Into generating True Random Numbers - a practical approach using FPGA

True Random Numbers represents a sensitive research area for cryptographic algorithms and applications. They are mostly used in generating non-reproducible and non-deterministic patterns used in different cryptographic protocols. A True Random Number Generator basically consists of three main components: a noise generator, that is based on a physical incontrollable phenomenon, a randomness extractor (for assuring that the generated bits are uniformly distributed), and a randomness testing battery. Over the last years, since the hardware technologies evolved, the random number generation became (once more) an attractive research field, channeling a lot of efforts from the research communities worldwide. As a consequence, the True Random Number Generation process became more detailed and was elaborated in international standards (for example the NIST -National Institute of Standards and Technology- standard). This paper presents some novel practical approaches on True Random Number Generation, and some personal deviations of some classical approaches, using the most common noise generator, based on oscillators jitter, used in different contexts and variations, implemented in FPGA logic. Moreover, the paper describes the whole generation process, presenting, in comparison, the testing results of the generators shown in the paper.