Advanced Encryption Standard Instruction Set (or the Intel Advanced Encryption Standard New Instructions; AES-NI) is an extension to the x86 instruction set architecture for microprocessors from Intel and AMD proposed by Intel in March 2008. The purpose of the instruction set is to improve the speed of applications performing encryption and decryption using the Advanced Encryption Standard (AES).
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Intel and AMD x86 architecture
The following processors support the AES-NI instruction set:
Hardware acceleration in other architectures
AES support with unprivileged processor instructions is also available in the latest SPARC processors (T3, T4, T5, M5, and forward) and in latest ARM processors. The SPARC T4 processor, introduced in 2011, has user-level instructions implementing AES rounds. These instructions are in addition to higher level encryption commands. The ARMv8-A processor architecture, announced in 2011, including the ARM Cortex-A53 and A57 (but not previous v7 processors like the Cortex A5, 7, 8, 9, 11, 15) also have user-level instructions which implement AES rounds. In August 2012, IBM announced that the forthcoming Power7+ architecture would have AES support. The commands in these architectures are not directly compatible with the AES-NI commands, but implement similar functionality.
IBM z9 or later mainframe processors support AES as single-opcode (KM, KMC) AES ECB/CBC instructions via IBM's CryptoExpress hardware These single-instruction AES versions are therefore easier to use than Intel NI ones, but may not be extended to implement other algorithms based on AES round functions (such as the Whirlpool hash function).
Supporting x86 CPUs
VIA x86 CPUs, AMD Geode, and Marvell Kirkwood (ARM, mv_cesa in Linux) use driver-based accelerated AES handling instead. (see Crypto API (Linux))
The following chips, while supporting AES hardware acceleration, do not support the AES-NI instruction set:
ARM architecture
Other architectures
Performance
In AES-NI Performance Analyzed, Patrick Schmid and Achim Roos found, "... impressive results from a handful of applications already optimized to take advantage of Intel's AES-NI capability". A performance analysis using the Crypto++ security library showed an increase in throughput from approximately 28.0 cycles per byte to 3.5 cycles per byte with AES/GCM versus a Pentium 4 with no acceleration.
Supporting software
Most modern compilers can emit AES instructions.
Much security and cryptography software supports the AES instruction set, including the following core infrastructure: