Open Mail Relay

An open mail relay is an SMTP server configured in such a way that it allows anyone on the Internet to send e-mail through it, not just mail destined to or originating from known users. This used to be the default configuration in many mail servers; indeed, it was the way the Internet was initially set up, but open mail relays have become unpopular due to their exploitation by spammers and worms. Many relays were closed, or were placed on blacklists by other servers.

Read more about Open Mail Relay:  History and Technology, Abuse By Spammers, Anti-spam Efforts, Modern-day Proponents, Closing Relays

Famous quotes containing the words open and/or mail:

    It’s fairly obvious that American education is a cultural flop. Americans are not a well-educated people culturally, and their vocational education often has to be learned all over again after they leave school and college. On the other hand, they have open quick minds and if their education has little sharp positive value, it has not the stultifying effects of a more rigid training.
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    The mail from Tunis, probably,
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