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# SSL / Encryption App

SSL (HTTPS) and file encryption/decryption can be offloaded to a processor’s AES-NI extension. This can both speed up these operations while lowering processing overhead. This requires a processor with the AES-NI instruction set.

Here are some examples how to check if your CPU / environment supports the AES-NI extension:

- For each CPU core present: `grep flags /proc/cpuinfo` or as a summary for all cores: `grep -m 1 ^flags /proc/cpuinfo` If the result contains any `aes`, the extension is present.

- Search eg. on the Intel web if the processor used supports the extension Intel Processor Feature Filter You may set a filter by `"AES New Instructions"` to get a reduced result set.
- For versions of openssl >= 1.0.1, AES-NI does not work via an engine and will not show up in the `openssl engine` command. It is active by default on the supported hardware. You can check the openssl version via `openssl version -a`
- If your processor supports AES-NI but it does not show up eg via grep or coreinfo, it is maybe disabled in the BIOS.
- If your environment runs virtualized, check the virtualization vendor for support.

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