WSDL
Document Sample


WSDL / Business Process Stuff
Breakout
Outline
• “Service description”
– WSDL next steps
– WSDL issues
• Choreographing Web services
WSDL Relation to ebXML
CPP/CPA
• tpaML
– “interface definition”
– Binding
– Security / QoS
– “orchestration”
• tpaML is in the same space as WSDL + “WSEL”
+ business processs stuff + agreements
• CPP/CPA = evolution of tpaML
• CPP = Collaborating Protocol Profile, CPA =
Coll. Protocol Agreement
Issues
• Boundary from top-down and bottom-up
w.r.t. service descriptions
– What’s horizontal vs. vertical
– “Atoms” vs “molecules”
• Overlap of CPP/CPA with UDDI
• Are service descriptions queriable?
• How do service descriptions relate to other
W3C work items?
Service Description: Moving
Forward
• Start with ebXML TP vs start with WSDL
– ebXML TP has had a lot of work done on it
– Bottom up approach is more likely to get
adoption in the “Web” community
– Need to identify high level approach and then
look at options
– Consensus on need for a service description
WG
Service Description &
Sequencing
• Service descriptions need to include
information about proper usage of the
service (w.r.t. sequencing)
– Separate service interface descriptions from
service usage
Service Descriptions
Requirements
• What is core and what is an extension?
• What extensions are “standard” extensions
vs private extensions?
• Description of a feature does not mean
anything about how it will be supported by
a specific service implementation
“Service Description” Scoping
• “Interface” definition
• Sequencing
– Does not indicate what happens; only possible
usage of a set of operations of a service
• Orchestration of services (both “local” and
remote)
– Defines a specific sequence or flow of activities
Orchestration
• Issues:
– How do we get this to work without locking
into QoS problems
• Need flexible business transaction models for
service orchestration to work
• How do the various business transactions activities
relate to transactional properties of business
processes
Orchstration Scoping
• Scoping:
– Static processes to dynamic processes
– Who’s going to deal with transaction stuff
Compositions as new services
• What do services need to provide so that
they can be composed?
• Can behavior of compositions be described
in an extensible way (not special case on
failures for example)
Get documents about "