RE: What are web services good for? (WAS: RE: Two new features o fthe Web)

[Michael Brennan <Michael_Brennan@allegis.com>]

> From: jwells123 [mailto:jwells123@email.msn.com]

<snip/>

> What I'm not clear about is the feasibility of distributing 
> systems across
> the Internet. In Wrox's "Introducing .NET," the chapter on 
> Web Services
> tells me it's a Good Idea for the components of a site to be 
> hosted all over
> the Web because then the publishers of those components can 
> upgrade them
> without having to distribute the upgrades to clients. I can 
> think of four
> potential problems to begin with:
> 
> 1. Upgrading software used by your site can be hairy when you 
> DO know about
> it and approve of it, let alone otherwise.
> 
> 2. The Internet isn't known for reliability. Sites which must 
> rely on remote
> components can use message queuing to improve reliability, 
> but at the cost
> of response time.
> 
> 3. Speaking of response time, component developers have been 
> taught for
> years that it's a sin to make method calls across apartments, 
> let alone
> across processes, machines, networks, or the Internet.
> 
> 4. What happens if the provider of a Web Service folds?
> 
> I've seen all four of these problems when working with 
> CyberCash (they've
> filed for Chapter 11, though they still seem to be there). 
> They provided a
> remote credit card authentication service which, in fact, had 
> a reasonably
> nice COM interface not unlike a Web Service.

All sound points. Some of the scenarios promoted are pretty silly. However,
to take the example you cite of CyberCash, how do you do credit card
authorization without invoking a remote service? The credit card companies
aren't going to distribute authority for credit card authorization among
every vendor who wishes to support credit card purchases. In scenarios where
such interactions over a global network are necessary to do business, web
services are the most promising solution, IMO. However, promoting the
concept of distributed components on the web just for the sake of
distributed components on the web is pretty silly. You are right to question
that, but don't lose sight of those cases where businesses are stuck with
either using error-prone manual processes (and snail-mail or faxes), or turn
to some sort system that can let applications interact across the web. And
when choosing the latter course (which is mandatory for any business that
engages in ecommerce), it's much better to be able to do so without
requiring specific client software to invoke one specific vendor's services.