Autonomous system
AS21574 Century Telecom Ltda
Unclassified LACNIC
Summary
Century Telecom
isp brazil residential telecom
AS21574 is operated by Century Telecom Ltda.
What it's used for
- The address space carries residential and business internet access, evidenced by reverse DNS records pointing to
centurytelecom.net.brand specific subnets likerede-precon.centurytelecom.net.br. - The AS announces 13,312 IPv4 addresses across 8 prefixes and 1 IPv6 prefix, while maintaining 249 observed neighbours. This high neighbour count relative to the address inventory indicates a role focused on transit and peering for a regional Brazilian ISP.
Notable
- All registrants for the announced prefixes are listed as Century Telecom Ltda, matching the AS holder name.
- The address inventory is composed of multiple /20, /21, /22, /23, and /24 blocks, with the largest being 186.249.224.0/20 and 200.169.0.0/20.
- The network has been observed in routing tables since 2001-06-15.
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 9 exchanges in 3 countries, largest first.
| Exchange | Location | Their address |
|---|---|---|
| IX.br (PTT.br) São Paulo | São Paulo, Brazil | 187.16.216.26 |
| DE-CIX Frankfurt | Frankfurt, Germany | 80.81.192.102 |
| IX.br (PTT.br) Fortaleza | Fortaleza, Brazil | 45.68.73.63 |
| IX.br (PTT.br) Porto Alegre | Porto Alegre, Brazil | 177.52.39.32 |
| DE-CIX New York | New York, United States | 206.82.105.113 |
| IX.br (PTT.br) Curitiba | Curitiba, Brazil | 45.184.146.11 |
| IX.br (PTT.br) Florianópolis | Florianópolis, Brazil | 200.219.141.115 |
| IX.br (PTT.br) Belo Horizonte | Belo Horizonte, Brazil | 200.219.139.117 |
Transit providers
28 upstream, 106 downstream and 236 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 2026-10-11, 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 · 13.31K addresses IPv6 1 prefixes
| Country | Name | Prefixes |
|---|---|---|
| BR | Brazil | 9 |
Registry
Allocation record
- Registry
- LACNIC
- Registered
- 2001-06-07
- Allocation
- allocated
Routing security
RPKI and IRR
- RPKI
- 0% valid · 0 valid, 7 with no ROA
- ROAs
- 0 authorising AS21574
- ASPA
- no ASPA record
- IRR
- 100% registered · 7 of 7 announcements
- Route objects
- 11 naming AS21574
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: 432 networks and 1,768 prefixes, as published 2026-10-12. 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