Re: A modest supposition

At 17.28 -0800 0-01-25, hardie@equinix.com wrote:
> Constant efforts to achieve efficiency by collapsing lower layers
> (e.g. POS's replacement of ATM) are and forever will be balanced by
> the constant reinvention of those lower layers at the application
> layer.
>
> more specifically,
>
> Every messaging protocol expands until it replicates the control
> mechanisms of TCP.

People who are expert on one layer, do not know enough about
services in other layers, so they repeat them in their own
layer. It is not only transmission control, also security
and encryption is often repeated in multiple layers on top
of each other.

There are even layers on top of each other doing the same
thing within the application layer.

Example: If you send HTML in e-mail, non-7-bit-characters
can either be encoded by the HTML sublayer (ä to ä,
as an example) or by the MIME layer on top of the HTML
sublayer (ä to =E4) using quoted-printable encoding.
So MIME and HTML do the similar task of special-koding
non-7-bit-characters twice on top of each other.

Experienced users know that in plain text, the HTML
encoding works better, but in parameters of various
kinds, MIME encoding sometimes works better.
------------------------------------------------------------------------
Jacob Palme <jpalme@dsv.su.se> (Stockholm University and KTH)
for more info see URL: http://www.dsv.su.se/jpalme/

Received on Tuesday, 25 January 2000 22:13:04 UTC