https://www.openprovider.com/glossary/dnsbl-dns-blacklist
What Is Dnsbl (Dns Blacklist) - OpenProvider.com - OpenProvider.com
DNSBL, or Domain Name System Blacklist, is a list of domain names that are known to be sources of spam or malicious activity.
what isdns blacklistdnsblopenprovider
https://www.phpclasses.org/package/6874-PHP-Check-if-a-given-address-is-in-a-DNS-blacklist.html
URI Reputation: Check if a given address is in a DNS blacklist - PHP Classes
This class can check if a given address is in a DNS blacklist. It takes an URL as parameter, extracts the URL domain, resolves its IP address and send a...