SOAP vs. RPC

[Matthew Phillips]

I'm new the web services. It seems like these are competing methods to accomplish the same goal. Am I correct in that assessment? If so, will one of these eventually disappear.

[Lasse Koskela]

Web Services (which are essentially standardized communication over SOAP) contain both a document-style and an rpc-style way of using web services. The RPC-style invocations are very similar to other RPC technologies. It's just based on (standard) XML, which is a lot easier from platform independence point of view.
In other words, Web Services are in a way RPC. Plus some extra.
So, RPC is (still) not going anywhere - in fact you could say the opposite. It's becoming more and more common.
[ May 06, 2003: Message edited by: Lasse Koskela ]

[Ramesh Nagappan]

Web services are :
- Business functionalities exposed as services over internet.
- A programmable application logic providing data and services to other applications over internet.
- Based on Internet protocols and standards.
- Based on XML standards and provides cross-platform and cross-language solution.
There are two types Web-services communication styles:
RPC-oriented Web services:
Synchronous, point to point, not persistent
Sends data formatted to a procedural call
Document-oriented Web services:
Data formatted as an XML document
Asynchronous service interactions (like Messaging)
SOAP facilitates communication in Web services. It establishes Wire protocol for communication �similar to� IIOP for CORBA and JRMP for RMI. But in case of SOAP, XML is used for data encoding as �text� based protocol. SOAP Supports XML-based RPC Web services and XML Messaging (Document oriented Web services.
To add more clarity on SOAP,
SOAP is NOT a component model like EJB, JavaBeans etc.
SOAP is NOT a programming language like Java or C++.
SOAP is NOT an alternative to distributed computing and does not replace RMI or CORBA.
SOAP is NOT a solution for all !
In Java Web services, JAX-RPC facilitates RPC base Web services and JAXM/SAAJ facilitates Document oriented Web services.
Send me an email: [email protected], if you need a copy of my Web services presentation.

[Ram Kumar Subramaniam]

whats SOAP over http and SOAP using mail ? How do u classify it as RPC or document type ? Or is the question in appropriate ?

[Lasse Koskela]

SOAP over HTTP differs from SOAP over SMTP (mail) on the transport level (which is kinda obvious from the names:)
In other words, the two differ from each other in the way the SOAP Envelope is encoded into the wire protocol message for transportation.

[Matthew Phillips]

It looks like I need to do some more reading because I apparently don't understand the topic as much as I thought I did (as little as that is). Thanks for the feedback.