In the
WSDL 1.1 W3C Note, you will find some
extension elements SOAP provides in order to extend WSDL. In the soap:binding extension element, you may specify a style (rpc or document) that will be the default for each contained soap: operation element. Then, in each soap: operation element, you may override the style specified in the soap:binding element. You can thus specify for each operation whether the contained SOAP message is to be considered an RPC message or simply an XML document.
Then, for each SOAP operation you might specify an input, an output and a fault element. In turn, those input, output and fault elements might contain soap:body and soap:header element which feature an attribute named "use" and whose valid values are literal or encoded.
As you can see you can customize each operation along two styles (RPC and Document) and two uses (Literal and Encoded). As a result, the following are all valid couple for SOAP messages:
1. RPC/Literal
2. RPC/Encoded
3. Document/Literal
4. Document/Encoded
However, for compatibility reasons, the Basic Profile 1.0 does not allow the use of Encoded. Thus, in order to be compliant with the Basic Profile you must choose either 1 or 3.
[ April 21, 2005: Message edited by: Valentin Crettaz ]