PORTABLE ELLIPTIC CURVE CRYPTOGRAPHY FOR MEDIUM-SIZED EMBEDDED SYSTEMS

Abstract

In general, cryptographic methods are very intensive on memory and computing power. The reason for this are the mathematical operations necessary on really big numbers. While these operations do not pose any major issues on the latest consumer personal computer, embedded systems often only have a fraction of this raw power available. The goal of this thesis is to come up with a way for these devices to communicate with other such devices in a secure way, that is, with all the communication of data between these devices encrypted.

From the beginning, Elliptic Curve Cryptography (ECC) has been the most favoured method to achieve this goal. ECC promises the same level of security for smaller key sizes (and thus smaller numbers), but the trade-off is the increase in mathematical complexity. Through optimisation and careful selection of algorithms, this form of cryptography has become feasible for embedded systems as well.

The research in this thesis is focused on the development and implementation of an elliptic curve based cryptographic system for embedded devices which can provide digital signatures, key generation/storage and encryption/decryption of data. The main aspects to achieve this goal are the selection and implementation of a suitable elliptic curve, a fast cryptographic hash function and a strong block cypher.