cancilla on "Activating VaultPress"

I signed up for VaultPress through the Jetpack plugin, but VaultPress is asking me to install an additional plugin. The VaultPress plugin isn't found when I search WordPress plugins through my blog, so I'm wary of installing it. Is there a way to activate my new VaultPress subscription through Jetpack, or do I really have to load an additional plugin? I thought VaultPress was part of Jetpack? Thanks for helping me clear up my confusion.
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