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:
“The republican is the only form of government which is not eternally at open or secret war with the rights of mankind.”
—Thomas Jefferson (1743–1826)
“The mail from Tunis, probably,
An easy Morning’s Ride—”
—Emily Dickinson (1830–1886)