Born in Vienna, he moved to the New York City where he went to Brooklyn Technical High School, earned a B.S. in mechanical engineering from Cooper Union (1948), an M.A. in physics (1953) and electrical engineering from Columbia University (1960). Sumner joined Bell Labs (1948) where he became leader of the group that developed the pulse code modulation transmission system (1955), later director of transmission systems (1960) that developed the T1 carrier system (1962). Following this, he led the underwater transmission laboratory projects on submarine surveillance systems (1962-67), the transmission media division in Atlanta, Georgia (1967-71) and the loop division (1971-) where he oversaw development of computerized network management systems. After retiring (1989) he served as president of the IEEE (1991) and was chairman of New Jersey Inventor's Hall of Fame. Sumner died of heart failure.
He held eleven patents, was elected to the National Academy of Engineering (1988). Sumner was an IEEE Fellow and receiver of the IEEE Alexander Graham Bell Medal jointly with M. Robert Aaron and John S. Mayo (1978). The IEEE Eric E. Sumner award includes a bronze medal and was instituted in his name (1995).