Let's face it, WS-BPEL 1.1 was not a great standard, and left so much out that many end users and vendors found it useless. In response, the vendors put a ton of proprietary extensions in their BPEL 1.1-based products, thus diluting its value to the point of "Why bother?" This was a dirty little secret in the world of SOA. Considering that BPEL 2.0 is on the horizon, I think it's time we began to talk about what's really there, how you can fix it, and what you need to do to get from point A to point B.

What's most frustrating about the issues here is that orchestration is indeed a core feature of SOA...the configuration component that makes orchestration that part of the architecture providing agility. Orchestration, at least the notion, is a necessity if you are building an SOA. It's the layer that creates business solutions from the vast array of services and information flows found in new and existing systems. Orchestration is a god-like control mechanism that's able to put our SOA to work, as well as provide a point of control. Orchestration layers allow you to change the way your business functions, as needed, to define or redefine any business process on-the-fly. This provides the business with the flexibility and agility needed, and is the core value of SOA.

Ranting
While I've been ranting and raving about this for some time, Dave Chappell does a much better job of explaining the limitations (from his blog www.davidchappell.com/blog/2005_11_01_weblog).

"Promoting BPEL's portability helps significantly in the first of these goals, since customers like the idea of not being locked in to a single vendor. But actually making customers successful has typically required extending BPEL in proprietary ways, which works against the language's promised portability. While BPEL purists might argue that all of these extensions should be provided via programming language-neutral web services interfaces, this isn't what's actually happening in the products."

With huge investments in BPEL by the larger SOA players out there, the dirty little secret is that BPEL 1.1 never really worked as advertised, and the amount of custom and proprietary extensions required to make the technology useful meant that the money, time, and effort was pretty much wasted if "standards and portability" were the goals.

The hype behind the standard, and the larger vendors supporting it, has really pushed the notion of BPEL in the last few years. However, those who have had to build solutions using the base 1.1 technology have run into many roadblocks, and thus the vendors have responded with their own unique extensions and toolsets. Are we employing a standard that's living and breathing, allowing us to protect our investment in our work, or just an instance of a vendor's tool? This is now a key question to answer.

BPEL 2.0
Enter WS-BPEL 2.0, and another opportunity for vendors to get BPEL right. You can find the draft specification on the OASIS site (http://docs.oasis-open.org/wsbpel/2.0/wsbpel-specification-draft.pdf), which I read, and discovered that this spec was much improved, but many issues still remain. For instance, there are considerable differences in WS-BPEL 2.0 compared to its previous 1.1 version. The major differences include syntax changes to the language, the inclusion of new features including parallel for-each, and modifications to the semantics of existing constructions, such as compensation handling. There are a few more, and I urge you to read both the 1.1 and 2.0 specs before diving into BPEL, or assessing how deep you're in already.

What if I already implemented orchestrations using BPEL 1.1, what do I do now? In short, you purchased Beta and the world is moving to VHS. I thought that this article by BEA's Alexandre Alves (http://webservices.sys-con.com/read/155617_1.htm) did a good job of summing things up.

"For all but the simplest business processes, migration from BPEL 1.1 to BPEL 2.0 is not an easy task. Some of the syntactic changes can be automated as shown [in the Alexandre Alves article], however the semantic differences, especially when dealing with links, messaging, compensation handling, and data manipulation, will demand a comprehensive and time-consuming process."

What bothers me most about this issue is not the fact that the standard, at least in some respects, is letting SOA down, but that orchestration is such a powerful need within SOAs, and there are few other alternatives that offer a better approach, standardized or not. Thus, end users who are tasked with building solutions using emerging SOA standards such as BPEL should begin to lean on their vendors now, as well as get more involved with their respective standards organizations.

I suspect the BPEL sales guys will get some angry calls around Christmastime from their users, perhaps more so considering the use of many proprietary extensions to get around the limitations of BPEL 1.1. Not a good way to start a standard. I guess that's why my old boss told me never to buy products until release 3.0.