Autonomous system
AS15457 NOS_MADEIRA
Unclassified RIPE
Summary
NOS Madeira
isp telecom media infrastructure
The reverse zone is split by the first octet, and the subdomain says which one.
What it's used for
- An island cable television and internet operator. Eight IPv4 prefixes and one IPv6
/29announced from Portugal, sixty-nine thousand addresses, through one observed BGP neighbour.
Notable
- Every one of the fifteen answering addresses takes the same form: the four octets in dashes, then a subdomain made of the letters for pointer record and the address's own first octet, then the company domain.
- Seven of the eight blocks are the same size, and each netname carries the country code, a former cable television brand, and its allocation date.
- Those dates run across more than a decade, one block roughly every eighteen months.
- The abuse contact is written as a lower case string with a dot in it, shaped like a domain rather than a name.
- Eighteen addresses were queried for reverse DNS and fifteen returned a name.
Interesting
- Partitioning the reverse zone by first octet is a practical answer to holding blocks from eight unrelated ranges. Each range gets its own subtree and they never collide.
- Cable operators became internet providers by laying the same coaxial they already had, and the old brand surviving in every netname is the record of that.
- Sixty-nine thousand addresses behind one observed neighbour is the exposure worth naming. An island network with one path is one cable away from being cut off.
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
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.
| AS | Network | Paths seen |
|---|---|---|
| AS2860 | NOS COMUNICACOES, S.A. | 513 |
Exchange presence is recorded rather than inferred: the directory collected by Packet Clearing House (https://www.pch.net/ixp/data) on 2026-10-31, licensed CC BY-NC-SA 3.0. Transit is inferred from observed BGP paths, never declared by either party.
Address space
Summary
IPv4 8 prefixes · 69.63K addresses IPv6 1 prefixes
| Country | Name | Prefixes |
|---|---|---|
| PT | Portugal | 9 |
Registry
Allocation record
- Registry
- RIPE
- Handle
AS15457- Registry name
- NOS_MADEIRA
- Registrant
- AS15457-MNT
- Abuse contact
- abuse@cabotvm.pt
- Registered
- 1970-01-01
- Last changed
- 2017-11-15
- Allocation
- allocated
Routing security
RPKI and IRR
- RPKI
- 100% valid · 9 valid, 0 with no ROA
- ROAs
- 12 authorising AS15457
- ASPA
- no ASPA record
- IRR
- 100% registered · 9 of 9 announcements
- Route objects
- 12 naming AS15457
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 1,845 prefixes, as published 2026-10-31. 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