Long processing time of AEAD EAX.

[Al Bundy]

I have used aes_all_cli example to test computation time for AEAD EAX/GCM/CCM. I have shortened the plain text to 16 bytes, added pin toggling on encryption function enter and exit to measure processing time on pca10040 board. I got the following results:

EAX => ~95 ms

GCM  => ~250 us

CCM => ~175 us

Is it normal that EAX computation on nRF52832 takes so long in comparison with GCM and CCM?

[Jakub Rzeszutko]

Hi,

EAX is SW library provided by Cifra and it is significantly slower than GCM and CCM and we cannot do much about it. The only way to make it faster is to compile application without debug options.