The itinerary web services, also known as on-ramps, are the ones that allow clients trigger ESB exchanges and processes by delivering messages to the ESB for their processing.
The main inputs to trigger the message processing by an itinerary in the ESB are:
The payload: It's the actual message that is meant to be processed. When using the out of the box Itinerary web services, this payload must be an XML document, but we could create our own itinerary service to receive non-XML payloads for processing through itineraries. These could be meant to process flat files or other kinds of files.
The itinerary: We need to tell the service which itinerary the payload should go through. We can do it explicitly by attaching the actual itinerary XML representation, or by providing the information required to resolve the itinerary to be used. The ESB Toolkit provides two sets of services (in WCF and ASMX flavors) that support these two ways to specify the itinerary.
