SKIP, NFS, SSL, etc.

NFS is not a valid example of a one-vendor internetworking protocol. In the early days of NFS Sun worked amazingly hard to get all the major Unix players to support it. They all but lent out engineering staff; they hosted several 'connectathons', where everyone tested interoperability, made the license minimal cost (if not free), etc. And, of course, there was nothing competing. /r$