To understand why I subsequently withdrew from the group one has to understand the dynamics of a standards group, especially one that is doing fundamental design (always, I suspect, a bad idea) rather than just standardizing existing practice.

In a group doing fundamental design there tend to be two sources of power – Companies you have to keep happy because they are so ridiculously powerful (e.g. IBM and MS in BPEL) and people willing to put in sweat equity.

Nick, from Oracle, fell into the later camp. He and I talked and he has a very different vision of what WS-CDL should be then I do. We were unable to come to any kind of consensus on the right approach. Once I realized that Oracle was going to fund Nick to the point where he could work on WS-CDL full time I approached my management and gave them a choice.

We could either have me working more or less full time on BPEL and use my sweat equity there to make sure the group went in the direction we wanted or we could do the same for WS-CDL. What we couldn’t do is both (alas, cloning doesn’t work yet). From a business perspective the decision was trivial – BPEL won and I dropped off WS-CDL.

To be clear, Nick was very willing to listening to my concerns. He just disagreed and frankly I can understand why he disagreed. We approach the problem from very different view points. But in the end he was willing to spend as much time as it took to get his points accepted and from a business perspective I couldn’t justify matching his time investment.

Later on, btw, when the spec was getting ready for final review Steve Ross-Talbot directly contacted me to get a review. I didn’t see much point in doing a review since the spec had diverged so widely from the direction I thought it should take and sending in a long list of comments repeating points I’d already made to the group in the past didn’t seem very productive. But in the end it didn’t matter, at the time of the review I was completely snowed under in work and there was simply no time available to do a review.

In regards to BPEL, I have said many times that I feel BPEL is outrageously premature. In an ideal world BPEL wouldn’t have happened for at least another five or maybe ten years. But unfortunately politics doesn’t always work in the best interests of the industry. Given who was behind BPEL and their power over customers we were left with no option but to at least make sure BPEL was designed in a manner that favored our interests.

As for your comment that WS-CDL’s format isn’t too hard to use if you have tools to help I would recall the following post I sent to the BPEL list on the same subject :

I remember in the late 1980s when everyone argued that source code was dead and all programs would be written using UIs.

I remember the early 1990s when everyone argued that no one would ever directly author HTML.

I also remember the late 1990s when everyone (myself included =( ) argued that it didn’t matter if XML was human editable since everyone would use tools.

It’s funny how often everyone is wrong.

Just a thought,
Yaron

You may or may not have a valid point but I don’t see the same point being made about BPEL which could also be said to be jumping the gun given it has been very much vendor and not user led.

We can, in the Choreography WG, at least cite user communities who we have actively enaged with to ensure that the work is directed at solving their problems.

I hope that both of you actually try to build stuff using WS-CDL. It really isn’t that hard to do when you have tools to help – and they are available. I don’t think anyone has ever suggested coding directly in WS-CDL’s XML representation. You might even be pleasantly surprised.

As to all of the other criticisms I’d like them to be put to the WG rather than aired here first. At least that way, if we failed to address them, you would have the moral high ground. Alas at this point you have little to stand on.

Shame given the active contributions of the past.

What I’m worried about is that people might try to use WS-CDL for protocol design rather than just for simulation. That would lead people to do dangerous things like rely on WS-CDL’s state alignment features. By externalizing state alignment from the protocol messages you signifigantly increase the chance that the protocol designer will toast their performance by introducing extra round trips. You also guaranteed a badly designed protocol because a well design protocol should provide state alignment as a direct consequence of the messages themselves, not as separate meta-data.

Sigh, I’m not looking forward to the mess WS-CDL is bequeathing us.

Actually thats the important thing, to analyse a business protocol or a composed serice behaviour, you want to find the critical points where multiple services in the choreograhy may disagree about their state and intended outcome. Exactly those conditions are easier described if you dont have programming model which is nearly impossible to be analysed. Especially with all those side effects introduced by variables.

This is BTW the exact same reason why I dont think Abstract BPEL is a good thing for defining protocols.

Gruss
Bernd