Infrastructure
What is Reverse DNS?
Looking up the hostname registered for an IP address, the opposite of normal DNS, which can reveal the provider or purpose of a server.
Reverse DNS maps an IP address back to a hostname using a PTR record. The owner of the IP block, usually the hosting provider or ISP, controls what it returns.
The hostname can reveal the provider, the region, whether an address is residential or a data centre server, and sometimes the customer's own naming. It is quick enrichment but easy to set to anything, so it is supporting evidence rather than proof.