asn.dev

Autonomous system

AS51377 COMASYS

Unclassified ARIN

IPv4 addresses 1.28K 2 prefixes
IPv6 prefixes 1 counted as prefixes, not addresses
Countries 1 mostly DK
Exchanges 0 recorded by PCH
Upstreams 1 0 downstream
Flagged prefixes 0 none

Summary

CoMaSys ApS

Denmark · AI-generated

business it-reseller denmark

COMASYS is operated by CoMaSys ApS, a Danish IT reseller and network solutions provider based in Odense.

What it's used for

  • The address space carries corporate and client infrastructure, evidenced by netnames DK-COMASYS1-20170629 and DK-COMASYS1-20050531 registered to NOC; CoMaSys ApS; Abuse-C Role.
  • The AS announces 1280 IPv4 addresses across 2 prefixes and 1 IPv6 prefix, with only 1 observed neighbour, indicating a small-scale access or internal corporate network rather than a transit provider.
  • Traffic consists of IT services for smaller businesses, including internet connectivity, VoIP, and cloud-based solutions, as described by the operator's service portfolio.

Notable

  • Registrants for both announced IPv4 prefixes align with the AS holder, listing CoMaSys ApS as the responsible entity.
  • The address inventory is compact, consisting of one /22 and one /24 block, consistent with a specialized IT service provider rather than a large-scale ISP.

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

Full topology · Graph

Internet exchanges

No exchange port on file. Many exchanges publish no participant list, so this is not proof of absence.

Transit providers

1 upstream, 0 downstream and 2 adjacent networks observed; most-used upstreams first.

ASNetworkPaths seen
AS34766atom86 BV325

Exchange presence is recorded rather than inferred: the directory collected by Packet Clearing House (https://www.pch.net/ixp/data) on 2026-10-20, licensed CC BY-NC-SA 3.0. Transit is inferred from observed BGP paths, never declared by either party.

Address space

Summary

Shape and geography

IPv4 2 prefixes · 1.28K addresses IPv6 1 prefixes

CountryNamePrefixes
DKDenmark3

Registry

Allocation record

ARIN · via Atlas (registry + RDAP)
Registry
ARIN
Handle
AS51377
Registry name
COMASYS
Registrant
lir-dk-comasys1-1-MNT
Abuse contact
abuse@comasys.dk
Registered
2017-08-03
Last changed
2025-04-22
Allocation
allocated

Routing security

RPKI and IRR

Full detail
RPKI
100% valid · 6 valid, 0 with no ROA
ROAs
4 authorising AS51377
ASPA
no ASPA record
IRR
100% registered · 6 of 6 announcements
Route objects
9 naming AS51377

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: 442 networks and 1,778 prefixes, as published 2026-10-20. 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

Cross-check