British Telecommunications PLC
United Kingdom
GB
66
announced
707,840
0 IPv6
RIPE
regional registry
Prefix size breakdown
Distribution of the 66 BGP prefixes announced by AS5400 grouped by CIDR length.
/16
6
/17
3
/18
4
/19
13
/20
4
/21
7
/22
5
/23
9
/24
15
First: 31.95.0.0/21 · Last: 213.236.64.0/18
Top cities by IPv4 footprint
Cities where AS5400's prefixes resolve, weighted by address count.
Düsseldorf
North Rhine-Westphalia, DE
38.9%
Frankfurt am Main
Hesse, DE
19.5%
Zurich
Zurich, CH
12.2%
Southampton
England, GB
4.9%
London
England, GB
4.9%
Announced prefixes
66 prefixes
Other ASNs in United Kingdom
Other ASNs run by British Telecommunications PLC
Verify on third-party BGP tools
Cross-check AS5400 on public looking-glass and BGP-data sites.
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