Authentication is the mechanism whereby systems may securely identify their users. Authentication systems provide an answers to the questions.

系统可以通过认证这种机制来安全的识别它们的用户。

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Database: the database performs both identification and authentication of users.

数据库：数据库执行对用户的识别和身份验证。

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The base authentication allows users to carry out basic tasks like viewing previous transactions.

基本身份验证允许用户执行基本任务，比如查看以前的事务。

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Luckily, users with the new two-factor authentication feature enabled would seem to be immune to the attack.

FORBES: Enable Two-Factor Authentication On Your Apple Account To Avoid A New Password-Resetting Attack

On Facebook, for example, two-factor authentication is triggered when users try to log in in an unexpected way, such as from a computer in a different country.

BBC: Technology

Publishers must do their own authentication of users and their own e-commerce outside the Apple interface, to make the program work.

FORBES: Will Apple Force More Publishers to Build Paywalls?