I'm currently revising for my third year exams and came across the following
question (from a past paper):

The major advantages with the layered approach to network protocols (eg. the OSI
model) include modularity and manageability. List at least two major
disadvantages of such an approach. Explain your answer.

Any suggestions? All I can think of is performance loss... Which I don't think
is a major issue. I suppose it can be difficult to decide where to put things.
For example IPsec, network layer (therefore transparent) vs. higher layers
(better protection*).


Cheers,

Ben



* Assuming it is used correctly... (End-to-end cryptography in the hands of the
user is more secure than network layer protection [assuming user's can manage
it...])