *
4 *
5 [] 64.130.60.88 11.089 ms
6 *
7 [AS174] 154.54.73.242 11.081 ms
8 [AS5400] 166.49.209.130 12.191 ms
9 [AS5400] 166.49.209.133 12.355 ms
10 *
11 *
12 [AS2856] 213.120.163.217 12.169 ms
13 [AS2856] 81.143.255.134 24.782 ms
Measurement taken from IPinfo ProbeNet in Dublin, IE
On

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