Distributed Checksum Clearinghouse

As Distributed Checksum Clearinghouse or DCC, a system for detecting spam e -mails is called.

It works on clients and servers that collect the checksums of emails. Clients can also be an SMTP server, for example, the home PC with a spam filter program. The clients initiate the checksum to a ( public ) DCC server. The checksum identifies an e -mail and clearly based on the number of times that this email has been received, other clients that retrieve information from a DCC server, identify an email as spam and filtered out, if necessary.

A special feature of the checksum is that it also applies to an e -mail, if small parts have changed this.


The client to DCC may be used free unless filtering services are offered for users not own and is itself contributed to the DCC network. Alternatively, a commercial version is also available.

Spam filter software with DCC support

Public DCC server

  • Dcc1.dcc - servers.net
  • Dcc2.dcc - servers.net
  • Dcc3.dcc - servers.net
  • Dcc4.dcc - servers.net
  • Dcc5.dcc - servers.net
  • Rzsun01.uni -trier.de
  • Dcc.etherboy.com
  • Dcc1.umr.edu