In this essay, I guide the reader through the technologies that led from the copper-based network to the new generation fiber-based technologies and display their abilities. I examine currently available and future PON technologies, and introduce the building pieces of the optical system. The final goal is to enable interwork between VPI Transmission Maker simulation software and AccessPlan, a network design framework developed at TMIT, in order to automatically validate physical layer properties of the designed system. To reach this, first I chose the most promising passive optical network types TDM and WDM, and create their models in VPI. While examining the chosen networks functions, I determine the critical parameters, which are key to the design of TDM- and the WDM-PONs. I study the structure of the files generated by VPI and point out the context of the critical parameters, to help automatic generation of similar files with AccessPlan. From the collected knowledge I design a simple network without the graphical interface, and successfully run on VPI, showing the feasibility of automatic network design.