A serious case can be made that the 7 layer model did more
harm than good by helping the congenitally or willfully clue
challenged pretend to be knowlegable and authoritative.
Without the simplistic view of networking required by the 7
layer model, the experts might have been forced to find other
areas to plow.
I concur. The 7 layer model had its most harmful impact where it is most used,
which is in education. By the late 80's, a pretty standard curriculum was to
have a 7 session networking course, with one session per layer. This was quite
convenient for the naïve teaching assistant who had a general computer science
background but no specialisation in networking. It was also quite wrong, since
it manufactured generations of students who believed that the OSI layering was
somehow logical, when in fact it was the result of accomodating diverse
pre-existing systems, such as X.25 or teletext.
The basic failure was to "teach the standards" rather than "teach the
technology." If you teach the technology, then you deal with algorithms and
scaling issues, and there is plenty to teach and learn: retransmission
algorithms and the use of timers, various approaches to congestion control,
name resolution, resource allocation algorithms, marshalling and
un-marshalling, synchronization and time, and many more. If you teach the
standard, then you content yourself with whatever a committee picked. Worse
still, in many case the committees' decisions were grounded in political
compromise and cloaked in technicalities. In many cases, the students got such
a distorted view that you litteraly need to make them "unlearn OSI" before they
can do productive networking work.
-- Christian Huitema