8.2. SOAP Envelope, Message Exchange, and Processing Model
The fundamental communicating entities from SOAP's point of view are “nodes,” as shown in Figure 8-1. A SOAP message start at the original sender node, proceeds through zero or more intermediate nodes, and terminates at the ultimate receiver node. A message always has a top-level element, “Envelope,” in the soap-envelope namespace.
Figure 8-1. Message transmission model
Although SOAP does not provide message routing, it fundamentally recognizes that messages can pass through intermediate nodes on the way to their destinations.
This protocol does not have a traditional versioning label. ...