Claro Brasil IP Ranges
Claro Brasil announces its cable broadband address space under AS28573. The registry of record is LACNIC, which delegates Brazilian resources to NIC.br, and the RDAP record served from registro.br registers the ASN to Claro NXT Telecomunicacoes Ltda, CNPJ 66.970.229/0001-67, registered on 27 November 2003. The operator's own PeeringDB entry describes the same network as Claro S.A. with NET as a qualifier and NET/VIRTUA as the trading name, which is the brand a reader actually meets in the reverse DNS.
- Provider
- Claro Brasil
- Primary ASN
- AS28573
- Category
- ISP
- Headquarters
- Sao Paulo, Brazil
- Announced IPv4 prefixes
- 1885
- Registry
- LACNIC
Known IP ranges
These prefixes are currently announced to the global routing table by AS28573 (AS28573 - Claro NXT Telecomunicacoes Ltda). Prefix sets change over time - use WHOIS Lookup for the authoritative record on any specific address.
179.136.0.0/14
179.140.0.0/15
179.142.0.0/15
179.209.0.0/16
189.60.0.0/16
177.142.0.0/16
179.210.0.0/16
177.32.0.0/16
186.204.0.0/16
189.122.0.0/16
2804:14d:5e00::/40
2804:14d:600::/40
2804:14c:7b00::/40 (IPv6)
What does a Claro Brasil IP mean in a privacy test?
A Claro Brasil address is a Brazilian access line, and the first thing to check is whether it has a reverse name at all, because AS28573 splits cleanly in two. Where a name exists it is eight hexadecimal digits under virtua.com.br, so 179.209.10.20 comes back as b3d10a14.virtua.com.br: read the digits in pairs as bytes and b3 is 179, d1 is 209, 0a is 10 and 14 is 20, which means the hostname is the address written a second time, with no city, no headend and no line type in it. Where a name does not exist it is because NIC.br records no reverse delegation for the block, and 179.136.0.0/14, the largest prefix this ASN announces, has none at all. So a virtua.com.br name confirms you are inside the cable delegation and nothing more, and its absence is a fact about the block rather than about the customer. AS28573 is also only part of Claro: AS4230 is registered separately to CLARO S.A. and routes abuse to Embratel's security group, so a Brazilian address that is not on AS28573 has not been ruled out as Claro.
Where the authoritative Claro record actually lives
A LACNIC lookup for this network does not stay at LACNIC. A request to rdap.lacnic.net/rdap/autnum/28573 answers 307 and redirects to rdap.registro.br/autnum/28573, because Brazilian delegations are administered by NIC.br, and the record you get back is theirs. It gives the registrant as Claro NXT Telecomunicacoes Ltda with the company number published as a typed identifier, CNPJ 66.970.229/0001-67, an abuse contact of virtua@virtua.com.br registered to Virtua's security group, and an administrative contact at engenharia.virtua@claro.com.br. The same redirect applies to address queries.
The NIC.br record then adds two things a plain RDAP object does not. It states the origin ASN on the address object itself, so the block covering 179.209.10.20 comes back as 179.208.0.0/14, allocated on 14 March 2013 and tagged to AS28573; and it lists reverse delegations as first-class entries in sub-ranges rather than one per allocation, so that same /14 shows a delegation for 179.208.0.0 - 179.209.255.255 and a separate one for 179.210.0.0 - 179.210.255.255, both pointed at ns7.virtua.com.br and ns8.virtua.com.br, and both unsigned. Beyond that nothing is published: no geofeed on the RDAP records, and an empty IRR as-set field in PeeringDB, so there is no as-set to filter on and no operator statement of where any block is used. If you need to place a Claro Brasil address in a city, nothing the operator publishes will do it.
Cable subscriber, or a block with no delegation
The hexadecimal name is applied uniformly wherever the Virtua delegation reaches, so on its own it cannot separate a subscriber from anything else. The edge of that delegation is the informative part. Ten addresses were sampled across this network for this page: seven answered with the eight-digit form, in blocks as far apart as 177.32, 186.204 and 189.122, and three returned nothing, all three in the 179.136 to 179.143 range. The NIC.br record for 179.136.0.0/14 explains it: the allocation exists, is tagged to AS28573 and was registered in June 2013, and it carries zero reverse delegations. An address there is still Claro; it simply has no name to give you.
For what an inbound connection means, PeeringDB is the honest summary. AS28573 registers itself as a cable, DSL and ISP network of regional scope, selective peering, and a traffic ratio of heavy inbound, which is an access network pulling traffic toward subscribers rather than a place anybody rents a server. A session opened from this ASN is somebody's own equipment behind a cable modem, and the destination for a complaint about it is the registered Virtua abuse address rather than Claro's general contact. Keep the names straight while you do it: the legal entity on the registry record, Claro NXT Telecomunicacoes, is not the name the network trades under, and PeeringDB and the reverse DNS both say NET and Virtua for the same address space.
Related tools
Frequently asked questions
What does a virtua.com.br hostname mean?
It is Claro Brasil's cable broadband reverse DNS, and the label is the IP address encoded in hexadecimal. Split the eight digits into four pairs and convert each pair to decimal: b3d10a14.virtua.com.br decodes to 179.209.10.20. The name carries no location and no customer information, only the address itself.
Why does a Claro Brasil address have no reverse DNS at all?
Because the block it sits in has no reverse delegation registered. The NIC.br record for 179.136.0.0/14, the largest prefix AS28573 announces, lists zero reverse delegations, and three addresses sampled in the 179.136 to 179.143 range returned nothing. That is a property of the allocation, not a sign that the address is unused or that the lookup failed.
Who is Claro NXT Telecomunicacoes?
It is the legal entity recorded as the registrant of AS28573 in the NIC.br RDAP record, with CNPJ 66.970.229/0001-67. The same network is listed in PeeringDB under the Claro name with NET and VIRTUA as its trading names, so the registry entity and the consumer brand differ on this ASN.
Does Claro Brasil use more than one autonomous system?
Yes. AS4230 is registered separately to CLARO S.A., with a registration date of 16 November 1999 and an abuse contact belonging to Embratel's internet security group, distinct from AS28573 and its 2003 registration and its Virtua abuse contact. A Brazilian address that does not look up as AS28573 has therefore not been ruled out as Claro.
Where do I look up a Claro Brasil IP address?
Start at LACNIC and expect to be redirected. A request to rdap.lacnic.net for a Brazilian resource answers 307 and points at rdap.registro.br, where NIC.br serves the authoritative record. That record gives the registrant, the company number, the allocation dates, the origin ASN on the address object, the reverse delegations and the abuse contact.