By 1984, over 180 university, industrial, and government computer science departments were participating in CSNET. His team also developed one of the first Internet protocol implementations (1981-84, IBM VM systems).
Dr. Landweber was a leader in the development of the international Internet. In the 1980s, he helped establish the first network gateways between the US and countries in Europe, Asia and Latin America. Landweber promoted CSNET through the International Academic NetWorkshops (IANW/INET or “Landweber Conferences”), which educated scientists from around the world on how to implement national academic and research networks in their countries. These NetWorkshops, which were attended by individuals who were pioneering the development of national networks in their countries, helped accelerate the development of the Internet.