The OGSA® Resource Selection Services specification defines an abstract interface for perform-ing queries used to 
select resources for any purpose. The specification also narrows the abstract interface for the specific purpose of 
selecting a Basic Execution Service on which to instantiate an activity based upon a Job Submission Description Language
 document, and defines renderings for such services based on both the WS-Resource Framework and the WS-Transfer draft. 
The final part of this specification gives a simple language for defining a function capable of ranking one candidate 
for execution versus another.