The internal format managed by the XML information server facilitates the interaction with business partners who are compliant with different B2B standards. For that matter, the XML information server can even support partners that can only accept flat-file data formats. Elements of business documents that cannot fit in enterprise systems are made natively persistent. Figure 3 . This layer is implemented as part of the transformation engine.
Services represent units of work.
Business processes specify the sequence and definition of service invocations and business documents. When the number of business processes and their respective instance is become large, a workflow engine can easily be added into the architecture to manage thousands of concurrent business processes in a very dynamic environment where partners are added, removed or changed daily. It is difficult to estimate the performance penalty imposed by the introduction of such information server versus a relational store from which XML documents are assembled on demand. The more complex the document structure becomes, the more advantageous it is to keep it assembled. It is also difficult to assert the impact of using digital signatures.