RE: Initial correlation of ebXML Transport requirements with CORB A services

[Andrew Watson <andrew@omg.org>]

David,

You wrote:

> But doesn't using Corba, require that an ORB is implemented at each end of
> the two parties that want to communicate.

True. And using XML requires an XML parser at each end. Furthermore, ORBs
have standardised APIs, while there's currently no standard API for
interfacing to XML parsers (although there are three or four sets of people
who all think theirs should be the standard). Hence using XML may well lock
you into using one particular vendor's product.

>                                           Not everyone will want to
> implement an Orb even if it is available from multiple suppliers with open
> standards.

No end-user should consider implementing an ORB - as you say, the right
thing to do is use one off-the-shelf. There are about 30 to choose from,
some open source (useful if your budget is tight).

> It's also quite possible to define the interfaces to objects in terms of the
> documents they accept and generate in turn, for example look at the way the
> eCo specification specifies "Services" and "Interactions".

That's called "designing your own protocol". It's perfectly possible, but
takes time,effort, and is error-prone. Remote Procedure Call (the
predecessor of remote object technology such as CORBA) was designed in the
80s precisely so end-users could avoid designing a new protocol for each
application.

> You can also with XML Schema's have documents that are extensible and can
> inherit characteristics from other documents (a colleague at Commerce One is
> one of the author's of the upcoming W3C Schema spec).

You can, of course, also do this with CORBA IDL.

> This means that you can achieve the benefits of an object oriented approach
> without having to implement a particular architecture on your system.

No, it means that you're designing your very own architecture.

Please don't misunderstand me, I'm a great advocate of XML, but I feel very
strongly that (like any technology) it *must* be used appropriately. I'm
horribly afraid that eCommerce in general is going to be held back if
everyone goes out and re-invents the wheel (whether using XML or anything
else) rather than using appropriate off-the-shelf technology that's already
widely available.

                            Regards,

                                 Andrew
 Andrew Watson                              Tel:     +1 508 820 4300 x111
 Vice President & Technical Director,       Fax:     +1 508 820 4303
 Object Management Group,                   Email:   andrew@omg.org
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