subnet.im

AS21574Century Telecom Ltda

BrazilRegistryLACNICTypeEyeball

As of 14th November 2026, AS21574 (Century Telecom Ltda), an access network registered in Brazil with LACNIC, originates 8 IPv4 prefixes covering 16.1k addresses and 1 IPv6 prefix. By IPv4 address space that makes it the 8,367th-largest of the 80,840 networks we see originating IPv4, and the 479th-largest of 8,036 in Brazil. It is seen behind 26 upstream networks, most often AS263444 (Open X Tecnologia Ltda) and AS7195 (EdgeUno), and in front of 107 downstream networks. None of its announcements have a valid RPKI ROA. 56% of its routes reach at least 90% of full-feed peers.

At a glance

IPv4 prefixes

8

IPv6 prefixes

1

IPv4 addresses

16.1k

IPv6 /64s

4.3B

Upstream graph

The networks AS21574 is seen behind, one and two hops out, drawn from real AS paths.

AS21574Toward the internet core
Upstream graph for AS21574: 12 neighbouring networks observed beyond it across 2 levels. The same networks are listed in the tables below.AS21574Century Telecom L…This networkAS1031PEER 1031 LLCAS3356Lumen (Level 3)AS7195EdgeUnoAS263444Open X Tecnologia…AS267613ELETRONET S.A.AS999CORIX NETWORKSAS6453TATA Communicatio…AS1299Arelion (fka. Tel…AS2914NTT America, Inc.AS32590Valve CorporationAS57463NetIX Communicati…AS13786Seaborn (Seabras …

Networks observed one and two hops upstream of AS21574 in real AS paths. A thicker line means more vantage points saw that adjacency, so weight tracks how well attested it is — not how much traffic it carries. Adjacency is an observation; whether it is a transit purchase or a settlement-free peering is an inference, and is labelled as one wherever we show it.

Neighbouring networks

316

adjacent networks

Upstreams
268%
Peers
18358%
Downstreams
10734%

Networks carrying this one's traffic toward the rest of the internet.

Upstreams of AS21574
NetworkCountryRelationshipPathsVantage pts
AS263444Open X Tecnologia LtdaBRPeer8,936127
AS7195EdgeUnoCOPeer7,279117
AS267613ELETRONET S.A.BRPeer3,30481
AS1031PEER 1031 LLCUSPeer2,62342
AS3356Lumen (Level 3)USPeer1,28499
AS6939Hurricane Electric LLCUSPeer94532
AS1000LINK AMERICANUSPeer5792
AS13786Seaborn (Seabras USA, LLC)USPeer50828
AS32590Valve CorporationUSPeer3952
AS35280F5 Networks SARLFRPeer3285

Prefixes

The largest blocks AS21574 originates, widest first.

Largest prefixes originated by AS21574
PrefixAddressesVisibility
186.249.224.0/204.1k78/78
187.1.176.0/204.1k78/78
200.169.0.0/204.1k78/78
200.169.8.0/212k1/78
168.227.200.0/221k78/78
187.1.176.0/242562/78
187.1.177.0/2425657/78
187.1.178.0/2425621/78
2804:23ec::/324.3B × /6464/64

Routing health

How AS21574's own announcements validate against RPKI and how far they propagate. The same measures for the whole routing table are on the routing table in numbers.

RPKI origin validation

  • Valid0.0%0
  • Invalid0.0%0
  • No ROA100.0%9

Propagation

  • Globally propagated90% of full-feed peers or more55.6%5
  • Partially propagated40% to 90%11.1%1
  • Seen by few peersUnder 40%33.3%3

Prefix sizes

IPv4 — 8 prefixes

IPv6 — 1 prefixes

  • /324.3B × /64100.0%1

Recent changes

Announcements that started or stopped since 15th Oct 2026.

  • Announced187.1.177.0/2411th Nov 2026
  • Withdrawn168.227.200.0/239th Nov 2026
  • Withdrawn168.227.202.0/239th Nov 2026
  • Withdrawn186.249.224.0/219th Nov 2026
  • Withdrawn186.249.232.0/219th Nov 2026
  • Withdrawn187.1.184.0/219th Nov 2026
  • Withdrawn187.1.191.0/249th Nov 2026
  • Withdrawn200.169.1.0/249th Nov 2026
  • Withdrawn200.169.2.0/249th Nov 2026
  • Withdrawn200.169.3.0/249th Nov 2026
  • Withdrawn200.169.4.0/229th Nov 2026
  • Withdrawn200.169.6.0/249th Nov 2026

39 announced and 37 withdrawn in all; the most recent are shown.

Routing data derived from RouteViews MRT archives, BGPKIT relationship inference and public registry data.