Simulating Enterprise Architecture Models

MIDDLESEX UNIVERSITYLONDON | DUBAI | MAURITIUS


Simulating Enterprise Architecture ModelsBalbir S. Barn, Tony Clark (Middlesex University) and Samia OussenaUniversity of West London)

ISEC 2012, Kanpur, February 2012


Agenda

• Problems with Enterprise Architecture (EA)

• EA overview and related work

• Concepts for a light-weight method for EA

• The EA method• Case study

• Conclusions


EA overview (definitions and use cases)

• “it is a coherent whole of principles, methods, and models that are used in the design and realization of an enterprise’s organizational structure, business processes, information systems and infrastructure” (Lankhorst et al)

• The uses of EA include:– alignment between business functions and IT systems– business change describing the current state of a

business (as-is) and a desired state of a business (to-be)– Ensuring quality (e.g. security, performance)– Acquisition and merger planning– Regulatory compliance


EA overview (2)

• Origins in Zachman’s Framework (1999)

• Today often described by large fulsome frameworks such as: TOGAF, DODAF, FEAF

• Accompanying methods are proprietary (e.g. ORACLE, IBM)

• Some emerging DSLs for EA– Notably Archimate (ref): concepts and supporting

notation


A missing piece

• How does an EA change to meet a new business requirement?– What impact on what systems? – Support for an equivalence analysis needed

• The current methods and frameworks use layered architectures and do not readily support this type of analysis

• Existing emphasis on SOA as an architectural style

Simulation: Try it and see. A means for meaningful human intervention


Combining SOA with Event driven architecture

• Service Oriented Architecture (SOA)– Publication of functionality as interfaces– Interface usage via components (asynchronous/synchronous)

• Event driven architecture (EDA)– Components are event generators and consumers (reduced

coupling)– Scope for Complex Event Processing (business processes

triggered by multiple, possibly temporally related events.

• Combining both approaches provides greater expressivity for dealing with a complex domain such as EA

• This paper addresses the method requirements for this combined approach


Key features of the language


Model Requirements Define Logical EA

Collate Physical Architecture

Define Physical EA

Define Conformance and Simulate

Configure Physical Architecture

To

be A

nalys

isA

s Is An

alysis

New DSL Technology incorporating:Integrated model for services, events and simulation

Utilize established techniques such as CRC, Use Case Models, Use Case Maps, UML …

Business use case model; Information model;

Business process model;Context Diagram

Current components

Candidate Physical EA

Candidate Logical

Components

Simulation Logical EA(Components,

Interfaces, Events)

Refined Logical EA

Simulation Physical EA

Scope phase

Simulate phase

Candidate Physical EA

Step 1:

Step 2:

Step 3: Step

5:

Step 6:

Method Overview

• Existing methods are:– Large, cumbersome, lacking in agility and precision.

• The LEAP Method:– Has two streams for “as is” / “to be” modelling– Utilises existing, best of breed modelling techniques

Step 4:


Case study

• UK Gov requirements on HE Institutions

• Provision of key information to help students make decisions on choice of university to study


Step 1: Model Requirements

• Use existing techniques such as those from Catalysis [ref], RUP and Ould [ref] to produce models such as:– Context models– Information Models– Component Specifications


Step 2: Define Logical Enterprise Architecture (L-EA)

• A key feature of our approach is to simulate both a logical and physical EA in terms of components, operations and events.

• Simulation language implemented as Java interpreter• Components monitor events raised

by registered components• Components maintain private

state (terms – named records)• Invariants are boolean expressions

defined over the state• Operations implement business

processes• Rules: a collection of patterns

that match terms and events. When all the patterns are matched the rules fire.

• The body of the rule is an action that modifies state or invokes operations


Step 2 cont’d: The University component

State

RulesInvariants


Using Simulation

Our LEAP language that supports the method also include features for generating a GUI on a web browser

The Control section is used to step through the simulation by sending tick messages to the clock


Using Simulation


Step 3, 4: Collating and Configuring Physical EA

• Use of existing system overviews to identify organisational systems

• Configuring a Physical EA involves taking an appropriate slice of the EA to that includes just those systems that are likely to be required by the “to be” requirements– Techniques such as Use Case Maps can be

used.


Step 5: Define Physical EA

Identified slices of the required components are expressed in LEAP


Step 6: Conformance

• Our EA design method produces:– A context, logical and physical EA using the LEAP

language• A single unifying language provides the means to

establish conformance between logical and physical models

• The language can be used to support techniques such as:– Inspection based approaches– Mappings between physical and logical models– Simulation– Model checking and theorem proving


Conclusion

• Enterprise Architecture remains a confusing and constantly evolving collection of expansive methods and frameworks that are document based

• This paper has presented an effort to address the core use case “managing change and impact assessment”

• Our effort includes:– A Lightweight method utilising existing techniques– An accompanying language that supports precise

specifications of “as is” and “to be” models– A simulation environment for supporting meaningful

human intervention


Research areas in MDSE@mdx

Model driven software engineering

User Modelling

EnterpriseArchitecture

Complex Events and

Big Data

Tool Modelling

Modelling for Theory Building

Methodology

Events

Foundations

Tools and Technologies: DSL Building Tools: XModeller


World Skills 2011: UK Prime Minister David Cameron

• Product Design Engineering students

• UK Skills Gold Winners• Euroskills Bronze Winners• Balbir/WorldSkills London 2011.m4v

Simulating Enterprise Architecture Models

Technology

Transcript of Simulating Enterprise Architecture Models