Among other things, he is generally credited with being the first to recognize the optimality and practical importance of the Viterbi algorithm, and his tutorial paper on the subject is widely cited.
[2][3] His work in the Viterbi algorithm and in advancing the understanding of coding theory in general influenced the design of modern digital modems.
He became vice president of research and development at Codex, through its acquisition by Motorola in 1977, serving in both management and technical positions.
[7] In 1998 Forney received a Golden Jubilee Award for Technological Innovation from the IEEE Information Theory Society.
[8] He has also received the 2016 IEEE Medal of Honor for "pioneering contributions to the theory of error-correcting codes and the development of reliable high-speed data communications".