The Whys of Oracle SOA V2

The "Whys" of Oracle SOA

Chris OstrowskiFujitsu America, Inc.

The "Whys" of Oracle SOAAuthor’s Websites

Company Website:http://www.fujitsu.com

Author’s Website:http://fourthmonth.wordpress.com/

The "Whys" of Oracle SOATopics

Topics discussed:– Introduction– Why SOA?

• A brief history of n-tier architecture

– Why do Web Services exist?– Why does the Service Bus exist?– Why is XML everywhere?– Why is there a rules engine?– Why is everyone talking about the “cloud”?– Summary

The "Whys" of Oracle SOA Introduction

Introduction

The "Whys" of Oracle SOA Introduction

Why ask why?• You already know the “What?” and the

“Who?”• Google is great for the “How?”• Answering the question: “Why?” - tough•With SOA, a *lot* of “Whys?” will have to

be answered

The "Whys" of Oracle SOA Why SOA?

Why SOA?


Brief history of n-tier architecturePhase 1: Server <-> Dumb TerminalPhase 2: Server <-> PC (Client/Server)Phase 3: Server <-> Web Server <-> Client (n-

tier architecture)Phase 4: Distributed computing (here’s where

SOA comes in)


Web Services – a black box of functionality

Composite applications – like a jigsaw puzzle of web services


Companies need to be agile

Systems need to be agile

Systems need to support the business

SOA is a philosophy, not a product


Functionality “exposed” through web services

How to manage and monitor exposed services?

How to integrate internal and external services into applications?

How can code and functionality be re-used?

SOA!


Example: Retailer does credit checks on large vendors and wants to use that functionality for customers. Instead of re-inventing the wheel (and having multiple credit-check code procedures to maintain), credit check procedure is exposed as a web service – credit checks against vendors in one program and credit checks against individuals in another program use same code base to handle approval process

The "Whys" of Oracle SOA Web Services

Why do Web Services exist?


Technology that enabled the internet as we know it: TCP/IP

Technology that enables distributed computing: Web Services


Uses XML to exchange info with other software using common protocols

Encapsulates a specific taskUses XMLSelf-describingDiscoverable


Competing technologies:CORBADCOMRMI

Key differentiators: Web Services work over HTTP – eliminates many firewall issuesLingua franca: XMLComposite apps can use web services developed on any platform in any language

The "Whys" of Oracle SOA The Service Bus

Why does the Service Bus exist?


SOA and web services are based on “messages”

Web Services are de-coupledESB provides a common framework to

handle Web Services messages without forcing them to be coupled

The ESB hides details in proxies


Example: Hospital uses a program that uses a web service to interact with insurance company “X”. “X” gets bought by “Y” who has their own web service. Instead of writing a new program for “Y”, web service in ESB can be modified for “Y” without changing client application.


Communications Nerve CenterServices:

MessagingPoint-to-pointPoint-to-point request/responseBroadcastBroadcast request/responsePublish/subscribeStore and forward



ManagementInterface

Adapters - ESB routes message to an app and has to transform message into a format that the app can interpret. A software “adapter” fulfills this taskMediation

Service Broker – facilitates interaction between partners



MetadataSecurity

AuthenticationAuthorizationPrivacyIntegrityAuditing

Service Abstraction


Core functionality:Invocation support for synchronous and asynchronous

transport protocols, service mapping (locating and binding)

Routing addressability, static/deterministic routing, content-based routing, rules-based routing, policy-based routing

Mediation adapters, protocol transformation, service mapping

Messaging message-processing, message transformation and message enhancement


Core functionality:Process choreography implementation of complex

business processesService orchestration coordination of multiple

implementation services exposed as a single, aggregate service

Complex event processing event-interpretation, correlation, pattern-matching

Other quality of service security (encryption and signing), reliable delivery, transaction management

Management monitoring, audit, logging, metering, admin console, BAM


Core functionality:VETRO

ValidateEnrich (Invoke a web service, query a DB, etc)Transform (XQuery)RouteOperate (Primary function – deliver the message)

The "Whys" of Oracle SOA XML

•Why is XML everywhere?


6,000 human languages8,000 computer languagesHow are programs supposed to interact

with other programs?


Standard needed that’s extensibleXML describes data itself, not just how

to display itSource program not only sends data, but

also sends “what” it’s sending

The "Whys" of Oracle SOA The Rules Engine

Why is there a rules engine?


Typical enhancement request:1) User identifies need(s)2) Business analyst outlines change3) Developer must locate change and implement4) Unit test for validity5) Integration test6) System Test7) Regression test8) Acceptance test9) Deployment


Typical enhancement request with a rules engine:

1) User identifies need(s)2) Business analyst makes change in

rules engine


Example: Retailer grants $500,000 in credit to large vendors. In Q4 (anticipating greater volume for holiday season), retailer temporarily grants $750,000 in credit to large vendors. With rules engine, business analyst can make change “on-the-fly”.

The "Whys" of Oracle SOA The Cloud

•Why is everyone talking about the “cloud”?


Most developers/IT personnel do a lousy job estimating (even with years of experience)

Cloud technologies allow you to “spin up” additional hardware/computing power as it’s needed


If SOA is in place, expanding capabilities of complex applications distributed amongst a (potentially) infinite number of servers is relatively simple

Redundancy and 24/7 access is more easily obtained

The "Whys" of Oracle SOA Questions?

The "Whys" of Oracle SOA Where to get more information

Fujitsu:http://www.fujitsu.com

Oracle documentation:http://docs.oracle.com

Author’s Website: http://fourthmonth.wordpress.com/

Author’s Email:[email protected]

Contact Information

Phone: (303) 908-5115http://www.fujitsu.com

Please report errors to author. Neither Fujitsu, Oracle or the author warrant that this document is error-free.Fujitsu © 2011. This document may not be copied or reproduced without the express written consent of Fujitsu America, Inc..

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The Whys of Oracle SOA V2