Wanted: ISO level 4

[Doug McCallum]

> "ISO level 4 (the transport level)" is an abstraction.
> It can be realized in different ways, and has been on systems
> such as 4.2BSD.  You need to find out just what your friend is
> really after.

ISO level 4 (NBS/ISO TP4) is also a real protocol that is very close to
being an international standard.  It is currently in DIS (Draft International
Standard) form (ISO/DIS 8072 for the Transport service definition and
ISO/DIS 8073 for the Connection oriented transport protocol specification).
This is the protocol that was used at the NCC network demo.  All 7 layers of
the ISO Reference Model will have ISO protocols defined for them.  Currently,
Network is fairly stable but still a DP (Draft Proposal), Transport is being
finalized, Session is in DIS form.  The higher layers are in varying states
depending on the application intended.  Presentation is a ways from completion.

There has also been some talk that the National Academy of Science is completing
a study that will recommend that DoD adopt the ISO Class 4 protocol.  NATO has
already said they will adopt it.  It will be interesting to see what happens
over the next few years.

			Doug McCallum
			{allegra, btlunix, ucbvax, hao}!nbires!mccallum