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:
“Through open doors, the dining-room declares
A larger loneliness of knives and glass
And silence laid like carpet.”
—Philip Larkin (1922–1986)
“The mail from Tunis, probably,
An easy Morning’s Ride—”
—Emily Dickinson (1830–1886)