81.133.208.19
An address in London, England, United Kingdom, announced by British Telecommunications Limited (AS2856). It's mobile carrier space of BT, a mail server on port 587, a DNS server on port 53, and a web server on ports 80 and 443.
Summary
Geolocation
Where the address is, and what that place uses.
- City
- London
- Region
- England
- Postal code
- E1W
- Country
- United Kingdom
- Continent
- Europe
- Coordinates
- 51.5085, -0.1257
- Timezone
- Europe/London
Ownership
Who holds the address: the AS announcing it, the registry record, the abuse contact and its name in DNS.
- Company
- British Telecommunications Limited
- Domain
- bt.net
- Type
- ISP
- Registered in
- United Kingdom
- AS number
- AS2856
- Name
- British Telecommunications Limited
- Prefix
- 81.128.0.0/12
- RPKI
- Valid
- Type
- ISP
- Domain
- bt.net
- Registered in
- United Kingdom
- Name
- Single Static IP addresses
- Network name
- BT-ADSL
- Status
- ASSIGNED PA
- Registry
- RIPE NCC
- Domain
- btopenworld.com
- Name
- Abuse-C Role
- abuse@bt.com
- Address
- BT Public Internet Service
- Network
- 81.128.0.0-81.159.255.255
Anonymity
Whether the address hides someone else: a VPN, Tor, a relay, a proxy pool, or a hosting range.
Network
What kind of network it is on: a mobile carrier, a satellite operator, an anycast service, a CDN edge.
Services
What our own internet-wide measurement found listening on it.
- Port
- 587
- Banner
- 220 jayne.kieransimkin.co.uk ESMTP Postfix (Ubuntu)
- Greeting
- Completed
- First seen
- 2026-08-13
- Last seen
- 2026-10-20
- Port
- 53
- Recursion
- Refused
- Response code
- 5
- Answer
- Wrong
- First seen
- 2026-08-07
- Last seen
- 2026-10-30
- 80 status
- 301
- 80 redirect
- https://kieransimkin.co.uk/
- 80 server
- nginx
- 80 title
- 301 Moved Permanently
- 80 seen
- 2026-08-10 to 2026-10-26
- 443 status
- 301
- 443 redirect
- https://clg.wtf/
- 443 server
- nginx
- 443 title
- 301 Moved Permanently
- 443 TLS
- TLSv1.3
- 443 certificate
- www.clg.wtf
- 443 issuer
- C=US, O=Let's Encrypt, CN=YE1
- 443 browser-trusted
- Yes
- 443 seen
- 2026-08-02 to 2026-10-24
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