Scott Kitterman writes: > TPA requires cooperation from originators and receivers, so there's > no "new" issue. Any make a list approach that needs both > originators and receivers to participate needs to work for both > large/small originators/receivers and I don't think this does.
"Sez you", but I don't see a rationale for "not work" that actually addresses the intended use case. In fact, what's required for making a list is Mediators (mailing lists) that use the List-Post field. A very large proportion of those that allow open (or subscriber) posting do provide that already, and at least for Mailman lists it's trivial to turn them on. So only the Author Domain (and perhaps its users) need participate to make the list. To use the list, the Author Domain needs to produce "delegation signatures", and recipients need to process those signatures. Implementation is hardly high cost. Large domains can generally afford the cost of revising their custom MTAs. Many small domains will be using Exim, Sendmail, or Postfix, and the latter two implement the milter protocol so a software upgrade isn't necessary, and Exim can be configured to call out to another program, too, so it might need a separate implementation, but it would be do-able without upgrading the MTA. A gradual rollout therefore is quite feasible. _______________________________________________ dmarc mailing list dmarc@ietf.org https://www.ietf.org/mailman/listinfo/dmarc
