Home > Ask the SOA Experts > Questions & Answers > Why is there a need for BPEL4WS for orchestrating Web services?
Ask The SOA Expert: Questions & Answers
EMAIL THIS

Why is there a need for BPEL4WS for orchestrating Web services?

Doron Sherman EXPERT RESPONSE FROM: Doron Sherman

Pose a Question
Other SOA Categories
Meet all SOA Experts
Become an Expert for this site


Digg This!    StumbleUpon Toolbar StumbleUpon    Bookmark with Delicious Del.icio.us   


>
QUESTION POSED ON: 25 April 2003
Why is there a need for BPEL4WS for orchestrating Web services? Why not simply use Java and JAX-RPC?

>
BPEL4WS (like other flow abstractions) is driven by the need to coordinate asynchronous message exchanges across services distributed over the net. This means that you have to be able not only to invoke a Web service (a la JAX-RPC) but also wait to receive an asynchronous callback prior to invoking the next service. More sophisticated use cases include parallel flow of execution, join patterns, exception management and compensating business transactions. These constructs and such semantics don't exist in traditional languages like Java and request/reply mechanisms such as JAX-RPC. To implement the above requirements, the programmer has to write a lot of code.

BPEL4WS solves that problem by offering a base set of activities and semantics to glue them into a flow. <receive>, for example, is an activity that allows you to define a rule where execution of flow is suspended until a message is received. Implementing this in Java is more than a trivial task. To summarize, asynchronous message-driven interactions drive the need for flow coordination. BPEL4WS offers a standard approach to implementing the flow logic. Orchestration servers offer *containers* where BPEL-based flow logic is executed, monitored and managed.

Here is a link to an example of the kind of applications/long-running processes that can be build by stringing together asynchronous services.


Digg This!    StumbleUpon Toolbar StumbleUpon    Bookmark with Delicious Del.icio.us   



RELATED CONTENT
BPEL
Oracle SOA Suite Developer's Guide by Matt Wright
BPEL tutorial
Co-evolution of BPMN and BPEL drives BPM in SOA settings
UML modeler includes BPMN support
BPM Special Report: What you model is what you monitor
Verizon uses BPEL app to cut down on code, check for fraud, and go green
Visual orchestration tool addresses event processing and SOA
SOA, BPEL working on the railroad
UML and SOA the Microsoft way
Oracle links SOA, data services, BI and BAM
BPEL Research

RELATED GLOSSARY TERMS
Terms from Whatis.com − the technology online dictionary
BPEL  (SearchSOA.com)

RELATED RESOURCES
2020software.com, trial software downloads for accounting software, ERP software, CRM software and business software systems
Search Bitpipe.com for the latest white papers and business webcasts
Whatis.com, the online computer dictionary



Search and Browse the Expert Answer Center
Search and browse more than 25,000 question and answer pairs from more than 250 TechTarget industry experts.
Browse our Expert Advice



SOA Governance White Papers - BPM, EDA, IT Governance
About Us  |  Contact Us  |  For Advertisers  |  For Business Partners  |  Site Index  |  RSS
SEARCH 
TechTarget provides technology professionals with the information they need to perform their jobs - from developing strategy, to making cost-effective purchase decisions and managing their organizations' technology projects - with its network of technology-specific websites, events and online magazines.

TechTarget Corporate Web Site  |  Media Kits  |  Site Map




All Rights Reserved, Copyright 2001 - 2009, TechTarget | Read our Privacy Policy 		  TechTarget - The IT Media ROI Experts