As a result of his contributions, South Korea became the second country in the world to have the IPv4 network (the Internet), after the United States. Born in [Japan], in 1943.

He worked as a computer system designer at Rockwell International and a member of technical staff at the Jet Propulsion Laboratory until 1979.

In May 1982, he helped develop IPv4 network (the internet) between Seoul National University and the Korea Institute of Electronics Technology.

[1] As a result, South Korea became the second country in the world to be largely connected to the Internet, after the United States,[citation needed] and he is called "the father of Korean Internet".

He was a professor at Keio University's Shonan Fujisawa campus in their policy and media research department. His research fields include the Internet, systems engineering, and human-computer interactions.