Over the years a large number of technologies have been devised in order to describe service interfaces, e.g., WSDL (Booth & Liu, 2007), combine services in a process-oriented way, e.g., WS-BPEL (OASIS Web Services Business Process Execution Language (WSBPEL) TC, 2007), provide support for transactions, e.g., WS-Transaction, and cover non-functional properties (NFP) of services such as security aspects and the like, see for instance WS-Security and WS-Policy to name just a few (Erl, 2007). There is in an overwhelming stack of technologies and specifications dubbed WS-*, covering most aspects researchers have faced thus far. There remain nonetheless a number of outstanding issues (Papazoglou, Traverso, Dustdar, & Leymann, 2007) some of which are of a general technical nature, and some, indeed, are specifically related to NFPs. The latter will be dealt with in more detail in the next section.
A Petri Net-Based Method for Compatibility Analysis and Composition of Web Services in Business Process Execution Language
