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
81.68.0.0/14 AS45090 Tencent Cloud Computing (Beijing) Co., Ltd 262,144
81.64.0.0/14 AS15557 Societe Francaise Du Radiotelephone - SFR SA 262,144
81.204.0.0/14 AS1136 KPN B.V. 262,144
81.76.0.0/14 AS5378 Vodafone Limited 262,144
81.60.0.0/15 AS12430 VODAFONE ONO, S.A. 131,072
81.82.0.0/15 AS6848 Telenet BV 131,072
81.62.0.0/15 AS3303 Swisscom (Schweiz) AG 131,072
81.164.0.0/15 AS6848 Telenet BV 131,072
81.178.0.0/15 AS13285 TalkTalk Communications Limited 131,072
81.56.0.0/15 AS29447 Free SAS 131,072
81.166.0.0/15 AS29695 Lyse Tele AS 131,072
81.182.0.0/15 AS5483 Magyar Telekom Plc. 131,072
81.218.0.0/16 AS8551 Bezeq International Ltd. 65,536
81.187.0.0/16 AS41489 Andrews & Arnold Ltd 65,536
81.192.0.0/16 AS6713 Office National des Postes et Telecommunications ONPT (Maroc Telecom) / IAM 65,536
81.80.0.0/16 AS3215 Orange S.A. 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
81.193.0.0/16 AS3243 MEO - SERVICOS DE COMUNICACOES E MULTIMEDIA S.A. 65,536
81.188.0.0/16 AS3257 GTT Communications Belgium N.V. 65,536
81.190.0.0/16 AS21021 Multimedia Polska Sp. z o.o. 65,536
81.187.0.0/16 AS20712 Andrews & Arnold Ltd 65,536
81.36.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.189.0.0/16 AS8437 Network of Hutchison Drei Austria GmbH 65,536
81.87.0.0/16 AS786 Jisc Services Limited 65,536
81.39.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.195.0.0/16 AS8359 MTS PJSC 65,536
81.126.0.0/16 AS3269 Telecom Italia S.p.A. 65,536
81.32.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.191.0.0/16 AS2116 GLOBALCONNECT AS 65,536
81.202.0.0/16 AS6739 Cableuropa - ONO 65,536
81.219.0.0/16 AS12741 Netia SA 65,536
81.35.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.198.0.0/16 AS24921 SIA Tet 65,536
81.221.0.0/16 AS1836 green.ch AG 65,536
81.198.0.0/16 AS12578 SIA Tet 65,536
81.38.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.37.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.81.0.0/16 AS1267 WIND TRE S.P.A. 65,536
81.33.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.61.0.0/16 AS6739 ONO_HFC 65,536
81.44.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.34.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.56.0.0/16 AS29447 Iliad / Free SAS 65,536
81.40.0.0/16 AS3352 Telefonica de Espana SAU 65,536
81.57.0.0/16 AS29447 Iliad / Free SAS 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

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

IP Address ASN Details
81.133.243.32 AS2856 British Telecommunications PLC 2.13ms from Erith, GB
81.134.214.6 AS2856 British Telecommunications PLC 0.75ms from London, GB
81.134.42.151 AS2856 British Telecommunications PLC 2.88ms from London, GB
81.134.222.38 AS2856 British Telecommunications PLC 0.85ms from London, GB
81.134.20.114 AS2856 British Telecommunications PLC 2.86ms from London, GB
81.134.116.116 AS2856 British Telecommunications PLC 0.99ms from London, GB
81.134.50.45 AS2856 British Telecommunications PLC 2.94ms from London, GB
81.134.217.82 AS2856 British Telecommunications PLC 0.83ms from London, GB
81.134.197.121 AS2856 British Telecommunications PLC 1.14ms from Erith, GB
81.134.52.173 AS2856 British Telecommunications PLC 3.28ms from Erith, GB
81.134.199.249 AS2856 British Telecommunications PLC 7.99ms from London, GB
81.134.44.32 AS2856 British Telecommunications PLC 2.96ms from London, GB
81.134.10.51 AS2856 British Telecommunications PLC 2.45ms from London, GB
81.134.242.109 AS2856 British Telecommunications PLC 1.20ms from London, GB
81.134.11.220 AS2856 British Telecommunications PLC 1.68ms from London, GB
81.133.214.142 AS2856 British Telecommunications PLC 2.45ms from London, GB
81.134.64.134 AS2856 British Telecommunications PLC 3.59ms from London, GB
81.134.18.164 AS2856 British Telecommunications PLC 2.68ms from London, GB
81.134.134.119 AS2856 British Telecommunications PLC 2.72ms from London, GB
81.134.196.82 AS2856 British Telecommunications PLC 1.03ms from London, GB
81.134.227.193 AS2856 British Telecommunications PLC 0.83ms from London, GB
81.134.202.28 AS2856 British Telecommunications PLC 1.57ms from London, GB
81.134.13.234 AS2856 British Telecommunications PLC 2.47ms from London, GB
81.134.107.238 AS2856 British Telecommunications PLC 1.64ms from London, GB
81.134.138.196 AS2856 British Telecommunications PLC 3.26ms 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
77.168.224.92 AS1136 KPN B.V. 2.30ms from Amsterdam, NL
20.120.17.124 AS8075 Microsoft Corporation 0.39ms from Ashburn, US
97.149.32.108 AS6167 Verizon Business 11.80ms from Chicago, US
73.208.58.12 AS7922 Comcast Cable Communications, LLC 5.87ms from Chicago, US
14.228.194.220 AS45899 VNPT Corp 5.62ms from Hanoi, VN
78.189.54.140 AS9121 Turk Telekomunikasyon Anonim Sirketi 1.70ms from Istanbul, TR
167.203.16.140 AS12701 Barclays Bank plc 2.88ms from London, GB
3.166.48.204 AS16509 Amazon.com, Inc. 0.39ms from London, GB
95.168.185.188 AS205544 Leaseweb UK Limited 0.58ms from London, GB
81.129.173.188 AS2856 British Telecommunications PLC 6.09ms from London, GB
114.188.77.12 AS4713 NTT DOCOMO BUSINESS,Inc. 5.17ms from Osaka, JP
83.108.141.204 AS2119 Telenor Norge AS 2.51ms from Oslo, NO
86.107.117.236 AS21409 Ikoula Net SAS 0.72ms from Reims, FR
3.226.118.124 AS14618 Amazon.com, Inc. 0.14ms from Reston, US
83.140.231.12 AS12552 GlobalConnect AB 0.84ms from Stockholm, SE
36.52.60.108 AS10013 FreeBit Co.,Ltd. 4.80ms from Tokyo, JP
2.135.200.124 AS9198 JSC Kazakhtelecom 13.40ms from Karagandy, KZ
172.90.131.188 AS20001 Charter Communications Inc 5.72ms from Los Angeles, US
91.118.207.220 AS8412 T-Mobile Austria GmbH 3.53ms from Vienna, AT
185.45.113.108 AS29141 Bradler & Krantz GmbH & Co. KG 0.82ms from Amsterdam, NL
62.234.1.44 AS45090 Shenzhen Tencent Computer Systems Company Limited 1.93ms from Beijing, CN
73.208.136.44 AS7922 Comcast Cable Communications, LLC 4.07ms from Chicago, US
201.94.243.108 AS22689 SERCOMTEL S/A TELECOMUNICACOES 5.77ms from Curitiba, BR
79.125.121.76 AS16509 Amazon.com, Inc. 0.18ms from Dublin, IE
40.143.167.76 AS17378 TierPoint, LLC 1.75ms from Durham, US

Traceroute

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

$
traceroute -a -n -q1 -m10 81.128.142.34
traceroute to 81.128.142.34 (81.128.142.34): 10 hops max, 52 byte packets
1 [AS198037] 80.71.227.1 0.174 ms
3 *
4 *
5 *
6 *
7 [AS2856] 109.159.254.9 11.605 ms
8 *
9 *
10 *
Measurement taken from IPinfo ProbeNet in Meppel, NL
On

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