Service Oriented Architecture

Concepts, Principles, Facts, Myths, Hype, Reality…Part 1

Adomas SvirskasVilnius UniversitySeptember 2005

Agenda

• SOA as a moving target

• SOA from corporate point of view

• BEA SOA Domain Model and Strategy

• SOA from technical point of view

SOA is…

• The latest fashion in IT architecture• “SOA represents the biggest change in enterprise IT

since the advent of the Internet.” Infoworld SOA Executive Forum

• "Service-Oriented Architecture is an IT strategy that organizes the discrete functions contained in enterprise applications into interoperable, standards-based services that can be combined and reused quickly to meet business needs.“ Bill Roth, BEA Systems

• “SOA is a specific architectural style that is concerned with loose coupling and dynamic binding between services” [5]

SOA is...

…a new approach to developing applications [4]

SOA Benefits (Promised) [6]

• Allows IT to deliver services faster and align closer with business

• Leverage existing assets• Improved productivity, agility and speed for Business &

IT• Reduced development times and costs through re-use• Decreased integration costs and risks• Lower maintenance costs and higher data integrity• Allows business to respond quicker and deliver

enhanced user experience• Enables new ways to relate to employees, partners and

customers

SOA Expectations [4]

Q: What are the critical business or IT problems your company hopes to address using SOA?

Base: 261 respondents (those personally involved with SOA in their company)

24%

26%

35%

53%

59%

42%

42%

45%

47%

58%

59%

63%

46%

0% 10% 20% 30% 40% 50% 60% 70%

More effective use of external service providers

Customer service initiatives

Enterprise portal initiatives

Composite applications

Custom application development

More effective integration with business partners

Data integration

Integration to existing applications

Business process implementation

More flexible architecture

Employee self service

Streamlined supply chain

Global sourcing

Tech points of pain

Business pointsof pain

Source – BEA sponsored research with InfoWorld, [4]

SOA Roots

• SOA has emerged as a consequence of business and IT drivers of the past decade

• Business factors– Outsourcing of non-core operations– Business process re-engineering

• IT factors– Importance of universal middleware– The Internet

SOA from Business Perspective

• Business processes (BP) of any company prescribe how products are manufactured and offered to the clients

• Speed of change in BP domain corresponds to the speed of change in product offers, i.e. affects chances of survival in highly dynamic markets

• Flexibility is reflection of company’s ability to adapt its BPs quickly

The Services

• The business partners offer their resources in the form of services

• A service is:– Some sort of publicised package of

functionality– Composable– Discoverable based on describing metadata– Usable by a mutually agreed contract

The Services Taxonomy

• Component services: Simple atomic services potentially acting on single enterprise resource (e.g., database, code, etc)

• Data services: Service providing data querying, combination and transformation for multiple data sources.

• Business services: Atomic services composed of combinations of component services and rules.

• Workflow services: Long lived business processes coordinating other services with external interactions

Virtual Enterprises (Organisations)

• The need for speed and flexibility forces to outsource parts of the business, find the best partners on demand and manage a network of collaborations

• A company becomes a virtual organisation in its essence

• Mergers/acquisitions also create VOs• Complex VOs are tricky to manage and

operate without suitable framework

Virtual Enterprises (Organisations)

• VOs can exist inside a large company as well as cross company boundaries

• The partners inside a VO have no direct authority to control each other, as a rule

• The partners offer their resources (forms vary greatly) to other partners

• The collaborations between the partners include a number of business transactions

• The partners are loosely coupled

VO Lifecycle

Identification

OpportunityIdentification

OpportunitySelection

Formation

PartnerIdentification

PartnetSelection

PartnershipSelection

Operation

Design

FinancialManagement

Marketing

Design

Marketing

Termination

OperationTermination

AssetDispersal

To Function Well SOA Needs…

Service Infrastructure

Meta-dataRepository

Service Registry

Management

MessagingServices

MonitoringServices

DataServices

SecurityServices

UserInteraction

Services

BusinessProcessServices

CompositionTools

WebApp

Presentation Logic

ApplicationClient

Browser

Clients

Databases

Mainframes

Data

Legacy App

Identity/Policy

Portal

WSRP

WSRP

WebServicesWebServices

Data Layer

Data

Identity/Policy

Data

Data

Data

Process

Process

Process WebServicesWeb

ServicesMobile

… an infrastructure [4]

SOA Infrastructure

User Interaction

Inte

gra

ted

Co

mp

osi

tio

n E

nvi

ron

men

t

Security Services

Data and Information Integration

Message Services

Process Orchestration

Message Services Service Manager Service Manager

Message ManagementMessage Management Service RegistryService Registry

Security ServicesFederated Identity ManagementFederated Identity Management

Distributed Application Security ManagementDistributed Application Security Management

User InteractionPortal Portal

Multi-channelMulti-channel

CollaborationCollaboration

Interaction ManagementInteraction Management

Mon

itor

Com

pose

Prev

iew

Inte

gra

ted

Co

mp

osi

tio

n E

nv

iro

nm

en

t

Upd

ate

Process Orchestration

Business Process Management

Business Process Management

Business Activity ManagementBusiness Activity Management

Enterprise ConnectivityEnterprise Connectivity

Business RulesBusiness Rules

Business IntelligenceBusiness Intelligence

Composite Data ManagementComposite Data Management

Data and Information Services

Unified Meta Data RepositoryUnified Meta Data Repository Unified Data ModelingUnified Data Modeling

more details [4]

SOA Solution Components [3]

• Producers: A producer is an entity that offers a specific service or functionality

• Consumers: A consumer is an entity that makes use of the service offered by the producer

• Services: A service is an entity that performs a specific task when invoked

• Contract: A contract or an interface specifies a format in which the data needs to be provided to the service to perform the specific task

• Repository: A repository is a glorified version of a registry and includes the metadata relevant for the solution, namely service, service contract, data/object model, and so on

SOA in IT Context

From Paul Lipton, Web Services Journal, August 2005

Governance

• Governance is the management of development artefacts (or assets), such as Java code, HTML, XML, deployment descriptors, WSDL, etc.

• Governance is primarily about tracking and controlling development artifacts through their life cycles; from creation to archiving (it is usually not a good idea to destroy an artefact).

Debunking SOA Myths [3]

• Myth #1: SOA is a solution (panacea, silver bullet) to all software problems

• Myth #2: SOA is like a product, and can be downloaded for trial

• Myth #3: SOA is a complete, off-the-shelf solution

• Myth #4: SOA software always needs to be developed using Web services

Debunking SOA Myths [3]

• Myth #5: Any software development using Web services is aligned with SOA

• Myth #6: Each service is always atomic in nature

• Myth #7: SOA is not aligned with any standards

• Myth #8: SOA is the same as EAI

• Myth #9: SOA is a very expensive solution

Debunking SOA Myths [3]

• Myth #10: SOA solution components (services, contracts) are completely reusable

• Myth #11: Services in the context of SOA are not explicit

• Myth #12: SOA is applicable only to specific industrial domains

• Myth #13: SOA can be sold to customers as is

Conclusions

• SOA has many shapes and forms

• Domain Models, patterns and best practices for SOA start to emerge

• The first SOA-based corporate solutions go live

• SOA will attract more attention in the next few years

References• [1] Foster, I. et al. Open Grid Services Architecture V1. 2004.• [2] Booth, D., et al. Web Services Architecture. W3C, Working Draft

http://www.w3.org/TR/2003/WD-ws-arch-20030808/, 2003.• [3] Anantharangachar, R. Myths About Service-Oriented Architecture, Web Services

Journal, August 2005• [4] Carges, M. Taking SOA from "Pilot to Production" with Service Infrastructure

http://www.infoworld.com/event/soa/InfoWorld_SOA_Mark_Carges.ppt• [5] Curbera, F. et al., Web Services Platform Architecture: Soap, WSDL, WS-Policy,

WS-Addressing, WS-Bpel, WS-Reliable Messaging and More, Prentice Hall PTR, 2005

• [6] Kamdal, M. SOA – Taking a Structured approach. BEA Architects Summit, http://ftpna2.bea.com/pub/downloads/architectsummitpresentations/SOA_Taking_A_Structured_Approach.pdf

• [7] Roth, B. Service-Oriented Architecture Best Practices, http://java.sys-con.com/read/48032.htm