Distributed Checksum Clearinghouse
The following section describes the Distributed Checksum Clearinghouse (DCC). More information is available at http://www.rhyolite.com/anti-spam/dcc/.
DCC is a system for identifying bulk email messages. It is made up of a distributed collection of servers, where counts of email messages received by clients are maintained. Each participating client computes checksums for each email it receives and sends them to a DCC server, which in turn floods this information to other participating servers. It should be emphasized that messages are never forwarded to the DCC servers, only the checksums.
The server can be set up to tag messages with a header indicating the DCC scores or to reject messages on ...