I am working on a project wherein ECC needs to be implemented on small devices, namely, CC2650 sensor-tags for authentication. The ECC implementation should be on Contiki OS. I have read some articles which suggest it is possible to implement ECC on tiny devices. I want to know is it viable practically considering the memory and CPU processing overhead or one should only use Symmetric encryption, AES on these devices? I would also appreciate if someone can give me feedback on the choice of preferrable library among, RELIC, TinyECC, and OpenSSL.
The CC2650 is a Cortex M3 with 128KB flash memory and 20KB SRAM.
This is definitely not enough for RELIC or OpenSSL.
TinyECC fits, but even if this is only for signatures, some symmetric cryptography will be needed in addition to it.