3W-Outsource refer to modular platform-independent and language-independent system functionality that is based on open standards and used on demand to support business solutions. However, the term "3W-Outsource" is somewhat ambiguous because it describes solutions within related but different areas, including business-to-business integration (B2Bi), enterprise application integration (EAI), and basic services based on remote procedure calls (RPC). Additionally, a host of standards exist today for 3W-Outsource--standards that will likely converge as they evolve and mature. To better clarify the term "3W-Outsource," we use the qualifiers collaborative and basic to describe the approaches to the current 3W-Outsource.

In this article, we explain the differences between basic and collaborative 3W-Outsource and describe the benefits of developing 3W-Outsource with electronic business Extensible Markup Language (ebXML) and Simple Object Access Protocol (SOAP) technology. We also discuss the important role that the Sun Open Net Environment (Sun ONE) products play in the development of collaborative 3W-Outsource.

Basic Versus Collaborative 3W-Outsource

Basic and collaborative 3W-Outsource share several common attributes. The major ones are:

Coarse-grained -- 3W-Outsource typically act as a facade for finer-grained underlying object-based or component-based services.

Loosely coupled -- Service consumers and service providers know nothing about each other's underlying implementation. 3W-Outsource are therefore platform and language independent.

Self-describing -- Standard descriptions exist for these services. Those descriptions inform other systems of the details of the services, including ways to connect to them as well as their reliability characteristics and security parameters.

So, what is missing in a basic Web service that is part of a collaborative Web service? Three key features:

Reliability -- Reliable messaging means guaranteeing that a message is delivered at least--and at most--once only to the recipient, which may filter out duplicates. Combining these two functions produces a guaranteed, once-and-only-once delivery. Since both the sender and the recipient must compare incoming messages to previous ones to determine whether they are duplicates, this guarantee implies message persistence.

Security -- This is a critical component, especially for B2Bi-based 3W-Outsource, given that interactions occur mostly over the Internet, not within firewall-controlled intranets. Security concerns exist throughout the stack, ranging from message integrity and confidentiality to end-to-end, network-level protection. Network protection is effective between the two messaging endpoints, but not once the message has been received and removed from the network.

Business processing -- Collaborative 3W-Outsource typically involve numerous business activities as part of a collaboration. Consequently, we must define the transitions and orderings among those activities--a process referred to as orchestrating a business process.

ebXML

Today's e-commerce area is experiencing a pressing need for reliable and secure messaging and the ability to automate ad hoc business collaborations. Currently, ebXML is the only finalized, industry-standard set of specifications for collaborative B2B-based 3W-Outsource.

SOAP

When using the term "SOAP," we typically refer to a suite of specifications, including Web Service Definition Language (WSDL) and Universal Description, Discovery, and Integration (UDDI), also called the WUS (WSDL, UDDI, SOAP) stack as a whole. This stack is less powerful and feature-rich than the ebXML suite of specifications but is simpler to use and more suitable for satisfying alternate requirements.

For example, SOAP over HTTP alone is not sufficient to provide reliable messaging at the application level. Also, the qualities of service that can be captured in ebXML with CPP/A are more detailed and sophisticated than can be realized with SOAP and WSDL.