June 1, 2010
Are you interested in helping to shape Microsoft’s future rules products?
Microsoft is running a survey on rule engines in general, and its own rule products (WF Rules, MS BRE) in particular through the end of this week – June 4. (I would have blogged it yesterday, but was off due to holiday.)
The survey should take approximately 5 minutes to complete. If you have used the WF Rules product, you will get a few additional questions about your usage of the features. If you only use non-Microsoft rule engines, your participation is welcome as well.
Your input is appreciated.
Microsoft Rule Engine survey
February 5, 2010
I am often asked to describe the rule engines that Microsoft ships. (The first question being: “Microsoft has rule engines?”) This question frequently comes from folks who know rules, but don’t know .NET. This post is specifically written to answer the question. Should the offerings change in the future, I will update this post as needed.
As always, this is not an official Microsoft statement. Questions about the future directions for these products should be directed to Microsoft.
As of this writing, Microsoft is currently shipping two rule engines. They are aimed at somewhat different audiences as described below.
The first rule engine is called the Microsoft Business Rule Engine (sometimes called “MS BRE” or “BRE”) and it has shipped as part of BizTalk Server since early 2004. BRE has shipped in BizTalk Server 2004, BizTalk Server 2006, BizTalk Server 2006 R2, BizTalk Server 2009 and I’m sure it will be included in the upcoming BizTalk Server 2009 R2.
The second rule engine is part of Windows Workflow Foundation in .NET, it is the Windows Workflow Foundation Rules Engine (sometimes called “Workflow Rules” or “WF Rules”). The WF rule engine originally shipped in late 2006 as part of .NET 3.0. It was also included in .NET 3.5 and .NET 4.0. If you are running Windows 7, Windows Server 2008 R2, Windows Server 2008, or Windows Vista or have installed .NET 3.0 or higher – you already have the WF rule engine on your computer. Update: I have an additional post specifically about rules in WF4.
Comparing MS BRE & WF Rules
Here are some comparisons of these engines written by other folks. Charles Young has written extensively on this topic.
A Short Summary Of Differences For Those Who Know Rules
If you asked me to summarize differences for a rules specialist, my comments would be along the following lines:
- MS BRE is part of a BizTalk Server, which is a business-oriented server package, while WF Rules is part of the free .NET Framework which is more developer-oriented. (MS BRE may be used standalone outside of BizTalk, but is only licensed with BizTalk.) Both engines provide forward chaining execution. WF Rules also provides the option for sequential execution.
- MS BRE rules are typically authored in the Rules Composer, while WF Rules are typically authored in Visual Studio. There are partners that provide a more BRMS-like authoring environment. MS BRE has features such as vocabularies and a respository, and is therefore closer to what Gartner defines as a BRMS.
- MS BRE implements the Rete algorithm, while WF Rules does not. MS BRE uses eager evaluation, while WF Rules uses lazy evaluation. The performance profiles are accordingly different – WF “first hit” execution being faster, for example.
- WF does not have assert/retract keywords or a Working Memory, while MS BRE does – so WF Rules requires all objects to be reachable from a common root object (this). (In WF Rules, support for multiple instances is achieved through forward chaining.) WF Rules supports “Else”, while MS BRE does not. MS BRE has some known restrictions around negation-as-failure. MS BRE has special handling for XML and DB fact types.
I would be remiss if I did not mention some Microsoft offerings that apply to related areas:
Lastly, I should also point out that the Mono Project is reimplementing Windows Workflow Foundation – including WF Rules.
January 11, 2010
Every so often I hear about a “friend of a friend” who has implemented a backward chaining project with one of the Microsoft rule engines (WF Rules, BizTalk MS BRE). However, the details usually fail to materialize. If you have worked on such a system, or know someone who has – please contact me using the contact form on this blog. I’m interested in understanding more about your project and how successfully the backward chaining implementation went.
(As always – this is mainly personal interest, and does not reflect on any future directions of my employer’s products.)
March 28, 2009
If you are running both BizTalk BRE and Windows Defender, you may want to note that the BizTalk 2006 R2 documentation at MSDN has been updated recently to take into account a recent interaction with Windows Defender. The issue with Windows Defender was corrected immediately, and the fix for affected machines is simply adding localhost back to the hosts file.
This is the 2006 R2 documentation, but I believe the issue could also affect 2004, 2006, and 2009 Beta.
December 6, 2008
Many thanks to those readers who participated in the Microsoft BizTalk BRE survey that Charles Young pointed to in his blog.
In the future, I will endeavor to link to such surveys from this blog as well.
Charles mentioned in his post that he would liked to have seen a more “forward looking” survey, but hasn’t (as yet) followed up with any clarifications.
If you missed the survey, or have comments regarding it – I would love to hear from you.
November 14, 2008
Since I have already linked to my employer once today, I might as well post this too.
There is a series of challenges involving the programming of simulated robots at our RoboChamps site. Working with simulated robots should be familiar to those of us who have worked with RoboCup (or the simulated version) or TankSoar. The challenges include such tasks as navigating a maze, driving in an urban environment, sumo wrestling against another robot, and more. A soccer challenge looks to be coming soon under the name “Tournament”.
Read the rest of this entry »