----- Original Message -----
From: "Masataka Ohta" <mohta@necom830.hpcl.titech.ac.jp>
To: "Michel Py" <michel@arneill-py.sacramento.ca.us>
Cc: "Bill Cunningham" <billcu@CITYNET.NET>; "Robert Elz"
<kre@munnari.OZ.AU>; <ietf@ietf.org>
Sent: Friday, October 04, 2002 5:20 PM
Subject: Re: TCP/IP Terms
> Michel;
>
> > In terms of design, if you do TCP/IP *only* design, the TCP/IP model is
> > probably enough. However, the Internet is not only TCP/IP. Carriers, for
> > example, don't care much if their fiber transports TCP/IP or IPX or
> > voice or video or GigE.
>
> No.
>
> Anything at or above transport layer is a layer internal to end
> systems and has nothing to do with networking or network protocols.
>
> Seperation of transport and application layers is a overkill
> for a best effort network, though it may help standardize the
> internal design of end systems such that anything supported by
> kernel belong the transport layer. You can check the reality
> that application and transport areas of IETF are now almost
> identical, though, historically, trasnsport area was working
> on protocols likely to be implemented in kernel.
>
> In addition, defining a thin transport layer may be useful over a
> hypothetical port-number-aware network such as that supporting RSVP.
>
> However, forcibly defining a session-layer-aware network is a
> layer violation.
>
> > And, there are complex multi-protocol networks that a) don't use only
> > TCP/IP and b) would not be able to use the TCP/IP model anyway because
> > it's too simple.
>
* Would not be able to use TCP/IP.*
How can that be changed?
> Unless you are trying to standardize internal design of application
> layer gateways, which is like defining standardizing the way of
> structured programming and is hopeless, the separation of upper
> layers is meaningles.
>
> > The bottom line is: lots of people are going to continue using the OSI
> > model. We don't need two different models.
>
> I am having no difficulty in teaching my students, even though I often
> forget the names of two OSI layers between transport and application.
> In writing this mail, I only remember one: session.
>
> New comers don't need two different models.
>
> Masataka Ohta
>