AS11993 BANCO DO BRASIL S.A.

AS11993 is held by Banco do Brasil S.A., the state-controlled Brazilian bank. This is a corporate network belonging to a single very large enterprise, not a service provider.

What it's used for

• Bank infrastructure at national scale: RIS observes 29 IPv4 prefixes carrying about 68,000 addresses, plus four IPv6 prefixes under 2801:8e::, against only seven neighbours. The combination matters. Tens of thousands of addresses with a single-digit neighbour count is an enterprise that buys transit from a few carriers, never a carrier itself.
• The bulk of the space is one contiguous legacy block, 170.66.0.0/16, announced as a /17 plus two /18s and then punched through with a long tail of /24s. That deaggregation pattern is what a large organisation does when it needs traffic engineering across data centres, branches and ATM estates, rather than the scattered multi-RIR inventory of a leased-address operator.

Notable

• Sampled reverse DNS resolves to ns1.labbs.com.br. Labbs is Banco do Brasil's own developer and API platform, so the space carries first-party bank infrastructure, which corroborates the holder rather than complicating it.
• The RDAP registrant lookups for these prefixes failed at collection time. That is a missing answer, not a clearance and not a red flag. The registrant question is simply unverified here, and the routing and rDNS carry the identification instead.

Interesting

• The IPv6 footprint is native LACNIC space (2801:8e::/36 and friends), so the bank runs dual-stack rather than sitting on IPv4 alone.