He was involved in pre-standards work for X.400/X.500 in the International Federation for Information Processing (IFIP) WG 6.5, and post-standards profiling in the National Institute of Standards and Technology OIW.
He was a co-founder (1994) and Chief Visionary Officer of First Virtual Holdings, called "the first cyberbank" by the Smithsonian Institution,[citation needed] that launched an Internet Payment System in October 1994.
In 1997 Stefferud, Brian K. Reid and Richard J. Sexton formed the Open Root Server Confederation as a potential organization to serve as an institutional version of John Postel's IANA, and a proposal was submitted[3] to the US Government Department of Commerce NTIA, which eventually picked the joint Network Solutions/IANA proposal that became ICANN.
Together with Ed Gerck, Stefferud was the co-founder (2001) of Network Manifold Associates Inc.,[5] working on the development of "target-free" technologies for secure Internet communications.
Stefferud was also chairman of the NMA Advisory Board and was involved in the creation of "instant on" security products ZSentry and Zmail.