The above diagram illustrates the general path of EDI transactions and allows us to visualize how we can evaluate and "track" the flow of EDI transmissions. The Mailbag Report, as seen in the chart, is sent information from a Value Added Network (VAN) to identify which envelopes were recieved. In another measure taken for transaction tracking, the Envelope Report identifies the sender and receiver qualifier ID's as well as the Interchange Control Number for each document that is transmitted. Both the Mailbag and Envelope Reports are given information by your own VAN, and the involved trading partner likely has access to their own Mailbag and Envelope Reports from their own VAN as well. These measures give us the ability to track EDI transmissions from one server to another.