RE: [RIFRAF] Response to ACTION-179

This raises an interesting point: semantics vs syntax of target rule systems as far as RIF is concerned.

TIBCO's BusinessEvents is one of the more successful commercial CEP (Complex Event Processing) systems & uses a type of "ECA" rules, but rules are defined in terms of production rules (plus a state transition diagram). So in terms of representation (and interchange formats), production rules are sufficient for the rules, but not for the full semantics of CEP. Indeed, the execution semantics are slightly different from (ie an event-driven superset of) conventional Rete-based rule engines (ie PRR).  

So: Business Events rule language ~= PRR + event semantics

And: in terms of rule classifications/ontologies, the ECA rules used in TIBCO are in effect a specialization of PRR. As event mechanisms can be considered out of scope for RIF (in my opinion, as both the CEP world and organizations like OMG SOA are in the early stages of investigating this as I understand), full CEP rules are unlikely to be an early candidate for RIF interchange. 

Real world: supporting business rules (eg as supported in RIF/PRR format) *are* used to support CEP event rules, and are definitely a candidate for interchange to this CEP system.

Summary(theory): many ECA rules may be considered derivatives / specializations of production rules, with different semantics (ie event processing conditions and actions). For representation, they will be covered by the production rule representation extended to handle popular event tests and actions. However, as RIF will not encode event persistence data, the utility of RIF for some ECA systems (such as CEP) will be limited. Note there are no CEP use cases.

Paul Vincent
TIBCO - ETG/Business Rules 
 

-----Original Message-----
From: public-rif-wg-request@w3.org [mailto:public-rif-wg-request@w3.org] On Behalf Of Alex Kozlenkov
Sent: 21 November 2006 15:11
To: Paula-Lavinia Patranjan; Leora Morgenstern
Cc: public-rif-wg@w3.org
Subject: RE: [RIFRAF] Response to ACTION-179


Guys,

For reaction rules, there are two ongoing projects that could provide
ideas for ontology characterization.

One is the Reaction RuleML initiative:
	http://ibis.in.tum.de/research/ReactionRuleML/ . 

The other is REWERSE r3 prototype:
	http://rewerse.net/I5/r3/. 

In the first one, we have distinguished active vs. passive reaction
rules (essentially having to poll vs. reacting passively to pushed
inbound messages) functionality. We also orthogonally distinguish global
(non-contextual) and local (contextual) rules. In particular, the latter
allow the reactions to be contextualized by the current evolving state
of conversations making them comparable to process algebras, in
particular, pi-calculus.

Passive rules could be also categorized as message-based in that they
effectively capture communication acts explicitly. 

The REWERSE r3 prototype, also using the Prova language for the
conditions and actions part, is based on a developed r3-ontology. It
specifically distinguishes query and test components of an ECA rule.

In summary, these are the resources that perhaps we should consider
aligning the current RIFRAF view of the ECA area with.

Alex Kozlenkov
Betfair Ltd.

>>  -----Original Message-----
>>  From: public-rif-wg-request@w3.org
[mailto:public-rif-wg-request@w3.org] On
>>  Behalf Of Paula-Lavinia Patranjan
>>  Sent: 21 November 2006 12:28
>>  To: Leora Morgenstern
>>  Cc: public-rif-wg@w3.org
>>  Subject: [RIFRAF] Response to ACTION-179
>>  
>>  Hi Leora,
>>  
>>  This message is a response to the action we both took during the F2F
>>  meeting in Athens to revise and ontologize section 5 of RIFRAF (see
[1]
>>  for my action). I read the comments attached to the answers to
section
>>  5's questions and tried to determine whether new questions should be
>>  added to this section or refinements of the existing questions are
>>  desired. Below are some proposals for improving section 5 of the
>>  questionnaire.
>>  
>>  (New discriminator to be added to 5.1)
>>  What kind of rules are used for realizing the reactive behaviour?
>>    * Event-Condition-Action (ECA) rules
>>    * Event-Condition-Action-Postcondition (ECAP) rules
>>    * Production rules
>>    * Other (Please specify!)
>>  
>>  (Update of discriminator 5.1.2; add the possibility to answer with
>>  'Mixed' to the question)
>>  Are the different parts of a rule (e.g. Event, Condition, Action
parts
>>  for a ECA rule) clearly separated (separation of concerns)?
>>    * Yes
>>    * No
>>    * Mixed (some rules in the language follow such a separation of
>>  concerns, some not)
>>  
>>  The comments to the question 5.2.3 'Does the language support only
>>  atomic events or also composite events (combinations of more than
one
>>  event such as temporal or events)?' could be considered as basis for
a
>>  new discriminator for the (concrete) types of composite events
>>  supported. The problem is that there are two many possibilities for
such
>>  concrete composite events supported by a reactive language.
Moreover,
>>  the questionnaire already contains similar discriminators but more
>>  abstract (see 5.2.6 and 5.2.7). Thus, I propose not to add a new
>>  discriminator for types of composite events.
>>  
>>  What is your opinion on the proposals above?
>>  
>>  Best regards from Munich,
>>  Paula
>>  
>>  [1] http://www.w3.org/2005/rules/wg/track/actions/179
>>  
>>  
>>  
>>  
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Received on Tuesday, 21 November 2006 16:46:32 UTC