1. Architecture, Styles, and Service Oriented Architecture
Richard Osborne
September 22, 2006

2. Architecture Defined
the art of creating an actual, implied or apparent plan of any complex object or system
a subjective mapping from a human perspective to the elements or components of some kind of structure or system, which preserves the relationships among the elements/components

3. IT or Systems Architecture
Many definitions
the representation of an engineered system, and the process and discipline for effectively implementing the design(s) for such a system. Such a system may consist of information and/or hardware and/or software
The fundamental organization of a system, embodied in its components, their relationships to each other and the environment, and the principles governing its design and evolution. From ANSI/IEEE

4. IT or Systems Architecture
A representation of a system in which there is a mapping of functionality onto hardware and software components, a mapping of the software architecture onto the hardware architecture, and human interaction with these components. From the Carnegie Mellon University's Software Engineering Institute
An architecture description is a formal description of a system, organized in a way that supports reasoning about the structural properties of the system. It defines the [system] components or building blocks...and provides a plan from which products can be procured, and systems developed, that will work together to implement the overall system. It thus enables you to manage...investment in a way that meets [business] needs. From The Open Group Architecture Framework

5. IT or Systems Architecture
All have some common elements:
Structure
Components
Relationships
Purpose
Plan

6. Enterprise Architecture
Applying IT Architecture disciplines to an enterprise
Outside-in, strategy-driven, top-down viewpoint
Alignment – the “holy grail”
the practice of applying a comprehensive and rigorous method for describing a current and/or future structure and behavior for an organization's processes, information systems, personnel and organizational sub-units, so that they align with the organization's core goals and strategic direction

7. Enterprise Architecture
FEA – Federal Enterprise Architecture
Core Principles:
Business-driven
Proactive & collaborative across the Federal government
Architecture improves the effectiveness and efficiency of government information resources
No IT investment without a business-approved architecture

8. Enterprise Architecture
Alignment of business strategy & IT investments
Architecture is the translation of business strategy into technical strategy
Use of a framework to:
Document current state
Define the future state desired capabilities
Create a roadmap to get there
There are many reference frameworks
Zachman
FedArch
E2A
TOGAF

9. Enterprise Architecture
All have some combination of the following concepts:
Business
Information
Technology
Application
Contextual
Conceptual
Logical
Physical

10. Reference Architecture
Reference architecture - a style or method
a coherent design principle used in a specific domain
describes the kinds of system components, their responsibilities, dependencies, possible interactions, and constraints.
basis for designing the system architecture for a particular system.
the architect can select from a set of well-known elements (standard parts) and use them in ways appropriate to the desired system architecture

11. Reference Architecture
Pre-defined architectural pattern
Designed and proven for use in particular business and technical contexts
Often harvested from previous projects
Best practices
Abstract solutions from many previous attempts
Example - Open System Interconnection model defines a networking framework for implementing protocols in seven layers

12. Service Oriented Architecture
A collection of services that communicate with each other
A service is a function that is well-defined, self-contained and does not depend on the context or state of other services
From simple data passing to two or more services coordinating (orchestrating) some activity (business process)
Not a new concept

13. Service Oriented Architecture
Service Oriented Business Applications (Loosely Coupled, Business Services as Assets)
Application Silos with Components
(Tightly Coupled and Limited Reuse)
Service Oriented Architecture
Monolithic Architecture
(Tightly Coupled, Application Silos)
Component Based Architecture
Monolithic Architecture
Time

14. Service Oriented Architecture
Next stage of integration
Services
(SOA)
What’s
Next?
Business Process Management
EAI
Message
Processing
Remote
Object
Invocation
Sub-routines
&
Remote
Procedure
Calls
Monolithic
Architectures
Pre 50’s
- 60’s
70’s -
mid 80’s
80’s -
Mid 90’s
Mid 90’s to
Early 00’s
Late 90’s
Today
Future

15. Why is Integration Important?
Investments made in “legacy” systems
Trillions of $ over the past 40 to 50 years
Remember Y2K?
Mainframe
Distributed Client-Server
Web
Application Packages such as ERP
Cost and Time to develop & deploy new business functionality
Rates from $30/hour (off-shore) to $300+/hour
A small 5 person year project (10,000 hours) can easily cost in excess of $2M and take a year to deliver

16. Why is Integration Important?
Why develop a new system/business function when you already have it?
Is it “locked up” in a different technology?
The cost to maintain two of the same is not 2X but 3X .. Or more
SOA is a way to re-use the assets that most organizations already own
Break down the existing systems into components that can be combined in new ways
A flexible, standards-based integration method is needed

17. Why is Integration Important?
EAI
SOI
Custom Point-to-Point Integration uses technology aware bridges between application components; very brittle for changes.
EAI uses broker-specific adaptors which provide pre-built connectivity to a wide variety of applications & platforms; less brittle for changes than P2P.
SOI integrates applications & platforms using service interactions & an ESB; is the least brittle for changes.

18. How do we achieve integration?
The Silo – monolithic architecture
User Interface
Business Logic
Data Access
Data

19. How do we achieve integration?
Separation of Concerns
User Interface
Integration Layer
Business Logic
Integration Layer
Data Access
Integration Layer
Data

20. SOA Definitions - Viewpoints
a set of services that a business wants to expose to their customers and partners, or other portions of the organization
an architectural style which requires a service provider, requestor and a service description
a set of architectural principles, patterns and criteria which address characteristics such as modularity, encapsulation, loose coupling, separation of concerns, reuse, compose-ability and single implementation
a programming model complete with standards, tools and technologies such as Web Services

21. SOA Reference Architecture
Data Architecture and Business Intelligence
Monitoring Infrastructure Service
QoS, Security, Management, and
Integration (Enterprise Service Bus Approach)
consumers
business processes
process choreography
services
atomic and composite
service components
operational systems
Service Consumer
Service Provider
AJAX
Portlets
WSRP
B2B
Other OO
Application
Custom
Packaged
Governance

22. SOA's Standards Foundation
BPEL (Business Process Execution Language): a standard for assembling sets of discrete services into an end-to-end business process
J2EE 1.4: the current version of Java 2 Platform, Enterprise Edition, with APIs for deploying and managing Web services
JSR 168: standard for portal and portlet interoperability
JSR 181: an API for Web services metadata annotation
SOAP (Simple Object Access Protocol): a W3C-approved standard for exchanging information among applications
UDDI (Universal Description, Discovery, and Integration): an OASIS-approved standard specification for defining Web service registries
WS-I (Web Services Interoperability): an open industry organization promoting Web services interoperability across platforms, operating systems, and languages
WS-Reliability (Web Services Reliability): a SOAP-based protocol for exchanging SOAP messages, with delivery and message-ordering guarantees
WS-Security (Web Services Security): a SOAP-based protocol that addresses data integrity, confidentiality, and authentication in Web services
WSDL (Web Service Description Language): a W3C-approved standard for using XML to define Web services
WSIF (Web Services Invocation Framework): an open source standard for specifying, in WSDL, EJB implementations for the Web server
WSRP (Web Services for Remote Portlets): an OASIS standard for integrating remote Web services into portals
XML (Extensible Markup Language): a data markup language for Web services

23. Conclusion Architecture plays a role in Enterprise IT
EA is often used to align what IT does and plans to do with the business strategy
There are frameworks that help how to think about the problem
There are reference architectures to help how to create an approach
There are architectural patterns to help in thinking how to build and deploy solutions
There are architectural styles that can be applied in solution design