2. Technologies for Enterprise-wide SOA
Generic Technologies
Platform-supported Technologies
Standard-based Technologies
Vendor Specific Technologies
Tools from vendor that support generic technologies but offer additional
capabilities for improved productivity and quality
3. Generic Technologies for service Enablement
RESTful Web services
-Representative state transfer
-Based on HTTP
-It offer lower overhead in interactions between service providers and
service consumers
SOAP Web Services
-W3C defines web service as software system designed to support
interoperable machine to machine interaction over a network
4. Web service
It has two objectives
Enable interoperability between heterogeneous system.
Standard approach to define service interface independent of technology.
Web services Definition Language (WSDL) based on XML
Main Components of web services
Service Provider
Service registry
Service Consumer
5. Open standards supported by web services
XML for data interchange
HTTP,FTP and SMTP for transport
SOAP for Messaging
WSDL for interface description language
UDDI for registry
6. XML is text based extensible markup language without fixed tags. An
XML document is always structured with tags defining the items that it
holds and so XML parsers can be used to retrieve the data from it.
During a web service call, an XML message with application data is
wrapped in a SOAP Envelope,that is a header and trailer is added to
the application data that describes the message structures passed.
Wire-level security-while the former may be achieved by enabling
HTTPS at web server level
Message –level security involves security of data in SOAP
messages.WS-security provides a standard approach to encryption and
use of digital signatures headers in SOAP messages.
7.
8. WSDL(Web service Definition Language)
Functional
How the service is invoked(abstract interface,concrete implementation)
Non-functional
Why a client invokes the service and who the service provider(policy)
9. JAX-WS for java EE platform
JAX-WS stands for java API for XML web service and was formerly known
as JAX RPC.
Service consumer application creates a proxy object and then invokes
method on this proxy.
Neither the service provider application nor the service consumer
application is required to generate or parse SOAP messages.
Web services interoperability technology(WSIT) provides interoperability
between java web services and Microsoft window Communication
Foundation.
10. Features supported by WSIT
Bootstrapping communication
Securing communication
Optimizing communication
Enabling reliability
Enabling atomic transactions
11. XML web services for .NET platform
There are mainly three ways by which web services
Microsoft WCF
Basic .NET
Web service software Factory
12. Service Enablement of Relational Databases
Extensive adoption of web services has incentivized key database
technology providers to develop features that allow web services to be
exposed at database level.
Service Broker Feature of Microsoft SQL server
Web service for oracle Database server
Stored procedure web service feature for IBM DB2 UDB
13. Technologies for Service Integration
Issues related to while service consumers can directly invoke services based
on the WSDL providers
It become necessary for a service consumer to use the same protocol as
that of a service provider.
The message format used by the service consumer for service invocation
may be different from the format required by the service provider.
A larger number of service providers and consumers may result in
increased complexity due to several point to point connections
14. Contd..
Products that support the concept of ESB are available from
Application service providers
Middleware Vendors
ERP providers
Open source
Service integration with ESB
A proxy service is registered in AquaLogic for the Loan Service developed
with Apache Axis and developed on Tomcat server
15.
16. Business Case for SOA
A business case is developed considering the following
Stakeholders objectives
Benefits of SOA
Cost Savings
Return on Investment
17. Stakeholders objectives
A SoA initiative needs to fulfill the objectives of stakeholders
Sponsors
SOA initiatives are sponsored by CXOs,The strategic advantages that the
sponsors of SOA look for include
Alignment of business and It
Reduced time to market
Agility
Vendor independence
Competitive Edge through leverage of new Technologies
18. Business
Enterprise have business units that deliver products and services and IT
departments that provides hardware and software infrastructure to enable
business through implementation of their business process.
IT
With the availability of IT infrastructure that enables externalizing of
business process and the maturity of packed application platform.
19. Benefits of SOA
Business Agility
Shorter Development cycles
Reduced time to market
Lower total cost of ownership
Strategic Architecture
Alignment of IT and business
Interoperability
Effective Integration
Improved Efficiency
20. Cost Savings
The cost saving can be computed as
Development cost savings=[(N*R)/100]*(C*A)
N-number of services that are reusable
R(%)-Degree of reuse
C=Complexity of services(average no of functions or objects points per
service)
A=Average cost per function point or object point
21. Return on Investment(ROI)
Approval of a business case by decision makers in an enterprise.
ROI three dimensions as reuse,integration and agility.
ROI=(DCS-EXP)/EXP
DCS-Development Cost Savings(due to reuse & integration)
EXP-Expenditure towards hardware,software,network and
development support
22. Build a case for SOA
The primary drivers for SOA vision are IT cost savings, customer service
improvement and faster time to market.
Three areas of impact as result of soa
Customer service improvement
faster time to market
information visibility
Four main roadblocks for justifying SOA in organizations
Lack of confidence
Securing funding