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- HashCash ( http://hashcash.org/ )
See http://hashcash.org/faq and http://hashcash.org/draft-hashcash.txt.
This is a technological solution, while Bonded Sender is an economic solution and Habeas is a legal solution. Hashcash may not be appropriate for large mailing lists, as it requires substantial computational power to send each email.
- whitelist.cf ( http://www.rulesemporium.com/rules.htm#whitelist )
SARE maintains a family of whitelist.cf rules config files which will apply a USER_IN_WHITELIST score to your newsletter if you qualify. Though these initially apply only to systems which retrieve the custom SARE files, these will feed eventually to the SA distribution set, and the USER_IN_DEF_WHITELIST rule.
To qualify:- Your newsletter needs to be From a consistent and recognizable address.
- Your newsletter needs to be emailed from a reliable and recognizable server, whose domain name can be validated by systems receiving the email, and must pass from that server to the recipient system.
- Your newsletter must be double opt-in / confirmed opt-in, and must not be a subject of spam complaints.
- Your domain must not be a subject of spam complaints.
Other Resources
Where else can you look for guidance?
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