AS10515 CLT-NIC

CLT-NIC is registered to Verisign Infrastructure & Operations. Unusually for a famous name, the routing here backs the label up: the announced space carries Verisign's own authoritative DNS servers rather than an office network.

What it's used for

The inventory is small and specific. The AS announces 4 IPv4 prefixes totalling 1,024 addresses (four /24s) and 4 IPv6 /48s, with a single observed neighbour in RIS. Addresses inside these prefixes are the published nstld.com nameservers Verisign operates as a registry and DNS provider: 192.42.173.0/24 and 192.42.177.0/24 hold nstld.com server addresses, and 2001:500:120::/48 and 2001:500:124::/48 hold their IPv6 counterparts.

That explains the otherwise odd shape. A thousand addresses is nothing, but each /24 exists to carry a nameserver address that must be announced as its own route, which is standard practice for authoritative DNS so that a server's prefix can be routed and withdrawn independently of everything else. The value of this AS is in what those few addresses answer, not in how many there are.

Notable

Do not confuse this with the root server or gtld-servers.net networks, which Verisign also runs but from different autonomous systems. The prefixes here come from more than one registry's ranges, which is normal for an operator with globally distributed DNS nodes and says nothing reliable about geography.

Reverse DNS returned nothing on the eight addresses sampled. That is a sample, not a finding, and no conclusion should be drawn from it.