Abstract
With a fast development of network communication, the application of IC smart card becomes more and more frequent. Since many personalized data are stored in the chip of IC smart card, the capability of high data security is an important issue of IC smart card. Therefore, a word-based RSA crypto-processor for IC smart card is proposed. Due to the lower cost issue on smart card, an RSA crypto-processor core with small area is essential. In order to reduce silicon area, the word-based architecture is attached to RSA crypto-processor core. Using word-based architecture, the different key length can be implemented by appropriately controlling the iteration of loop. This feacture provides the flexibility between security and computation time for user. Since our RSA crypto-processor core is based on Montgomery's algorithm, the final reduction will decrease the speed. Therefore, we modify word-based Mongomery's algorithm to eliminate this problem. Moreover, instead of using software, we design hardware to generate modular multiplicative inverse N0' . The resulting 16-bit word-based RSA crypto-processor core, which is synthesized by 0.35um cell library, can output 1024 bits encrypted/decrypted data in 51ms at the operating frequency is 125 MHZ. Finally, we applied 16-bit word-based RSA crypto-processor core to asymmetric crypto processor (ACP). Based on TSMC 0.35um 1P4M technology, an ACP chip is implemented.