His notable past research includes the advancement of digital transmission systems, including contributions that made telephony possible over the existing telephone network, the use of VLSI to realize functions in the telephone network, and VLSI architectures to solve signal processing challenges.
He also contributed to a successor to Blosim called Ptolemy, which is still being actively developed and used.
In 1983, David Messerschmitt was elevated to the grade of Institute of Electrical and Electronics Engineers (IEEE) fellow for contributions to the theory of transmitting digital waveforms on band-limited channels.
[2] In 1999, Messerschmitt received the IEEE Alexander Graham Bell Medal "for fundamental contributions to communications theory and practice, including VLSI for signal processing, and simulation and modeling software".
In 2007, Messerschmitt co-founded the Software business community (SWBC) in cooperation with the Helsinki University of Technology.