Aim of the presented work has been the development of an algorithm for a non-invasive, portable, easy to use, and affordable device for measuring systemic cardiovascular parameters like cardiac output and peripheral resistance. The data acquisition is based on a common oscillometric measurement using an occlusive blood pressure cuff and no additional calibration is necessary. The introduced novel algorithm combines several simulation techniques like neural networks or differential equations, which will be explained briefly. Finally we present some results that justify our approach. This kind of model needs no additional external parameters to work and opens therefore good perspectives for non-expert use.