enterprise application integration an architecture for integration

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Enterprise Application Integration An architecture for integration

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Enterprise Application Integration

An architecture for integration

Structure of enterprise applications• Enterprise Applications “should” keep track of (data) information

related to the operations of the enterprise– e.g. Inventory, sales ledger

• And execute the core business processes that create and manipulate this information– Process from ordering of products to cash received

• Enterprise may also have supply chain management systems or customer relations managements systems which also requires keeping track of information from outside the organisation

• Data in the organisation is captured in a number of data models: relational data model; star scheme….

Example of the steps in a business process: “The purchase order process …”

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Purchase and payment process

• 1: Presales activity– Determine requirements and complete purchase

requisition.

– Based on:

• quantity on-hand,

• quantity-on-order, a

• expected demand.

– What applications may be used to generate this data

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Purchase and payment process

• 2: Prepare and record purchase order.– Receive the purchase order requisition then – Assist in identifying sources of supply for the

requested item, analyzing vendor quotes,• comparing vendor prices, terms, and past performance

• 3. Receive and record goods.– Compare quantity ordered to quantity received. – Routes goods to the function that requested them

or directs them the warehouse for immediate sale. It also records vendor performance data.

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Purchase and payment process

• 4: Receive vendor invoice, match with purchase order and receiving report; record payable.– If the three-way match fails, the enterprise system

notifies the proper personnel to ensure timely reconciliation of differences.

• 5. Prepare and record cash payment and update accounts.– Uses vendor and account payment data to schedule

payments in accordance with terms of sales agreement.

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Enterprise process models

• Each business process model “must” capture the series of steps and interactions required to complete a specific business process: – The execution of the process will impact on the enterprise data across

one or more applications– A process may be executed within a single application or more often

through collaboration between several applications

• In the semi-automated (Islands of computing) system: – Originally, the process and data models were implemented in a wide

variety of functional system (related to organisational departments)– Each system consisting of its own database, application logic and user

interface

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IT reality – Islands of Computing

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Purchased Application Package(s) – etc.

New Web-based

application(s)

Legacy Application System(s)

ProgramProgram

Program

ProgramProgram

Program

ProgramProgram

Program

Enterprise IT reflects the structure and history of each enterprise not the business processes required. Departments have their own IT systems Legacy systems are left in place and new systems built

separately.

Two architectural solutionsSolution 1:Integration• Leave existing applications in place

– Minimises risk of disruption and change in data models/process models

• Link existing applications, integration of systems, which map between existing data and process models and add ‘missing’ process models where required

• Effective when most of the functionality is already implemented in systems and the integration is primarily creating linkages and processes between these applications

• When significant additional functionality is required beyond what is already in the applications,: may need to replace existing systems or redesign the data (inconsistencies) and business process models

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Tactical approach to integrating the Business information systems

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ProgramProgram

Program

ProgramProgram

Program

ProgramProgram

Program

LoadProgram

ExtractProgram

ExtractProgram

LoadProgram

ExtractProgram Load

ProgramScreenScrape

Database Replicator

DownloadFile

DownloadFile

TransactionFile

MessageQueue

DownloadFile

TransactionFile

MessageQueue

ApplicationSystem B

ApplicationSystem A

ApplicationSystem C

Each requirement is addressed with a point to point solution Typically consisting of a data transfer mechanism and a data

format converter.

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Strengths Focused on getting the job done Each individual solution can be created quickly

Technical Weaknesses• Numerous Point-to-Point Interfaces• Sharing of data between systems

• Data duplication• Data inconsistency

• Inconsistent Qualities of Service• Limited or lack of integrated information

Inconsistent Business Processes solutions as they are not integrated

Strengths and weaknesses of “islands of Computing” tactical approach

Strengths and weaknesses of “islands of Computing” tactical approach

Business Weaknesses– Cost of maintenance– Isolated decisions lead to overall inefficiencies

• Increased expenses– Requirement to retain knowledge of the solution in-house.– Potential security or loss of service/process failure due to

inconsistencies.

• Therefore, there is a general requirement for integration to support organisational system capabilities– For instance Customer Relationship Management – tracking

all information about a customer across the enterprise12

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Solution 2: Enterprise “information systems” integration

EAI can help resolve the following issues:

Unrestricted sharing of data and business processes (information) across an organization and can be extend to customers, suppliers and regulators

The linking of data, business processes and applications to automate business processes While ensuring that there are consistent qualities of

service (security, reliability etc)

Reduce the on-going cost of maintenance and reduce the cost of rolling out new systems.

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The ideal integration of enterprises applications Unrestricted sharing of data and business processes

throughout the networked applications or data sources in an organization

The Linking of Data, Business Processes and Applications to automate business processes

• ensuring that there are consistent qualities of service (security, reliability etc)

Reduce the on-going cost of maintenance and reduce the cost of rolling out new systems.

Devised ways to efficiently reuse legacy and existing apps and add new ones

A solution is referred to as: Enterprise Application Integration

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Layers of an EAI Stack

EAI

Data Transformation

Business Activity Monitoring

Message Storage & Routing

Business ProcessOrchestration

AdapterAdapter

Provides real-time and historical data on performanceof processes and assists in making decisions.

Manages and tracks business transactions that mightspan multiple systems and last minutes to days.

Ensures the data is the correct format for delivery to The next system.

Provides “open” connectivity between data sources: programs that interact with the underlying business application

Ensures the reliability of data delivery between systems.

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Adapters

Data Transformation

Message Storage & Routing

Business ProcessOrchestration

Also known as “Connectors”, “Translators”, “Wrappers” or “Bridges”

Provide seamless connectivity to the underlying application or data

Converts data into “information and events” (a form) that can be utilized by the “enterprise’s” I.T. infrastructure

AdapterAdapter

Business Activity Monitoring

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Reliable messaging Connect applications running on different

systems by sending and receiving application data as messages

1 Message storage Central repository for temporary storage of

transactions until they can be delivered Also called “Message Warehousing”

2 Message queuing and routing Asynchronous communications Set of tools that route messages between

sources and destination (consumers) based on pre-defined “business” rules

Message storage and routing

EAI

Data Transformation

Business ProcessOrchestration

AdapterAdapter

Message Storage & Routing

Business Activity Monitoring

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Data Transformation

Transformation to and from formats used by Different Systems

Handling simple or complex data structures

GUI Configuration tools to help define the transformations

Data Transformation

EAI

Data Transformation

Business ProcessOrchestration

AdapterAdapter

Message Storage & Routing

Business Activity Monitoring

Data Transformation

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EAI typically converts the source data into an intermediate format and then convert its into the target format .

Source Target

F. name: denisL. name: manleyAffiliation: DIT, Dublin,Ireland

Name: Denis ManleyCompany: DITCity: DublinCountry: Ireland

Intermediate (canonical)

common format

EAI: Building a data model

• Create a common data model including a set of terms for the concepts in the domain of the data sources being integrated– e.g., Employee, Customer, Patient, weight, height, body Temperature,

• Mappings relate data items in data sources to terms in data model

• Background knowledge about terms essential for transformations – e.g., Employee subClass Of Person, – 2 people with the same last name, first name and street address are

likely to be the same,

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Some Issues in data transformation

• Challenge 1: Coping with software from different vendors– Oracle vs. SQL Server

• Challenge 2: Coping with different “data” formats– Relational vs. XML

• Challenge 3: Coping with data from new sources such as new systems, suppliers, customers

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Process Modeling Describing the flow of information in the

context of business processes Using the input/output of processes as the

Integration points between diverse business processes

Process Brokering Execution of discrete steps within a

business process Ability to recover from failed steps

Process Management Monitor business processes Correlate metrics to specific business

process steps

Business Process Orchestration

EAI

Data Transformation

Business ProcessOrchestration

AdapterAdapter

Message Storage & Routing

Business Activity Monitoring

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Business Activity Monitoring

EAI

Data Transformation

Business ProcessOrchestration

AdapterAdapter

Message Storage & Routing

Business Activity Monitoring: Using your data assets (sales figures) to make better decisions

BAM is used to gather information about what is occurring in the EAI deployment Status of current processes Identification of problem areas

E.g. Spotting applications that are not responding

Monitoring of unusual activity E.g. Unusually large orders

The collected information is displayed for operators or managers to diagnose and determine the solution

Business Activity Monitoring

Potential EAI benefits

• Lower costs– Integration is simpler because systems are more loosely coupled. – Integration is done more quickly– corresponding cost savings reachieved sooner

• Lower maintenance effort– adapters extract the interaction with external systems– significant advantage from the software engineering point of view

• Increased Information sharing:– reduces data duplication and data inconsistencies; e.g. Only some systems not need to

collect the data which is shared with others in the system• Streamline of processes including data and software: reducing

inconsistencies in the business process

• Increased integration of business processes – increase business agility; responding to shifts in the supply chain (maybe acquire a new

supplier)

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Potential EAI Challenges• Architecture concentrates all of the processing into a single server/cluster.

– Often became hard to maintain and evolve efficiently– Hard to extend to integrate 3rd parties on other technology platforms

• The data transformation model introduces an intermediary step– Added complexity and additional processing effort

• EAI products typified by– Heavy customisation required to implement the solution– Lock-In: Often built using proprietary technology (specific to a vendor) and

required specialist skills – Lack of flexibility: Hard to extend or to integrate with other EAI products!

• Requires organisations to be ready or prepared to adapt EAI: EAI readiness

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What is EAI readiness? Much of the challenge associated with adopting EAI is not

related to the technology but to how prepared the organisation is to implementing it.

EAI readiness is a state of business maturity in which the enterprise’s:

1. Business processes, 2. employees,3. Technology (systems) 4. structure, 5. and culture,

are prepared for the successful introduction of both EAI technology and the business disciplines that drive its introduction.

All five of these factors must be properly situated and aligned before an EAI implementation can succeed.

Business process readiness Business strategic goals for project (i.e. process efficiency,

customer satisfaction, supply-chain optimization) clearly defined and agreed upon by company executive leadership.

Desired business processes designed, documented, and valuated.

Gap between current and desired business processes well understood.

Employee readiness Staff accustomed to using information technology in their

day-to-day work.

Staff accustomed to adaptation of new roles, responsibilities, processes, and knowledge … ; i.e. to business change.

Staff have broad understanding of the business and their contribution to it.

Executives understand the nature of investing time, staff and budgets into the business infrastructure in order to reap future returns. (financial v strategic)

Technology readiness

No systems are to be integrated using EAI tools that will be retired/ decommissioning soon. There is no point integrating with a system which will soon be

removed

Applications portfolio has been evaluated for semantic compatibility. Check it is possible to transform from 1 data model to the other

Implementation of EAI is not defined as the purpose of the effort. The project should be about the business objective, not about the

technology

“Organisational” Structural readiness

Keep it simple by ensuring that the EAI system involves as few departments/ organisations as possible. Each organisation involved adds to the complexity of the

project as more people have to be engaged with and there are potentially greater variety of technologies and architectures.

Stakeholder analysis performed to determine overall potential for business resistance to the planned change. EAI projects change the way that each

department/organisation works. Therefore, EAI projects need the cooperation of each department/organisations.

Business “steering” committee is established and ready to provide leadership to the business change.

Cultural readiness

Corporate culture embraces the importance of well-defined business processes.

Staff accustomed to adaptation of new roles, responsibilities, processes, and knowledge ….

Individuals and departments willing to change the way the applications and data is defined.

Questions• Many technologies involved in business difference business process

can not effectively communicate and share data. Enterprise application integration is one approach to ensure limiting this problem:

• Describe the 4 “main” steps in the EAI framework• (12 marks)

• Explain, using a suitable example, why EAI is preferred to the to the “islands of computing” and the tactical approach to developing enterprise I.T. systems.

• (8 marks)

• Discuss why an organisation must be prepared in order to correctly implement the EAI approach.

• (10 marks)32

Questions• Explain, using a simple example, the steps

involved in a business process (6 marks).

• Distinguish between the tactical approach and the enterprise application integration (EAI) approach to the integration of an organisation’s information systems. (8 marks)

• Explain how any three of the steps in the E.A.I. framework help it overcome the limitations of the tactical approach (16 marks)

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