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:

    Parents offer an open womb. More than anyone else in your life, mothers, and sometimes fathers, can kiss it, and make it well when their grown children need to regress and repair. More than anyone else in your life, mothers, and sometimes fathers, can catch you when you start to fall. When you are in disgrace, defeat, and despair, home may be the safest place to hide.
    Frank Pittman (20th century)

    Always polite, fastidiously dressed in a linen duster and mask, he used to leave behind facetious rhymes signed “Black Bart, Po—8,” in mail and express boxes after he had finished rifling them.
    —For the State of California, U.S. public relief program (1935-1943)