After completing his studies, Oshman worked for several years as an engineer at Philco Corporation, an American company that specialized in electronics and defense systems.
Under Oshman's leadership, ROLM became a major player in the telecommunications industry, particularly in the development of private branch exchange (PBX) systems.
After leaving ROLM, Oshman went on to serve as the CEO of Echelon Corporation, a company that specialized in creating energy-efficient technologies for homes and buildings.
Under his leadership, Echelon became a leading player in the smart grid industry, developing technologies that helped to improve the efficiency and reliability of energy systems.
He was a pioneer in the development of Silicon Valley and played a key role in the growth of several companies that helped to shape the industry.