All ASNs

Autonomous System details for AS2856

AS2856

British Telecommunications Limited • bt.com

AS2856 — British Telecommunications Limited

AS Name

BT-UK-AS

Country

United Kingdom (GB)

Website

bt.com

Number of IPv4

18,402,560

Number of IPv6

1.08 × 10³¹

ASN type

ISP

Status

Allocated

Registry

RIPE

Allocated

August 30, 2002

Last updated

July 21, 2026

IP Ranges

486 IPv4 prefixes, 6 IPv6 prefixes

Prefix	Company	Number of IPs
5.35.192.0/21	Lunarnaut, LLC	2,048
5.80.0.0/15	British Telecommunications PLC	131,072
5.81.0.0/16	BT Infrastructure Layer	65,536
5.181.136.0/24	Motorola Solutions UK Ltd	256
9.151.0.0/19	WC UK Limited	8,192
9.151.208.0/20	BT AS2856	4,096
9.151.248.0/21	London, England	2,048
9.233.48.0/20	British Telecommunications	4,096
9.237.96.0/19	London, England	8,192
9.237.128.0/18	British Telecommunications	16,384
9.237.192.0/19	London, England	8,192
15.145.20.0/22	Amazon Data Services UK	1,024
23.26.70.0/24	Ace Data Centers, Inc.	256
23.26.108.0/24	Ace Data Centers, Inc.	256
23.26.117.0/24	Ace Data Centers, Inc.	256
23.26.131.0/24	Ace Data Centers, Inc.	256
23.26.192.0/24	Ace Data Centers, Inc.	256
23.27.32.0/24	Ace Data Centers II, L.L.C.	256
23.27.33.0/24	Ace Data Centers II, L.L.C.	256
23.27.34.0/24	Ace Data Centers II, L.L.C.	256
23.27.35.0/24	Ace Data Centers II, L.L.C.	256
23.27.36.0/24	Ace Data Centers II, L.L.C.	256
23.27.37.0/24	Ace Data Centers II, L.L.C.	256
23.27.38.0/24	Ace Data Centers II, L.L.C.	256
23.27.39.0/24	Ace Data Centers II, L.L.C.	256
23.27.40.0/24	Ace Data Centers II, L.L.C.	256
23.27.102.0/24	Ace Data Centers II, L.L.C.	256
23.27.103.0/24	Ace Data Centers II, L.L.C.	256
23.27.104.0/24	Ace Data Centers II, L.L.C.	256
23.27.105.0/24	Ace Data Centers II, L.L.C.	256
23.27.106.0/24	Ace Data Centers II, L.L.C.	256
23.27.107.0/24	Ace Data Centers II, L.L.C.	256
23.27.108.0/24	Ace Data Centers II, L.L.C.	256
23.230.82.0/23	EGIHosting	512
23.230.242.0/24	EGIHosting	256
23.230.252.0/24	EGIHosting	256
31.48.0.0/13	BT Infrastructure Layer	524,288
31.90.0.0/15	EE Limited	131,072
31.92.0.0/15	EEMobile	131,072
31.94.0.0/16	EE MOBILE	65,536
31.96.0.0/16	BTNET 3	65,536
31.100.0.0/14	EE Limited	262,144
31.104.0.0/16	British Telecommunications PLC	65,536
31.106.0.0/15	EE Limited	131,072
31.112.0.0/14	EE Limited	262,144
31.116.0.0/14	EE Limited	262,144
31.116.0.0/16	EE Limited	65,536
31.117.0.0/16	EE Limited	65,536
31.118.0.0/16	EE Limited	65,536
31.119.0.0/16	BTnet Assignments	65,536
31.120.0.0/16	BTNET 3	65,536
31.121.0.0/16	BTnet Assignments	65,536
31.122.0.0/15	EE Limited	131,072
31.124.0.0/16	EE Limited	65,536
31.126.0.0/15	British Telecommunications Limited	131,072
31.130.240.0/23	Global Router LLC	512
37.44.229.0/24	IPXO	256
37.44.230.0/24	Netwise Hosting Ltd	256
37.44.231.0/24	IPXO	256
37.97.112.0/22	GVM Sistem 2003 SRL	1,024
37.143.0.0/22	WeePee NV	1,024
37.230.61.0/24	Private Customer	256
40.27.28.0/24	Internet Utilities NA LLC	256
40.27.72.0/24	Private Customer	256
45.39.116.0/24	Subnet Digital LLC	256
45.39.188.0/24	Subnet Digital LLC	256
45.149.7.0/24	Droptop GmbH	256
45.149.168.0/23	CPS Internetworking BV	512
45.149.170.0/23	Internet Utilities Europe and Asia Limited	512
46.68.0.0/15	EE Limited	131,072
46.68.66.0/24	EE Limited	256
46.248.96.0/22	Burstfire Networks Ltd	1,024
46.248.102.0/23	BTNET LHL	512
46.248.104.0/23	BTNET LHL	512
46.248.120.0/22	BTNET LHL	1,024
50.117.7.0/24	EGIHosting	256
50.117.51.0/24	EGIHosting	256
50.118.154.0/23	Internet Utilities NA LLC	512
51.14.0.0/16	British Telecommunications PLC	65,536
51.64.32.0/24	UK Home Office (The Secretary of State for the Home Department)	256
51.64.34.0/24	UK Home Office (The Secretary of State for the Home Department)	256
51.64.35.0/24	UK Home Office (The Secretary of State for the Home Department)	256
51.146.44.0/22	Sky UK Limited	1,024
51.146.128.0/22	Sky UK Limited	1,024
51.146.136.0/22	Sky UK Limited	1,024
51.146.235.0/24	Private Customer	256
51.146.252.0/22	Private Customer	1,024
51.149.18.0/24	Cabinet Office	256
51.149.19.0/24	Cabinet Office	256
51.194.36.0/23	Private Customer	512
51.194.100.0/22	Private Customer	1,024
51.230.0.0/20	Department for Work and Pensions	4,096
51.230.16.0/20	Department for Work and Pensions	4,096
51.230.32.0/20	Department for Work and Pensions	4,096
51.230.48.0/20	Department for Work and Pensions	4,096
51.230.64.0/20	Department for Work and Pensions	4,096
51.230.80.0/20	Department for Work and Pensions	4,096
51.230.96.0/20	Department for Work and Pensions	4,096
51.230.112.0/20	Department for Work and Pensions	4,096
51.230.255.0/24	UK DWP	256
2001:4878:c259::/48	Akamai Technologies, Inc.	1.21 × 10²⁴
2a00:2380::/25	British Telecommunications PLC	1.01 × 10³¹
2a01:4c8::/29	EE Limited	6.34 × 10²⁹
2a01:4c8:f400::/48	EE Limited	1.21 × 10²⁴
2a01:4c8:f401::/48	EE Limited	1.21 × 10²⁴
2a03:1e82:90ff::/48	BMW UK	1.21 × 10²⁴

This table only shows the first 100 of the set of IPv4 and IPv6 prefixes. All data is available via our IP data API.

IP ranges are the different blocks of IP addresses advertised by an Autonomous System (AS). These ranges can be used by the same organization operating the AS, or by different organizations.

Peers of AS2856

89 peers

AS249 AS702 AS786 AS1267 AS1828 AS2686 AS3170 AS3303 AS4455 AS4766 AS5089 AS5405 AS5413 AS6206 AS6461 AS6908 AS7979 AS8220 AS8426 AS8607 AS8657 AS8681 AS8757 AS8966 AS9002 AS9505 AS12200 AS12713 AS13009 AS13030 AS13213 AS13237 AS15830 AS16265 AS16276 AS16509 AS17639 AS19551 AS20253 AS20860 AS25198 AS25369 AS25577 AS30058 AS30740 AS30844 AS31727 AS32590 AS33353 AS35266 AS39122 AS41107 AS41354 AS41811 AS42473 AS43519 AS44444 AS47480 AS48185 AS50245 AS50304 AS51185 AS57356 AS60068 AS61049 AS61323 AS62044 AS62240 AS137409 AS199524 AS201126 AS206067 AS215638 AS215724 AS396356 AS6424 AS6667 AS8359 AS8468 AS8781 AS9009 AS15557 AS31898 AS42689 AS48070 AS49544 AS50300 AS60439 AS212655

AS2856 peers with these other Autonomous Systems.

Peering is a direct, often free, traffic exchange between Autonomous Systems (ASNs). They share routes only to their own networks and customers, making connections faster and cheaper for that specific traffic, without providing full internet access to each other.

Upstreams of AS2856

3 upstreams

AS5400 AS25180 AS56595

AS2856 uses these Autonomous Systems as its upstreams.

An upstream (or transit provider) is another AS that AS2856 pays for full internet connectivity, allowing it to reach all global destinations and be reachable by them.

Downstreams of AS2856

147 downstreams

AS72 AS2134 AS2535 AS3738 AS5091 AS6871 AS7358 AS8336 AS8435 AS9011 AS11031 AS11528 AS11939 AS12222 AS12440 AS13205 AS13458 AS14630 AS14766 AS14931 AS15141 AS15248 AS15499 AS15865 AS16477 AS16525 AS16839 AS17274 AS17903 AS19239 AS19305 AS19428 AS19812 AS20163 AS20464 AS20705 AS21054 AS21110 AS21218 AS21296 AS21301 AS21369 AS21464 AS21470 AS21758 AS22775 AS24775 AS25049 AS25050 AS25343 AS25421 AS28690 AS28863 AS29033 AS29888 AS31003 AS33001 AS33127 AS33442 AS33680 AS33981 AS35350 AS35707 AS36224 AS38191 AS38936 AS39550 AS39552 AS39957 AS41373 AS41380 AS41570 AS41839 AS41988 AS42536 AS43259 AS44268 AS44371 AS44480 AS44617 AS47113 AS47534 AS48549 AS48688 AS49318 AS50203 AS50826 AS50948 AS51953 AS53926 AS54113 AS55290 AS56644 AS56745 AS57002 AS59345 AS59445 AS59451 AS60339 AS60925 AS60962 AS63112 AS63399 AS131993 AS197409 AS198032 AS198386 AS199262 AS199675 AS200961 AS201536 AS202206 AS202275 AS202466 AS202907 AS203133 AS203171 AS204322 AS204550 AS205114 AS205693 AS206051 AS206146 AS206166 AS206237 AS206467 AS206686 AS207087 AS207273 AS207552 AS209258 AS209761 AS209997 AS210988 AS211015 AS211077 AS211303 AS211389 AS212329 AS212565 AS213786 AS213867 AS213885 AS393414 AS394265 AS394731 AS395959

AS2856 provides internet connectivity to these downstream Autonomous Systems.

A downstream is a customer Autonomous System that pays another AS (its provider) for internet access. The provider AS carries the downstream's traffic and makes its network reachable.