[e2e] Re: [Tsvwg] Really End-to-end or CRC vs everything else?

[Melinda Shore]

>From: David P. Reed <dpreed at reed.com>
>To: Craig Partridge <craig at aland.bbn.com>
>Cc: Dennis Ferguson <dennis at juniper.net>; Michael A. Ramalho <mramalho at cisco.com>; <tsvwg at ietf.org>; end2end
<end2end-interest at postel.org>
>Sent: Monday, June 11, 2001 1:00 PM
>Subject: Re: [e2e] Re: [Tsvwg] Really End-to-end or CRC vs everything else?


> In addition, it has become clear over the last few years that there is a
> rising propensity for introduction of middleboxes/services that try to do
> favors that supposedly don't "change the semantics" of the communication
> among applications.  The "radical" part of my position is that end-to-end
> protocols should be able to detect and reject these "favors".  That still
> leaves a lot of room for network optimizations - lossless compression,
> dynamic routing, congestion control, etc. all can be done without tinkering
> with the application messages.

I'm going to assume that by "application messages" you mean
"anything after the transport header."  Anyway, to some extent
it's already the case that there's an implicit rejection
mechanism, in that some things already fail when certain kinds
of middleboxes are introduced (firewalls break session-oriented
protocols, NATs break integrity protection).  Operators often
don't want to make network topology known to applications, and
it's difficult to find agreement, in practice, that transport-
layer middleboxes should be detectable by applications.

Melinda