First direct implementation of a true random source on programmable hardware

True random sources are not implementable in digital hardware, so that many practical applications have historically relied on pseudo-random generators in order to avoid the potentially long prototyping times and the costs of dedicated analog design. However, pseudo-random sources have liabilities that make them hardly suitable for some tasks (notably security related ones). Previous attempts to conciliate security, cost-effectiveness, and rapid development included the exploitation of the analog accessory parts often present on programmable devices. In these designs some analog blocks are used for their side effects (noise amplification) rather than for their originally intended behaviour. Conversely, here we report a direct implementation of a true random source on programmable, low-cost, general-purpose hardware, where all blocks are used only for their nominal function. To the best of the authors' knowledge, this is the first proposal of this sort. The design exploits an FPAA, and is based on a non-linear system exhibiting chaotic behaviour. Measures confirm the correct operation, high throughput, and robustness of the system. Copyright © 2005 John Wiley & Sons, Ltd.