On 08/02/2011 02:49 AM, James Matthews wrote: Similar name but that's not the same thing - this is part of the OpenSSL project. The module Clemens was asking about is a kernel module that provides arch-specific acceleration for the in-kernel crypto API. It was there as a module in the f15 GA i686 kernel package: $ rpm -qlp /tmp/kernel-2.6.38.6-26.rc1.fc15.i686.rpm|grep aes-i586 /lib/modules/2.6.38.6-26.rc1.fc15.i686/kernel/arch/x86/crypto/aes-i586.ko But the equivalent on x86_64 was a built-in: $ grep AES_X86_64 /boot/config-2.6.38.8-35.fc15.x86_64 CONFIG_CRYPTO_AES_X86_64=y This was changed in an f15 update: * Wed Jun 15 2011 Kyle McMartin <kmcmartin(a)redhat.com&gt; - Build in aesni-intel on i686 for symmetry with 64-bit. So the functionality is still there, it's just not built as a module any more. Regards, Bryn.