Gerald Brose <gerald.brose@x...> wrote in message news:<2i5gvaFhvjq7U1@u...>...
 
> The point for using Web Services is not that you cannot model
> services using CORBA, or that Web Services would be capable of doing
> everything better than CORBA can. Both statements are just wrong.
> This discussion is popping up again and again, as if Web Services
> were trying to be CORBA's successor for RPCs...
> 
> The point is that Web Services are better suited than CORBA for cross-
> domain B2B applications because of a few inherent properties of XML
> messaging, frequently summarized as loose coupling. (Extensibility,
> finer-grained contracts, marshalling with partial type information,
> etc.).
> 
> CORBA delivers better performance, and the type-safe IDL inter-
> faces are well-suited for closely integrated intra-domain
> applications.
> 
> For loosely coupled application-to-application communication
> that cannot rely on a homogeneous middleware layer such as
> CORBA and may need to be rearranged to integrate more systems
> every other month, you will be better off with Web Services.
> XML messages are especially suited for document-style inter-
> actions, and the performance hit is tolerable in many of
> these applications. People also tend to believe that the
> firewall-friendliness of HTTP is a good thing...
> 
Totally agree.  The comparison between IDL and WSDL or Web service and
CORBA is meaningless because they address different abstraction in
which IDL addresses object model and WSDL addresses document model. 
Web service shall be developed as an MOM-based middleware which
requires a document model instead of RPC-based or RMI-based middleware
which requires an object model.   In this way, Web service and CORBA
are complementing each other instead of competing each other. 
However, the focus and current development on RPC-based Web service is
very wrong, IMO.  The mapping between IDL and WSDL makes no sense.  I
don't know when market will realize this and shift the focus to
MOM-based Web service to replace Tibco, MQ, JMS, EAI, and bunch of
proprietary message middleware, so we can have a platform, language,
and vendor independent MOM-based Web service and RPC-based CORBA. 
What a wonderful world!