Download PowerPoint Presentation

ConfidentialConfidential

Service Oriented Architecture Service Oriented Architecture

What it is and why you need it.

April 25, 2007 SOA: What it is and why you need it. Slide 2/19Final

AgendaAgenda

Why SOA What is SOA? Government of Canada SOA Oracle SOA Suite Some of the Challenges Conclusion


Why SOA?Why SOA?

“The business simply wants composable, reusable, interoperable, unbreakable components they can leverage in flexible ways to meet the changing needs of the business.”

ZapThink Dec 11, 2006


Why SOA?Why SOA?

“Departments have a huge investment in their application environment, horizontal government programs and mandates are becoming increasingly common, new development is so expensive – there must be a better, faster, cheaper way to do things.”

IT/NET, April 2007


What is SOA? What is SOA? Some definitionsSome definitions

Service “useful labour that does not produce a specific

commodity” “a facility supplying some public demand”

Source: Merriam-Webster Online

Architecture The description, through words and/or pictures of the

elements of a system and their interactions with each other and with other systems

Service Oriented Architecture The description of the system elements that enable the

supply of something useful which has a public demand


What is SOA?What is SOA?ExampleExample


What is SOA? What is SOA? Elements of SOAElements of SOA

Defined Service Types Tells developers how to approach a task Guides analysts in “what’s possible” Shows how to do the same thing on multiple platforms

Process Driven Software A transition away from the traditional task- centric

Applications Designed to mirror the way people work Consumes services in support of processes Permits transfer of data/functionality across organizational

boundaries Exposure of existing software components as services Build as you go


What is SOA? What is SOA? Defined Service TypesDefined Service Types

Service

Contract

Implementation

Business Logic Data

Interface 1Operation aOperation b

.

.

.

Interface 2Operation aOperation b

.

.

.

Services Types support: Estimating Consistency of

implementation Communication Reusable Functionality


SOA Metamodel

What is SOA?What is SOA?Process Driven SoftwareProcess Driven Software

Service Model

Business ModelPlatform-Dependant Models

Platform-Dependant Models



Business Process Definition

Requirements Implementation

Service Oriented Process


What is SOA? What is SOA? SummarySummary

Service Oriented Processes and system working together to provide

something of value Architecture

The definition and communication of: how it is done and how to do it

The ultimate value provided by Service Orientation is that it permits existing software assets to be used longer, in more ways that mirror the way your organization does things


The GC SOAThe GC SOA Treasury Board-CIOB is actively engaged in developing and

distributing an SOA for the Government of Canada It provides guidance and a foundational reference framework

for a common approach to application interoperability Identifies 3 layers (tiers)

Technology Component Layer “Understanding, classifying and purposing all GC IT

Architectures” Service Exchange Architecture

“Standardizing the run-time aspects of the GC IT Enterprise” Describes Services of Services (“Automated Business

Services”) and “Infrastructure Services” Business Application Architecture

“Standardizing the design-time aspects of the GC IT Enterprise” Layered application architecture that allows Business Owners to

leverage pre-built services


The GC SOAThe GC SOA

Source:Government of Canada Service Oriented Architecture Series – Primer (http://www.tbs-sct.gc.ca/cio-dpi/webapps/architecture/p-gi/p-gitb_e.asp

Business Application Architecture

Enterprise Services Interface (ESI)

Interaction Layer

Persistence Layer

Object Layer

Process Layer

Application Services Bus (ASB)

Presentation Layer


SOA ToolsSOA Tools


Some ChallengesSome Challenges Resistance to change

Current monopolies on app development are reduced Perception that building something once means current

teams could start to run out of things to do – teams must find more specialized things

There are limits to what you can do The building block can only take you so far – at some point

you may need a Mechano set to build more complex things Components are interoperable with each other but not with

other kinds of components Creeping Complexity

An individual SOA component may be simple Overtime, the enterprise level SOA will become something

substantial - requires thought, planning and skill, i.e. architecture and training


Some ChallengesSome Challenges Finding the right ‘granularity’

Differences in individual mandates and operations means differences in granularity are needed

Some Services will do very simple things (e.g. Return a single value)

Some will do very complex things (e.g. Update Local database, initiate an approval process, send to partner, then notify originator)

Complex services appear more valuable to the business but flexibility is reduced as complexity increases

There’s no “best” SOA Just like with Lego, you need a certain degree of variety and

personal choice Organizations will build a mix of Services at different levels of

granularity GoC SOA defines 2 levels: Business Services and Infrastructure

Services


Conclusion:Conclusion:Architecture PrinciplesArchitecture Principles

Renovate, don’t rebuild You are not re-engineering, you are extending your existing

application environment through planning, design and management Always keep the critical objectives in mind

Alignment of systems and business Reuse of existing software Quick turn-around

You MUST decouple the System Architecture from the Software Architecture

Don’t try to map a traditional Client server tiers to SOA tiers SOA MUST extend to the ERP

The ERP is probably the single most significant software investment made by the department

SOA values comes from re-use and renovation, what’s the point if you aren’t re-using and renovating your biggest piece of technology.


Conclusion:Conclusion:Going ForwardGoing Forward

Focus on your needs, engage key participants Determine Governance, basic standards Make sure you have a very good understanding

of your current assets Set priorities – look for services that are based on

new ways to use current technology Start defining Services and your SOA metamodel

Start with types based on GoC SOA as starting point

Extend them for what you need to do


Conclusion:Conclusion:Service Oriented ArchitectureService Oriented Architecture

What it is An SOA is the description of the system elements that

enable the supply of something useful which has a public demand

An approach to quickly leverage existing software resources for new and more complex purposes

Why you need it Applications need to work more closely with other

agencies Need to integrate program systems more tightly with

Corporate Systems Need to improve the way applications are built

Increase flexibility, reduce cost, reduce time to deliver


More informationMore information IT/NET - [email protected] Treasury Board - CIOB ZapThink.com Enterprise SOA – Service Oriented

Architecture Best Practices; Dirk Krafzig, Karl Banke and Dirk Slama;

Prentice Hall December, 2005 Software Engineering Institute:

http://www.sei.cmu.edu/architecture/definitions.html

Download PowerPoint Presentation

Documents

Transcript of Download PowerPoint Presentation