Mutual Internet
Practices Asssoc.

About Scope

Certified Server Validation*

Certified Server Validation (CSV) provides a mechanism for a mail-receiving server to assess a mail-sending server. In particular, CSV permits a mail-receiving server to determine:

  1. Whether a mail-sending relay host is correctly identifying itself
  2. Whether the operator of the sending host's network has authorized it to operate as a mail relay, using CSA.
  3. Whether independent parties have a good assessment of the quality of that network's mail operation, using DNA. That is, is the operator less-likely or more-likely to be the source of problematic email?





Hello 'Certified Server,' Goodbye Spam, B. Livingston, Datamation, 7 Nov 04


We are maintaining a list of CSV implementations and uses.



  • Certified Server Validation (CSV): html or txt
  • Client SMTP Authentication (CSA): html or txt
  • Domain Name Accreditation (DNA): html or txt


CSV originally stood for "Client SMTP Validation". However, market(ing) feedback suggested that "Certified Server Validation" is more useful to folks who are trying to understand the nature of the service, without requiring that they be email geeks...
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