Hi Ron;

I agree that WSDL is not sufficient to provide all metadata 
associated with security, semantics, QoS, SlA ..etc. I don't think 
WSDL is supposed to provide those semantics either. As for security 
within the SOA context, the message level security that can be 
defined in SOAP headers (as defined in WS-security) is not 
sufficient. The SOA infrastructure needs to provide another level of 
security, such as authorizing the client, for the access of the 
service (i.e. before sending the actual soap request - client 
request is accepted only after the autorization is passed and then 
the message level security could take over). For this to happen some 
sort of security policy need to be implemented external to the 
service that WSDL describes. May be XML appliences could help on 
this. 

As to service semantics, this is a challenge because trying to add 
semantics to WSDL requires establishing good data semantics. I think 
we have long way to go to tackle semantcs part in standard way. For 
now tactical solutions in development team communicate some data 
semantics external to WSDL. 

QoS ans SLA is something that is responibility of the SOA 
infrastructure rather than at the service (wsDL) level. I think 
this  requires some sort of service management tools for monitoring 
and managing services based on policies published in Service 
registry tools. may be WSDM standard helps on this. Again, defining 
SLA within WSDL for client consumption, I think, may not be 
practical. 

When you say "process", I assume you mean business process here. In 
that case, BPEL is used to describe the business process. Each 
service described in WSDL can be orchestrated using BPEL to 
implement higher level business service (i.e. business process).

I know I am not helping you as such with your question - since you 
ask for real example contract that handles these items. I am just 
trying to point out that all those tasks are not in the scope of 
WSDL and that other SOA infrastructure elements and polices are 
required.

Regards,
Awel Dico

--- In [email protected], Ron 
Schmelzer <[EMAIL PROTECTED]> wrote:
> Hi All --
> 
> As you all know, one of the key parts to making loosely coupled 
Services 
> work is a well-defined contract that identifies both functional as 
well 
> as non-functional requirements for Service providers and 
consumers. By 
> now, you also probably realized that WSDL by itself is not 
sufficient to 
> provide all the metadata needed for loose coupling and late 
binding. 
> Other metadata are needed including security, semantics, QoS, SLA, 
> process, etc.
> 
> So, what we are looking for are actual examples of real-world 
contracts, 
> or templates for contracts that you are using in real-world SOA 
> deployments, or at the very least, guidance for how those 
contracts can 
> be defined.
> 
> So, help anyone?
> 
> Thanks in advance!
> Best,
> Ron
> 
> -- 
> _____________________________________________________________
> Ronald Schmelzer
> [EMAIL PROTECTED]
> Senior Analyst
> ZapThink LLC
> Direct: 781-577-2779 / Main: 781-207-0203






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