You’ve Built The Pieces, Now Integrate Your Enterprise!

Mid-Atlantic Regional ConferenceJanuary 17, 2003

Patty Gertz, Princeton UniversityPatty@princeton.edu

Copyright Patricia Gertz, 2003. This work is the intellectual property of the author. Permission is granted for this material to be shared for non-commercial, educational purposes, provided that this copyright appears on the reproduced materials

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Enterprise Application Integration

“Making independently designed application systems work together.”Gartner

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PeopleSoftHR

Labor Acctg

BlackboardCourseInfoBSR

Advance PeopleSoftStudent

Web/Portal Web Portal Web

======= Departmental business process ======

Why do we need this?

Applications are changing – not all in-house developed, many are purchased.

Customers are changing – larger, broader constituencies.

Services are changing – self-service, access through the web.

Web enablement vs. web development vs. web integration vs. web services.

Gartner says 35% of the IT budget in new projects will go to integration. We need to manage this.

Goals

To reconcile differences in data. To coordinate execution of logical

processes that span applications. To reuse parts of existing applications as

components of new ones. To be agile.

What do we gain?

A more flexible approach to automating business processes will make us more responsive. Typically interfaces are point to point,

separately designed and built. This has resulted in a new version of the

spaghetti diagrams we saw in the past.

New World Spaghetti Code

Integration Approaches

Technical – middleware, messaging, file transfer Data – db replication, directory services, common

data definitions and storage Business Process – think in terms of logical

business processes, even when they cross the line of a particular application

User Interface – the web and portals can unify the enterprise. Layering apps so you control the presentation.

Addressing IS Heterogeneity

Three approaches:– Rip out and replace – Wrap or re-engineer – Leave and layer

Rip and Replace

“Bulldoze the slums.” Replacing with a new set of consistent

applications (ex. ERPs) Easy interoperability, reuse, common data. Business reality often makes this not

possible.

Wrap or Re-engineer

Wrapping masks the problem of heterogeneity.

Re-engineering changes the apps to conform to new standards.

Technically hard, good for new, component-based apps.

Service Oriented Architecture– Web services, WSDL, XML

Leave and Layer

City Planning vs. Architecture Leave underlying systems alone, and

understand change will always happen in that layer

Use file transfer, messaging, shared databases, for information exchange.

Architecting an Integrated Enterprise

Enterprise architecture describes the underlying distributed computing infrastructure.

It helps us manage the impacts of changes. Applications must deal with changes in business processes from above, and changes in technology from below.

Equally good for new development and integration.

Service Oriented Architecture

Qualities of a Good Architecture

Adapt to change Flexible Good performance Scalability Security Manageability Reliability Portability No vendor lock-in

What’s Different About Web Applications?

State Authentication / Authorization Scalability and Performance - Pooling

and sharing of resources Commit / Rollback, even with multiple

targets

Application Layers : Standard 3-Tier

Desktop Presentation and GUI Layer-User interface, presentation, navigation-Invokes business rules and processes

Business Rule and Process Layer-Accepts processing requests from desktop-Implements university policies and procedures-Implements rules and supports business processes-Requests data from databases

Database and Data Management Layer-Provides data to business layer-Ensures data security, consistency, integrity, and safety-Usually outside application development scope

Desktop PresentationLogic

Business Rules andProcessing Logic

Database and Data Management Logic

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Application Architecture: New Model

Application Architecture - Multi-tier, message passing, distributed

"fat infrastructure" Characteristics

- logical separation of layers - ability to flexibly configure physical

layers as needed - access to shared infrastructure

Architecture Issues - enterprise infrastructure management

Desktop Presentation

Logic

Database and Data Mgt

Logic

Business Rules and Processing

Logic

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J2EE and Component Based ArchitectureWhat Services does it offer?

Standardized modular components/reuse

Connection sharing - multithreading Static and dynamic web pages Messaging Database Resource pooling Platform independence

Getting Started

People must be in a separate group – can’t be associated with a specific project.

Management Support – someone has to be convinced it’s worth extra resources.

Global view – step back and architect. Skills – Object orientation, components, J2EE

or .Net The sooner you get started, the less you have to

undo.