Metadata and Metamodeling


The Internet is a giant computer network connecting many companies that are constantly trading, exchanging business transactions and information. For many years, companies struggled to find a common way to exchange information. Each used different data models, different communication protocols, incompatible applications, etc. XML specifications and efforts spent for standardization helped businesses to design new common business languages such as eBusiness XML [35] and Simple Object Access Protocol [20] for data exchange protocols, Web Services Definition Language (WSDL) for business service interface definitions [120], Universal Description, Discovery and Integration [108] for business service descriptions, and others like WS-Security [119], WSIL [121], and WSRP [122]. Although these specifications are not the only ones, they are mostly used and developed by organizations with members from many leading companies.

Defining Messages

XML specification allows structured data models to be represented in verbose text formats. This simplifies parsing and handling data in XML format. On the other hand, verbosity is a disadvantage for communication bandwidths, because the size of an XML document can be several times larger than the size of the actual data inside the document. The increase in network communication speeds can hide this problem. In addition, because XML is textual, it can be highly compressed before transmission. Applications can leave data editing, formatting and validation to third party software while focusing on other parts of the applications.