Body Checksum Calculation

Vernon Schryver
Mon Apr 1 17:16:54 UTC 2002

> From: Phil White <>

> DCC relies on the ability to recognise certain emails as bulk. However, it is 
> inevitable that some will sneak through. If I set up a dedicated email 
> address for other users to forward all email they regard as spam, will dcc 
> still calculate the checksums correctly?

If not, it's a bug.

If the question is about creating spam traps, see 

  - the last example in the dccproc man page in either the DCC source

  - the discussion of spam traps in the DCC installation instructions
      in the DCC source or in

>                                          How many MUAs are known to reformat 
> messages, add line prefixes, headers, etc and will this break the dcc 
> mechanism?

No, because adding line prefixes is likely to change the "Body"
checksum, but usually not the "Fuz1" and "Fuz2" checksums.
All three of those checksums ignore whitespace.

> What methods do others here use?

The list of spam dictionary attack names can be used as spam traps
as mentioned on

It is also possible to put spam traps on web pages and catch some
spam.  For example, look for aswwwblock in the source HTML for 

Vernon Schryver

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