bpmn in pegasystems prpc flow rules

BPMN in PegasystemsPRPC Flow Rules

by Declan Chellar@AnalysisFu

Pega BPMN: the perception

There is a perception that Pegasystems PRPC can be used to create BPMN-compliant process models.*

* This slide deck is relevant up to PRPC version 6.2.

What the Pega Developers Network says

“BPMN stencil — By selecting a BPMN Visio stencil, you can create flow diagrams that closely match the appearance and notation used in Business Process Management Notation (BPMN) diagrams.”*

* http://pdn.pega.com/Devnet/Announcements/Announce61/process.asp




Notice the words “closely match”.This is not the same as saying that Pega’s BPMN stencil is BPMN-compliant.




Notice the words “closely match”.This is not the same as saying that Pega’s BPMN stencil is BPMN-compliant.

CAVEAT:Pega does not claim that “Pega BPMN”

Flow Rules are BPMN-complaint.

A sub-process expressed using BPMN

• The next slide contains an example of a sub-process modelled using BPMN.

• This sub-process “Review Leave Request” is part of a higher-level workflow for handling leave requests.

• That workflow consists of three sub-processes:• Request Leave• Review Leave Request• Review Rejected Leave Request.

• The level of modelling on this diagram calls out all the logical steps that need to take place in order to review a leave request.

• Details such as data requirements and business rules do not appear on the diagram, although steps where business rules get invoked are indicated.

A sub-process expressed using BPMN

The sub-process as implemented by a Flow Rule

Here we see how an initial draft of the PRPC Flow Rule for “Review Leave Request” might look.

This diagram shows Pega Standard shapes.

The same Flow Rule in Pega’s version of BPMN

And here we see how the initial draft of the PRPC Flow Rule might look using Pega’s version of BPMN shapes.

Compare the levels of visible detail


Both are supposed to be BPMN models of the sub-process


Pega Developers Network says: “BPMN stencil — By selecting a BPMN Visio stencil, you can create flow diagrams that closely match the appearance and notation used in Business Process Management Notation (BPMN) diagrams.”


BPMN is a standard modelling notation maintained by the Object Management Group.


A BPMN modelling tool is either BPMN-compliant or it is not. Closely matching is not compliance.


Moreover, the diagram on the right does not closely match the one on the left.


BPMN-trained business stakeholders would understand the diagram on the left, but would be confused by the lack of BPMN-compliance in the Flow Rule on the right.


It would be better to show business stakeholders a Pega Standard Flow Rule and get them used to the Pega

Standard notation.

Pega BPMN is just a way of “re-decorating” Flow Rules

The Pega Standard notation is on the left and Pega BPMN on the right.


All Pega does is “re-paint” its Flow Rule shapes to look like BPMN shapes.


This is not the same as BPMN-compliance.


PRPC Flow Rules implement the business process and as design/implementation devices, they do not make all the

necessary business steps explicit on the Flow.

Much of the logical detail is not explicit in the Flow Rule

This slide highlights business process steps which are unlikely to be explicit on the Flow Rule, even though they

are handled by Rules “behind” the Flow.


From a business stakeholder perspective , the Flow diagram does not fully represent the business process.


However, a Flow Rule is not meant to illustrate the business process, rather its implementation.


But you should not try to use your Flow Rule to express something which it cannot.

Pega BPMN is not BPMN compliant


The Integration shape that Pega uses on the “BPMN” view of the Flow is not part of the BPMN palette.


In BPMN “diamond” shapes are known as “Gateways” and serve only as visual aids in navigating the diagram. No

processing takes place inside a Gateway.


Instead, in BPMN, business rules are invoked and executed inside a task shape.


In PRPC’s version of BPMN, there is behaviour going on inside “diamond” shapes, which breaks the rules of BPMN.


Although it is correct from a PRPC perspective to hide process details behind Flow Rule shapes, from a BPMN

perspective, this is not correct.

Further limitations to Pega BPMN

• Pega BPMN cannot and should not include manual steps. BPMN can and should.

• Pega BPMN cannot and should not include steps and sub-processes executed in non PRPC systems. BPMN can and should.

• Pega BPMN cannot and should not include steps and sub-processes which are out of scope for the current software implementation. BPMN can and should.

• BPMN is technology-agnostic; Pega BPMN is technology-specific.

Conclusion

• The Pega BPMN stencil is not a tool for creating BPMN models within PRPC.

• It is a way of viewing PRPC Flow Rules using shapes reminiscent of BPMN.

• Pega BPMN is not BPMN-compliant.• This non-compliance is likely to confuse

stakeholders who are BPMN-trained.• Better to get stakeholders used to Pega Standard

Flow Rules.

Conclusion

In golf, no matter how good your 3-iron is, you can’t turn it into an 8-iron by scratching on the number.

www.chellar.com/AnalysisFu

bpmn in pegasystems prpc flow rules

Technology

pega developers

words closely

decorating

bpmn visio

flow rule

create flow

pega standard

pegas bpmn