This document summarizes key concepts related to web services technologies including service-oriented architecture (SOA), XML, SOAP, WSDL, and UDDI. It discusses how these standards enable application integration and interoperability. The rise of web services allows for a more flexible and agile approach to developing applications and integrating systems. Major benefits include loose coupling, reusability, and simplifying enterprise application integration. However, web services also face challenges related to performance and managing expectations.

1. Web Services Foundation Technologies
And How They Impact Enterprise Applications,
Business and the Web
Tan Miaoqing
Pankaj Saharan
Helsinki University of Technology

2. Agenda
• Web Services in General
• Service-oriented Architecture (SOA)
• Web Services Fundamental
– XML, SOAP, WSDL, UDDI
• Application Integration
• How Web Services impact the Web
• Problems and Challenges
2006-12-12
2

3. What is a Web Service?
The “Quick and Dirty” Definition:
A website without a Graphical User
Interface (GUI)..

4. No GUI???
Consider www.google.com
• WWW-based Search Engine
• Simple input
• Rich result set (hyperlinks, images, etc.)
What if you could design your own User
Interface but still use the google search
engine?

5. The Underlying Idea
• Provide useful functions via WWW
• Allow Developers to create Apps
• Developers responsible for GUI

6. Key concept: Service

7. Service-oriented Architecture (1/2)
Composable
Interoperable
SOA
Re-Usable
Loosely
Coupled
• A software architecture
– Uses loosely coupled software services to support the
requirements of business processes
– Different applications can exchange data and participate in
business processes, regardless of underlying implementation
details

8. Service-oriented Architecture (2/2)
• SOA focuses on the description of
business problem
– Previous approaches focus more on
specific execution environment technology
• Independent Services
– Separating service interface from the
execution technology, allowing IT
departments to choose implementation
• Business agility
– New applications can be developed by
composing existing services

9. Web Services
“The Web can grow significantly in power and scope if it is
extended to support communication between applications,
from one program to another”
-From the W3C XML Protocol Working Group Charter
GOAL: “enabling systematic application-to-application
interaction on the Web”
“Web services” is an effort to build a distributed
computing platform for the Web

10. Basic Web Services
Points to
description
UDDI
Registry
WSDL
Finds
Service
Web Service
Web Service
Client
Client
(J2EE, .NET,
(J2EE, .NET,
PL/SQL …)
PL/SQL …)
Points to
service
Describes
Service
SOAP
Invokes with
XML Messages
Web Service
Web Service
(J2EE, PL/SQL,
(J2EE, PL/SQL,
.NET,C/C++,
.NET,C/C++,
Legacy …)
Legacy …)

11. SOAP Is…
•
•
•
•
•
•
A “wrapper” protocol
Written in XML
Independent of the wrapped data
Independent of the transport protocol
Efficient (according to the W3C)
A uni-directional message exchange
paradigm

12. Message Anatomy
SOAP Envelope
SOAP Header
Header Block
...
Header Block
SOAP Body
Body Block
...
Body Block

13. Message Representation
<?xml version="1.0" ?>
<env:Envelope xmlns:env="http://www.w3.org/soap-envelope">
<env:Header>
<data:headerBlock
xmlns:data="http://example.com/header"
env:actor="http://example.com/actor"
env:mustUnderstand="true">
...
</data:headerBlock>
...
</env:Header>
<env:Body>
<data:bodyBlock xmlns:data="http://example.com/header">
...
</data:bodyBlock>
...
</env:Body>
</env:Envelope>
2002.2.4
13

14. WSDL
• An XML based grammar for describing the
capabilities of Web Services
• Extensible
• Jointly developed by Microsoft and IBM
• Similar in concept to IDL, but it’s not IDL
-IDL is platform dependent
-WSDL is platform independent

15. Using WSDL
As extended IDL: WSDL allows tools to generate
compatible client and server stubs
Allows industries to define standardized service
interfaces
Allows advertisement of service descriptions,
enables dynamic discovery and binding of
compatible services
-Used in conjunction with UDDI registry
Provides a normalized description of
heterogeneous applications

16. UDDI
• Universal Description, Discovery and Integration
• A project to speed interoperability and adoption of
web services
-Standards-based specifications for service
description and discovery
-Shared operation of a business registry on the web
• Partnership among industry and business leaders
• But still optional and not core Web Services
Technology

17. Fact…
Meaning?
How Web Services Impact enterprise applications,
business, and the Web

18. Application Integration (1/2)
• Enterprise Dislocation
Big Corporations
International Biz
Worldwide Market
Globalization
– Each department makes its
own decisions
– Processes of the business are
incompatible
• Interfaces are devised
between different business
tasks one by one
– Using different models and
communications protocols
• Hard to change the business
to respond quick shifts in the
market

19. Application Integration (2/2)
• Two types of Integration
– Internal: Enterprise Integration
– External: B2B Integration
• If all applications use a common
programming interface and
interoperability protocol
– Job of IT will be much simpler
• Integration Products

20. Web services and Integration (1/3)
Source from [1]

21. Web services and Integration (2/3)
• How XML helps simplify the integration
– Independently define data type and structure
– Provides a clear separation between the
definition of a service and its execution
• Separates technical issues from business issues
– Divides responsibility within IT departments
• Create services: dealing with underlying technology
on which service is being deployed and ensuring
services descriptions are right
• Consume services: assembling business process
flows, ensuring them accurately reflect business
requirements

22. Web services and Integration (3/3)
Focus on shared data and
reusable services
• Services (create)
– Business Logic
• Service Bus
– Integrate Services
– Communicate with App
• SOAP
– Interaction between
services and
applications
• Business Process Engine
– Drive an automatic
flow across multiple
services (consume)
• Service Repository
– Store and retrieve
services descriptions

23. Benefit
• Making the business more reconfigurable
– Devising common languages and protocols
between business processes
• Loose Coupling
– Reusable, Interoperable components
– Replace large, tightly-coupled, monolithic
systems and packaged software
– Simpler systems, lower-cost of maintenance, ease
of modification and integration with other systems
• Greater agility, inter-operability with other companies

24. Amazon’s WebOS Strategy (1/3)
• How Web Services impact the Web?
• Productizing their own infrastructure
– 10 years experiences in large-scale
distributed computing
• Make web-scale computing easier for
developers
– Hides complexity behind simple APIs and
offers services for a reasonable cost

25. Amazon’s WebOS Strategy (2/3)
• eCommerce
– Exposes Amazon's product data and e-commerce
functionality
– Retrieve detailed item information, including prices, images,
customer reviews, and more

26. Amazon’s WebOS Strategy (3/3)
• S3 (Storage)
– A huge hashtable, storing objects up to 5GB
– Minimal API for write, read and delete
– Service works over multiple protocols like HTTP
and BitTorrent

27. Meaning
• A new computing paradigm, where web
services give rise to a new web-based
operating system
• Key elements of WebOS
– Infinitely scalable storage, dynamic
indexing service, grid computing, etc
• A new way to think about application
development
• Lightweight companies will benefit
– Business agility, lower development costs

28. Open Thoughts
Problems, Future and Conclusion

29. SOAP (In)Efficiency
HTTP Request
HTTP Body
XML Syntax
SOAP Envelope
SOAP Body
SOAP Body Block
Textual Integer
Sender
0x0b66
Receiver

30. Future..

31. Gartner’s ‘Hype’ Curve
Key: Time to “plateau”
Visibility
Biometrics
Less than two years
Two to five years
Five to 10 years
Beyond 10 years
Grid Computing
Natural-language
search
Web Services
Identity services
Personal digital
assistant phones
Nanocomputing
Text-tospeech
E-tags
Personal
fuel cells
Technology
trigger
Peak of
inflated
expectations
Virtual
private
networks
Speech recognition in
call centers
Voice over IP
Bluetooth
Public key infrastructure
Peer-to-peer
computing
WAP/
Wireless
Web
Wireless
LANs/802.11
Location
sensing
Speech recognition on desktops
Trough of
disillusionment
Slope of
enlightenment
Plateau of
productivity
Maturity
Source: Gartner Group

32. A recent Kubernan survey
• Almost 90 percent of enterprises will employ
Web services within the next year

33. Gartner’s ‘Hype’ Curve
Visibility
Key: Time to “plateau”
Less than two years
Two to five years
Five to 10 years
Beyond 10 years
Web Services
Technology
trigger
Peak of
inflated
expectations
Trough of
disillusionment
Slope of
enlightenment
Plateau of
productivity
Maturity
Source: Gartner Group

34. Conclusions
• The Web services framework is being defined, standardized and
supported by the industry at a record pace.
• Broad industry acceptance and standard compliance will make it
ubiquitous.
• Will bring an unprecedented level of interoperability to Web
applications.
– app-to-app conversation
• Will provide “Develop once ,Use often” opportunity.
• The benefits of Web services, however, are not limited to the
Web!
– Loose coupling, re-usability, business agility
• Not Silver Bullet, but will be widely adopted
– For Enterprise Application Integration, etc

35. For more information
1. Understanding SOA with Web
Services : Newcomer and Lomow
2. SOAP : http://www.w3c.org/TR/soap
3. WSDL: http://www.w3c.org/TR/wsdl
4. UDDI : http://www.uddi.org

36. Thank You!!
• Journey to the West
– A famous Chinese legend about the Buddhist monk Xuánzàng's
pilgrimage to India with his three protectors during the Tang
Dynasty in order to obtain Buddhist religious texts