I would like to find a chip that can do public key encryption/decryption, maybe RSA or DSA. Particularly the key needs to be securely stored on chip. Can anyone suggest some choices?
(Update) Since I am thinking of using it only for authentication and key exchange purpose, speed may not be an issue. Any time less than 1 second per encryption/decryption is acceptable. But security is of a high concern. I would want the key won't be read out no matter how by a normal hacker (who may have access to the device). I am seeing the SHA chip ATSHA204 quite attracting in terms of security features. Is there a similar RSA/DSA counterpart?