Overview 1 Agenda Evolution of network computing What is Web - - PowerPoint PPT Presentation
Web Services Overview 1 Agenda Evolution of network computing What is Web Services? Why Web Services? Where is Web Services? Web Services Architecture Web Services Standards Java APIs for Web Services J2EE as
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Things - 1014 Computers 108 Embedded Computers 1011
Desktops
Transfers Transfers Transactions Transactions Content Content Telemetry Telemetry Control Control
Clients Functions Organization Protocols
Waves of Network Computing
IP v6 IP v4
IP Layer
Switches Switches Packages Packages Thermostats Thermostats Clothes Clothes Phones Phones TVs TVs Cars Cars Games Games
Things - 1014 Computers 108 Embedded Computers 1011
Desktops
Client/Server Web Applications Web Applications Web Web Services Services
Fractal Fractal Polyarchical Polyarchical
N-tier
FT P Telnet HTTP
X
RPC/XDR SMTP
Clients Functions Organization Protocols
SOAP SOAP RMI/IIOP RMI/IIOP
Jini Jini Identity Identity UDDI UDDI
LDAP LDAP
JXTA JXTA
Waves of Network Computing
IP v6 IP v4
IP Layer
Phone Phone s s TVs TVs Cars Cars Games Games Switches Switches Packages Packages Thermostats Thermostats Clothes Clothes
Transfers Transfers Transactions Transactions Content Content Telemetry Telemetry Control Control
Software-as-a-Service Shrink Wrap
Locater Locater Payment Payment Authentication Authentication New New Service Service User’s User’s Device Device X10 X106
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Calendar Calendar Developer Developer X10 X106
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X1 X1
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Catch Catch Phrase Phrase The Network The Network Is the Is the Computer Computer Objects Objects Legacy to Legacy to the Web the Web The Computer The Computer Is the Is the Network Network Network of Network of Embedded Embedded Things Things Network Network
Scale Scale When/Peak When/Peak Leaf Leaf Protocol(s) Protocol(s) Directory(s) Directory(s) Session Session 100s 100s 1,000s 1,000s 1,000,000s 1,000,000s 10,000,000s 10,000,000s 100,000,000s
100,000,000s
100,000,000 100,000,000 s s 1984/1987 1984/1987 1990/1993 1990/1993 1996/1999 1996/1999 2001/2003 2001/2003 1998/2004 1998/2004 2004/2007 2004/2007 X X X X +HTTP +HTTP (+JVM) (+JVM) +XML +XML Portal Portal +RM +RM Unknown Unknown NS, NS+ NS, NS+ +CDS +CDS
+LDAP(*) +LDAP(*)
+UDDI +UDDI +Jini +Jini +? +? RPC, XDR RPC, XDR +CORBA +CORBA +CORBA, +CORBA, RM RM +SOAP, +SOAP, XML XML +RM/Jini +RM/Jini +? +? Schematic Schematic
Client- Server 3-Tier Web Application Web Services Hybrid P2P Fractal
TM 2
Business Systems Business Systems DB Server DB Server App Server App Server Web Server Web Server Browser Browser Client Client
Web Application
J2EE J2EE J2SE/ J2SE/ J2ME J2ME
Bus. Bus. Sys. Sys. DB DB App App Web Web Browser Browser Context and Identity Context and Identity (LDAP, Policy, Liberty) (LDAP, Policy, Liberty) J2EE J2EE J2SE/ J2SE/ J2ME J2ME
XML XML (UDDI, (UDDI, SOAP) SOAP)
Web Service
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capable of being defined, described and discovered by XML artifacts and
software applications
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Client- Server(C/S) silos Web-based computing Web Services/Peer-to- Peer
Servers Clients Clients Servers Internet PDA Cell Phone Server Laptop Kiosk Workstation
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programming languages
particular transport
(space/time)
independent
transports
processing
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interaction
components
interaction
integration of components (in the future)
aggregation (in the future)
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The Service Grid
Service discovery Service delivery Service Registry Service invocation Service registration
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Macro Service Micro Service Micro Service Micro Service Business Process Management
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Stock Service Portal
Input: Symbol Output: Price, News, Trade
News feed 1
Input: Symbol Output: News links
Brokerage 1
Input: Symbol, Price, Qty
User Nasdaq
Input: Symbol Output: Price
News feed n
Input: Symbol Output: News links
Brokerage n
Input: Symbol, Price, Qty
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standard way
interoperable way
ubiquitous plumbing
integration
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networks using ubiquitous web-based standards
installation and tight integration of software
even for highly complex transactions
exposed and accessible on the web
anytime
amount of heterogeneous applications
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Supplier Logistics Distributor
Manufacturing Facility
Internet
XML XML XML XML
“Growing need for a standard lightweight infrastructure for data exchange in e-business applications.”
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Web Services
System Service App Service System Service App Service System Service App Service
A Computer System Software Application
Monolithic Software The Network
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Net worth News Stock ticker “Portfolio” can be an application, a portal channel, or a web service itself
A web service is accessed programmatically by applications or other web services
Web Services Portfolio
Bank Balance
Stock Position Insurance Cash Value Biz News World News
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Grammar
Bank balance
Publishing Media “Word processing” can be an application, a capability, or a web service itself
A web service is accessed programmatically by applications or other web services
Web Services Word Processing
Spell Check
Dictionary Thesaurus c:\...
http://...
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– Computing power doubles every 18 months
– Network bandwidth capacity doubles every 12
months
– Value of network increases exponentially as
number of participants increases
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Web Services Custom Integration
Metcalfe’s Law: The value of the network is proportional to the square of the number of
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Concept Basic Web Services Interface Description CORBA IDL, Java interface WSDL RPC support ORBs, Idl2java compilers, rmic SOAP, compilers for WSDL Service Registry CORBA naming service, JNDI UDDI Messaging support CORBA Event/Notification service, JMS ? Transaction support CORBA Transaction service, JTS ? Secuity support CORBA Security service, Java security ? Distributed Computing ala CORBA / Java
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UDDI: We need more high-level semantics
paradigm: Document-driven model would be more popular communication model
Other transports such as SMTP can be also used
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– SOAP, WSDL, UDDI are not enough
– Quality of Service, management – Security, transaction, state and user context – Work flow, Identity management, – Provisioning, Accounting
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– Concerted deployment internally within an
– SOAP over HTTP/S
– Selective and non-aggregate deployment with
trusted outside business partners
– Private registry deployment
– Wider, more dynamic and aggregate deployment
with outside business partners
– Public registry deployment
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HTTP/S
enable internal integration
transactions with trading partners, suppliers,
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source projects support ebXML
NOW!
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B2B Collaboration
Simple interaction Consumer oriented Short-living process No business
collaboration
No partner profile Not secure, not
reliable
Does not support
non-repudiation
No repository
support
No legal binding Complex interaction Business oriented Long-running process Supports business
collaboration
Supports partner
profile
Secure and reliable
and non-repudiation
Supports non-
repudiation
Registry and
Simple Web Services
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B2B Collaboration
Within a
business
Centralized
control
Implicit contract Small number of
business processes and participants
Between
business
Distributed
control
Explicit contract Potentially large
number of business processes and participants EAI
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– Composable and composite services – Data encapsulated within component – Data ownership follows component ownership
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Registry
PUBLISH
Service BIND
Service Location FIND
Web Service Service Client
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– IIOP for CORBA – JRMP for RMI
– “text” based protocol vs. “binary” protocol
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– So it will not replace objects and
components, i.e. EJB, JavaBeans
– So it will not replace Java
– So it will not replace other distributed
computing technologies such as RMI
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SOAP Envelope SOAP Header SOAP Message Primary MIME part (text/xml) Attachment Attachment SOAP Body Header Entry Header Entry Body Entry Body Entry Attachment
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– Optional – Could contain context knowledge
– RPC methods and parameters – Contains application data
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– Built-in types from XML Schema, Part 2 (simple types, enumerations, arrays of bytes)
– Structs, arrays, complex types
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– A set of communication endpoints (ports)
– Abstract definitions of operations and messages – Concrete binding to networking protocol (and corresponding endpoint address) and message format
– Enhance reusability (as we will see in UDDI reference to WSDL document)
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– Machines can read WSDL – Machines can invoke a service defined in WSDL
– 3rd party can verify if communication conforms to WSDL
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UDDI defines a way to publish and find information about Web services.
UDDI Registry
PUBLISH
Service BIND
Service Location FIND
Web Service Service Client
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– address, contact, and known identifiers
– industrial categorizations
– technical information about services
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B2B Applications B2C Applications Web S ervices Wireless Applications
Application Server
Enterprise Information S ystems
Existing Applications
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– No architectural change is needed – Existing J2EE components can be easily
exposed as Web services
– Portability, Scalability, Reliability – No single-vendor lock-in
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– Over different vendor platform – Over different operational environment
– High-level Java APIs – Use existing deployment model
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– Umbrella framework for Web services – JSR 109, JAX-RPC, JAXR, EJB 2.1, Servlet
2.4,
– Defines client programming model – Defines Servlet-based Web services endpoint
model
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– Defines Stateless Session Bean-based Web
services endpoint model
– Will be aligned with JAX-RPC
– Defines standard Web services packaging and
deployment model
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– Container provides runtime environment – Contract for runtime environment are specified in
JAX-RPC, EJB 2.1, JSR 109
– WSDL specifies a contract between service
provider and client
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– Web services components get executed within a
container
– Components are portable (under J2EE 1.4)
– Web-tier (Servlet-based endpoint) – EJB-tier (Stateless session bean-based endpoint)
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Source: Web Services for J2EE (JSR 109), V1.0
Web services components
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program to program communication
Services are now available!
services
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