Re: T is for Transfer

An enthusiastic +1.  Thanks, Scott, I could use a hand. 8-)

> TCP stack. The firewall advantage is silly;
> the first thing the firewall vendors will do once SOAP is finalized is
> distribute the "SOAP stops here" upgrade.

Exactly right.  Roy talks about this in the same section he talks about
HTTP not being a transport protocol;

HTTP is not designed to be a transport protocol. It is a transfer protocol in which the messages reflect the semantics of the Web architecture by performing actions on resources through the transfer and manipulation of representations of those resources. It is possible to achieve a wide range of functionality using this very simple interface, but following the interface is required in order for HTTP semantics to remain visible to intermediaries.

That is why HTTP goes through firewalls. Most of the recently proposed extensions to HTTP, aside from WebDAV [60], have merely used HTTP as a way to move other application protocols through a firewall, which is a fundamentally misguided idea. Not only does it defeat the purpose of having a firewall, but it won't work for the long term because firewall vendors will simply have to perform additional protocol filtering. It therefore makes no sense to do those extensions on top of HTTP, since the only thing HTTP accomplishes in that situation is to add overhead from a legacy syntax. A true application of HTTP maps the protocol user's actions to something that can be expressed using HTTP semantics, thus creating a network-based API to services which can be understood by agents and intermediaries without any knowledge of the application.

MB
-- 
Mark Baker, Chief Science Officer, Planetfred, Inc.
Ottawa, Ontario, CANADA.      mbaker@planetfred.com
http://www.markbaker.ca   http://www.planetfred.com

Received on Thursday, 28 March 2002 21:03:54 UTC