IP Blacklist (IP Blocklist)

An IP blacklist (also referred to as an ip blocklist) is a security registry containing IP addresses that automated threat intelligence feeds, firewalls, or network administrators have identified as sources of abusive, malicious, or excessive traffic. When exploring what is an ip blacklist, consider an automated security gate at a commercial shipping port that cross-references truck license plates against a list of vehicles involved in safety violations. Incoming packets originating from blacklisted addresses are dropped immediately during the TCP handshake or rejected with HTTP 403 Forbidden responses.