As I worked with Paul Kulchenko on his article, The Evolution of SOAP::LITE, I realized that much has changed since I last looked at this technology.
You might want to read the entire text because Paul discusses his own SOAP evolution that includes his authoring of the SOAP::LITE module. But the one thing I thought you might be most interested in now are his views concerning the direction of SOAP. Here’s what he has to say:
The direction SOAP is moving
More complex systems are being built on top of these basic levels of interoperability. SOAP development is moving in two orthogonal directions: creating extensions using SOAP extensibility and implementing complex conceptions.
The most important extensions that will influence future of SOAP are: SOAP Messages with Attachments (describes how to wrap SOAP message into MIME envelopes together with various attachments, like images or binary objects), SOAP Security Extensions: Digital Signature (describes how to implement XML Signature specification in SOAP to add security features on protocol level), and encryption (based on XML encryption, that brings other security features, like confidentiality to the SOAP level).
Complex implementations include routing through several SOAP processors (intermediaries), reliable messaging, and asynchronous processing are also planned. Recent specifications from Microsoft and IBM are trying to address these aspects. SOAP-RP from Microsoft describes message paths that two-way message exchange, and WSFL from IBM defines usage and interaction patterns for web services.
Of course there’s lots more happening with SOAP than what’s listed here …