First, you should always protect against your machine — the one serving your Web content to millions of users — from being used as a mail relay.

首先，应当始终防止您的机器(为数百万个用户提供Web内容的机器)成为一个邮件中转站。

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There are experts in the different areas who are available to ask in Internet Relay Chat (IRC) or, if necessary, via e-mail.

可以通过 Internet 中继聊天（Internet Relay Chat，IRC）（或者在必要的情况下通过电子邮件）询问不同领域的专家。

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Server relay allows server to relay mails to a specific mail server instead of saving or sending mails directly.

依设定转寄到特定伺服器去，让下一个伺服器代做原本该寄信或存信的工作。

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Back then many companies ran a free, open-source e-mail relay technology but ended up spending more than they thought they would making the stuff work.

FORBES: You Get What You Pay For

Some use "mail relay, " borrowing someone else's domain to send e-mail.

FORBES: Spam Warfare

Back in the early 80s a man by the name of Geoff Goodfellow had an idea: to relay electronic mail from Arpanet to his alphanumeric pager.

ENGADGET: Geoff Goodfellow, early inventor of wireless email, profiled