Enterprise Replication must connect to each of the servers directly to process the master schema verification and optional table creation.

Enterprise Replication必须直接连接到每个服务器，以处理主模式检验和可选的表创建。

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Google jumped on board quickly, rolling out optional 2-step verification for its users.

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The "two-factor" verification system, which will be optional, asks users to register a phone number, e-mail account and six-digit code that would have to be entered, via text message, each time they log in to the site.

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