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 # 概述
 参考Reference 1，Page 35 - 39
+* The PCLMULQDQ + AES-NI combination for AES-GCM
+  * AES-NI facilitate high performance AES encryption and decryption
+  * PCLMULQDQ            ```64 x 64 -> 128 (carry-less)```
+    * Binary polynomial multiplication; speed up computations in binary fields
+  * Using it for AES-GCM:
+  * To use it for GHASH computations: GF(2^128) multiplication:
+    1.  Compute ```128 x 128 -> 256``` via carry-less multiplication (of 64-bit operands)
+    2.  Reduction: ```256 -> 128 modulo x^128 + x^7 + x^2 + x + 1``` (done efficiently via software)
 
 # 参考
 * [Cryptographic Hardware and Software and useful architectures](https://www.esat.kuleuven.be/cosic/events/ecrypt-net-school-2018/wp-content/uploads/sites/23/2018/10/kos-school-gueron-2.pdf)