Hector Santos wrote:
In my view, you have an over simplification and Crocker's doc is
attempt to model a more complex integrated world. Its one view abeit
one that attempts to prescribe a model based on STDs and RFCs. I
think it could of been done in a more readable fashion, like a
Requirements/Optional Grid to start work ala RFC 1153
Standard textbook models are much simpler than what I am proposing. The
most popular book (Peterson & Davie, 4th ed.) has just a sequence of
"gateways", and no good explanation as to why so many are needed. The
two reasons given are 1) The recipient does not want to disclose the
actual host on which he reads his email, and 2) The recipient's machine
may not always be running, and a "gateway" can hold the message until it
is ready to be delivered.
What I'm looking for is a model that is almost as simple, but a better
foundation to understanding real systems. We have maybe half a week in
a 3-unit class on Computer Networks, so we clearly can't cover all the
details in email-arch.
I do think, in my opinion, your first illustration is pretty
fundamental and much easier to understand, grasp without reading the
context. IMO, Dave's doc is too overwhelming for MOST people to read
- totally only useful for highly IETF trained geeks.
My primary goal is optimizing the model for students. A secondary goal
is conformity with standards. There is always a tradeoff. If we
simplify too much, students will not learn how real systems work. If we
add too much detail, or use jargon instead of plain English, students
will learn less of the fundamentals that are needed long after passing a
test.
I'm looking for constructive criticism. If you believe the model is
oversimplified, give me an example of an important system that the model
should cover. If you think you can improve on the terminology, give me
some specific alternatives.
The model is still work-in-progress, but the most complete description
is at http://open-mail.org/MHSmodels.html
Best Regards,
************************************************************ *
* David MacQuigg, PhD email: macquigg at ece.arizona.edu * *
* Research Associate phone: USA 520-721-4583 * * *
* ECE Department, University of Arizona * * *
* 9320 East Mikelyn Lane * * *
* http://purl.net/macquigg Tucson, Arizona 85710 *
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