The numbers are designated "RSA-XXXX", where XXXX is the number's length, in bits.

此句是否应翻译成：这些数字被设计成“RSA-XXXX”形式，这里的XXXX是以位为单位的数字的长度。

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For the uninitiated, Snapchat is a photo-messaging service that allows you to send photos that will self-destruct after a designated length of time.

FORBES: Why Facebook Needs Its Own 'Snapchat'

The length of beachfront designated for naturism remains the same and will not affect the Heather Walk footpath.

BBC: Studland Nudist Beach granted inland extension