DAML-S and UDDI

"Delivering Semantic Web Services" [1] presents the problem of 
distinguishing a US-based service for weather data from a service for 
US-area weather data:

"The problem of UDDI is that it does not have an explicit representation 
of what the Web Service does. Therefore, the search for a Web Service 
with a given capability becomes very difficult. As an example, to locate 
a Web Service that reports weather information within the US, a 
requester may look for all the Web Services that contain a TModel 
associated with a classification of services such as NAICS [18] which 
are specified as weather providers, and all the Web Services 
descriptions that contain a TModel that associate the Web Service with 
the US, and then look in the intersection of the results of the two 
searches. The problem of course is that this type of search cannot 
distinguish between weather services that provide information about the 
US, from US based weather services that may provide information about 
the weather in other countries. Overall, because UDDI misses any form of 
capability representation and capability matching, it is extremely 
difficult to find Web Services with a desired capability using UDDI."

It is strongly suggested in [1] that DAML-S can solve this problem. It 
is perhaps even suggested (because [1] references [2]) that representing 
DAML-S profile information in UDDI is intimately involved in the way 
that DAML-S solves this problem. But in fact [1] does not actually say 
how to solve this problem. Is that because the solution is so obvious? 
Let's see.

Obviously this problem could be solved if we could distinguish 
qualifiers on the service from qualifiers on the output of the service.

One way to add qualifiers to a service in UDDI is to add keyedReferences 
to the CategoryBag of the service; these keyedReferences can then 
qualify the service by associating it with  "positions" in a 
classification. (So, e.g., this could qualify a service as a weather 
service.)

In [2] it is suggested to add additional keyedReferences for the 
attributes in the DAML-S profile, to the CategoryBag of a service. For 
example:

KeyedReference
    KeyName= Output
    KeyValue= phenomenologyOntology:weather
    TModelKey= "UUID of the DAML-S Output TModel"

might be added for the example. But this still doesn't solve the 
problem, because it doesn't actually qualify the output, as to its 
geographic region. So something is still missing.

Perhaps the "DAML-S Output TModel" also needs to have keyedReferences 
that qualify it, in the way that a service does? Is that the solution?

Jeff


[1] 
http://www.ri.cmu.edu/pub_files/pub4/paolucci_massimo_2003_1/paolucci_massimo_2003_1.pdf
[2] http://eprints.ecs.soton.ac.uk/archive/00007778/

Received on Tuesday, 5 August 2003 13:23:30 UTC