The “WebServicesDevGuide.PDF” can be found in your developer_install_dir\doc\guides folder. It explains the differences pretty well.
In general, document literal or message-based web services are more interoperable with other soap clients than soap-rpc services. For this reason, most of the web services work I have done for my clients has been message-based.
It is much easier to expose an existing IS flow or java service as a soap-rpc service (in essence you don’t need to do anything). However, if you will be invoking IS flow or java services from other platforms such as .Net, you would probably be wise to create flow services that extract the payload from soap messages sent to the IS server’s soap processor. This approach also gives you more control over the soap message that the client needs to prepare and send.
HTH,
Mark
#webMethods#API-Management#soa