Distributed Checksum Clearinghouse. A system that tries to identify bulk mail, so that people can reject bulk mail from unknown sources. Bubblegum proxypot can submit messages to a DCC server, which provides DCC users with more raw information to help them decide what messages should be rejected.
Distributed Checksum Clearinghouse is a system of thousands of clients and more than 250 servers collecting and counting checksums related to more than 150 million mail messages on week days. The counts can be used by SMTP servers and mail user agents to detect and reject or filter spam or unsolicited bulk mail.
Distributed Checksum Clearing service which provides checksums for known SPAM emails