SecureAPT

In recent releases, Debian has been using strong crypto to validate downloaded packages. This is commonly called "secure apt" (or "apt-secure") and was implemented in Apt version 0.6 in 2003, which Debian migrated to in 2005. Since the documentation (here and here) is fairly slim on how this all works from an administrator's point of view, this document will try to explain in detail how secure apt works and how to use it. 

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