Autonomous system
AS51561 AS-ICUK
Unclassified RIPE NSP
Summary
ICUK
wholesale isp uk connectivity
AS-ICUK is operated by ICUK Computing Services Limited.
What it's used for
- The address space carries residential and business connectivity, evidenced by reverse DNS entries such as
default-188-240-183-254.interdsl.co.ukanddefault-205-157-183-254.interdsl.co.uk. - The AS announces 72,448 IPv4 addresses across 63 prefixes and 17 IPv6 prefixes, while maintaining 96 observed neighbours, a ratio consistent with a wholesale network provider.
- As a wholesale platform, the traffic consists of rebranded connectivity, telecoms, and web hosting solutions provided to resellers and business clients.
Notable
- All sampled registrants align with the announcer, listing
ICUK Ripe AdministratorandICUK Computing Services Limitedfor prefixes including188.240.160.0/19and205.157.160.0/19. - The inventory is finely subdivided into numerous /20, /21, and /22 blocks, reflecting a segmented corporate estate rather than a single monolithic allocation.
This description is AI-generated, best-effort context — not authoritative, and provided without any guarantee of accuracy. Source, and how to suggest an edit.
Interconnection
Peering at a glance
Internet exchanges
Recorded at 2 exchanges in 1 country, largest first.
| Exchange | Location | Their address |
|---|---|---|
| LINX LON1 | London, United Kingdom | 195.66.226.191 |
| London Network Access Point | London, United Kingdom | 5.57.81.134 |
Transit providers
24 upstream, 2 downstream and 35 adjacent networks observed; most-used upstreams first.
Exchange presence is recorded rather than inferred: the directory collected by Packet Clearing House (https://www.pch.net/ixp/data) on 2026-10-27, licensed CC BY-NC-SA 3.0. Transit is inferred from observed BGP paths, never declared by either party.
Address space
Summary
IPv4 61 prefixes · 73.22K addresses IPv6 17 prefixes
| Country | Name | Prefixes |
|---|---|---|
| GB | United Kingdom | 78 |
Registry
Allocation record
- Registry
- RIPE
- Handle
AS51561- Registry name
- AS-ICUK
- Registrant
- ICUK-MNT
- Abuse contact
- abuse@interdns.co.uk
- Registered
- 2010-09-28
- Last changed
- 2026-02-24
- Allocation
- allocated
Declared
PeeringDB profile
- Name
- ICUK Computing Services Ltd
- Also known as
- ICUK.net
- Network type
- NSP
- Scope
- Europe
- Traffic ratio
- Mostly Inbound
- Peering policy
- Open
- IRR as-set
AS-ICUK- Present at
- 3 exchanges
- Facilities
- 3 facilities
- Website
- https://www.icuk.net/
PeeringDB records are maintained by the network operator and are not independently verified. Treat them as a statement of intent rather than of fact. For the observed and recorded view, see peering, which lists the exchanges Packet Clearing House has a port on file for.
Routing security
RPKI and IRR
- RPKI
- 11% valid · 8 valid, 66 with no ROA
- ROAs
- 10 authorising AS51561
- ASPA
- no ASPA record
- IRR
- 100% registered · 74 of 74 announcements
- Route objects
- 74 naming AS51561
Reputation
Classification and threat
Unclassified Not in the curated lists. Most of the ~80,000 allocated ASNs are not.
Spamhaus DROP
Not on ASN-DROP The network as a whole is not listed.
No DROP prefixes None of its announced space is on the DROP prefix list.
Spamhaus DROP ("Don't Route Or Peer") lists space and networks run by, or hijacked for, spam and cybercrime operations: 447 networks and 1,852 prefixes, as published 2026-10-27. A short, high-confidence list, so a match is worth taking seriously, and absence from it says little on its own.
FBI IC3
No IC3 indicators Nothing from the FBI IC3 feed.
IC3 threat data is alpha. Absence of an indicator is not evidence of good behaviour, only of absence from this one feed.
Elsewhere