My question is about performance of JavaCard smart-card on AT90SC25672RCT chip.
The matter is that I want to develop project related to cryptography using JavaCard for educational purposes.
Right now is time to buy smart-card and that's why I wonder if card with this chip will cover my needs. The matter is that I've decided to use some cryptographic protocol that will require some calculations both on desktop and smart-card side.
So my question is addressed to people that have JavaCard now and can tell me if it is possible to run random generator and compute couple of hash values in within sane amount of time or I should use some protocol that requires less calculations?
Recommendations devices or minimal requirements are also welcome.
As already mentioned, smart cards in general have co-processors. Symmetric ones for DES and AES family of algorithms and asymmetric ones for RSA and elliptic curves.
I don't know what you consider a sane amount of time, but generating signatures is never a problem (well below one second), while generating a 4096 bit RSA key pair on the card may last minutes.
The typical bottleneck is the I/O interface, heavily depending on the card and the reader at hand (among others by the external clock). This is the reason, why nobody will sent a document of megabytes to a card, just to get the hash computed, but will hash externally. The small random numbers to be hashed within cryptographic protocols are of course no problem. Cards are getting faster on the I/O side too, but the proven approach will remain with us for some time.