Service orientation provides benefits for businesses by enabling them to move from brittle, hardwired application silos to shared, reusable business and infrastructure components. This eliminates application redundancy and complexity, enabling business agility, innovation and operational excellence. The document discusses service orientation at eBay, where over 300 services have been developed to organize the enterprise as reusable business functions and reduce costs of new features and applications. Challenges of service orientation include technical issues like latency and security as well as ensuring developer adoption and effective governance processes.

1. Service Orientation
Why is it good for your business
By
Sastry Malladi
eBay Inc

2. Overview
 Service Orientation Intro
 Different Service styles
 Challenges
 Case Study : eBay
 Recap
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3. Fun facts about eBay
 eBay manages …
 Over 97 million active users
 Over 2 Billion photos
 eBay users worldwide trade on average $2000 in
goods every second ($ 62 B in 2010)
 eBay averages 4 billion page views per day
 eBay has over 250 million items for sale in over
50,000 categories
 eBay site stores over 5 Petabytes of data
 eBay Analytics Infrastructure processes 80+ PB of
data per day
 eBay handles 40 billion API calls per month
In 40+ countries, in 20+ languages, 24x7x365
>100 Billion SQL executions/day!

4. Service Orientation
An architecture style to move from
brittle, hardwired, application silos
that inhibit change…
… to shared, reusable, business
and infrastructure components…
… which eliminates application
redundancy and complexity, and
enable Business Agility, Innovation
and Operational Excellence.
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5. Terminology
 Service
 Well defined piece of functionality, with a defined interface, with fully
encapsulated business logic and data, that is managed and exposed
consistently, and which is independent of any data formats and
message protocols
 Data Binding/Format
 The format in which the data is represented on the wire (e.g XML, NV,
JSON, BinaryXML, ..) –a.k.a Wire Format
 Message Protocol
 The protocol followed by the client and service when exchanging
messages (e.g, SOAP).
 Transport protocol
 Protocol used at the transport level (e.g HTTP, SMTP)
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6. Services - Not just technology
Technolo
Services Process
gy
Run-time stack
Integrated tooling
Domain modeling
Life-cycle mgmt
Infrastructure services Governance
Registry/Repository PDLC changes
Routing
People
Think interfaces
Promote Reuse
Biz and IT alignment
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Training & Docs

7. Some common Misconceptions dispelled
 SOA is a new technology
 It’s an architecture paradigm applied to existing or new technologies
 SOA implies Web Services and SOAP
 WS/SOAP is not an exclusive protocol. REST style with JSON, NV is more popular in
the current days
 SOA/Services is an end in itself
 SOA is a means to enable business agility
 Services are always developed from ground up
 Business always leverage existing functionality, but morph them into services and
develop some new services on the way
 At service development time, its consumers are known
 Service development may start with some use cases in mind, but they will evolve over
a period of time

8. Enabling possibilities
TOMMOROW
TODAY
FUTURE
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9. Services benefits
 Business Agility
 Faster time to market for new business offerings
 Quicker response to business change
 Easier integration with partners and third parties and adjacencies
 Innovation
 Enable internal and external Innovation
 Operational excellence
 Reduced cost for any new feature development
 Better developer productivity
 Reduced cost of failure

10. Typical steps for Service orienting
your business
 Do the domain modeling for your enterprise
 Decompose domains into components
 Intersection between domains should be zero
 Assign owners and architects to domains
 Choose on Central Vs decentralized governance
 Get Business and Technology alignment
 Pick a technology stack, including tools for Dev, QE and
Ops
 Train the developers
 Execute, track progress and course correct.

11. Overview
 Service Orientation : Benefits
 Different Service styles
 Challenges
 Case Study : eBay
 Recap
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12. Different Service Styles
• SOA
• Formal Contract, interface (WSDL or other)
• Transport / Protocol agnostic (bindings)
• Arbitrary set of operations
• REST
• Based on Roy Fielding’s dissertation
• Web/Resource oriented
• Suits well for web based interactions
• Piggy backs on HTTP verbs : GET, POST, PUT,
DELETE
• No formal contract

13. Overview
 Service Orientation : Benefits
 Different Service styles
 Challenges
 Case Study : eBay
 Recap
13

14. General Challenges
 Technical
 Additional latencies due to multi-hop communications
 Debugging/Tracing is harder
 Need for efficient Request/Session level caching
 Increased Security and monitoring challenges
 Multiple, often competing standards
 Operational
 Developer adoption and learning curve
 Governance processes
 Migration of existing Apps
 Updates to existing tools and processes.
 Deployment and rollout
 Measurement of progress and ROI
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15. Further challenges in large scale deployments
 Technical
 Co-existence of old and new technologies during transition phase
 Supporting internal and external clients that have different
protocols/data binding needs, for the same service deployment
 Integration testing
 High availability and Scalability – high volume and low latency
 Decomposition of existing apps and migration of legacy services
 Operational
 Version and dependency management
 Time to Market pressures
 Need for a strong yet simple governance process
 QoS and SLA management
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16. Overview
 Service Orientation : Benefits
 Different Service styles
 Challenges
 Case Study : eBay
 Recap
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17. Services @eBay
 It’s a journey !
 History
 One of the first to expose APIs /Services
 In early 2007, embarked on service orienting our entire
ecommerce platform, whether the functionality is internal or
external
 Support REST style as well as SOA style
 Have close to 300 services now and more on the way
 Learned a lot from feedback from our customers and
operational issues and evolved our technology and strategy
over time
 Early adopters of SOA governance automation
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18. Services @eBay – Contd.
 Technology stack
 Mix of highly optimized home grown framework
components as well as best of breed commercial and
open source components , integrated together – All
standards based (WSDL, Http, JAX-WS, JAX-RS ..)
 Goals
 Organize the enterprise as a set of reusable business
functions
 Reduce the cost of new features and applications
 Encourage and enable new business opportunities

19. Addressing the challenges
 Technical
 Policy driven Light weight and high performant Services platform
 Model-driven Service decomposition
 Support for REST and SOAP style from the get go
 Unified Testing framework and service virtualization
 Constantly evaluate and iterate over technology..
 Operational
 Simple and flexible governance processes and life cycle management, iterated over
time
 Strong operational management and monitoring tools
 Developer training and incentives for being a good citizen
 Formal process and tools to measure adoption and progress.
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20. Services platform overview
Dev/Arch Life cycle/dependency mgmt
Design/Dev
Develop
Services, consumers, Registry/
Eclipse
Repository
Dev tools
Assertions
Test tools svc
Registry
clients services
SOA/REST client SOA/REST Server
Runtime
Framework Framework
External routing
(ESB)
Authentication Authorization RL Monitoring Logging
Rest Mapping
Admin console Policy service
Monitoring console
Tier
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21. A word on ESB
• Decouple of service consumers from service
producers:
• Routing and transformation
• Support QoS
• Minimal latency overhead and high scalabilty
• Evaluated various products and selected
WSO2 ESB
• It rocks !
• It processes more than 1B messages per
day !
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22. Service Layers and Taxonomy
 Defining a finite set of service layers and their
relationships
 Goals
 Provide a mechanism to build and layer services that have different
characteristics
 Enable service lifecycle management for services with different scopes of
impact
 Clearly establish guidelines on what functionality can be implemented in
which layers
 Define allowed access patterns between layers
 Enable better dependency and rollout management
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23. Our specific taxonomy
Application Layer
Business
controlled
Intermediate/Core
d
le
tr ol
Common/Infrastructure con
OK
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24. What is Service governance
 A set of activities related to exercising control over design, development
and life-cycle of Service providers and Service consumers, for
consistency manageability and for promoting re-use
 Design time
 Interface and types design review and approval
 Enforcement of consistency guidelines for contract (interface, policies and behavior)
 Enforcement of dependency and layering guidelines
 Runtime
 Deployment policies
 Security/caching/monitoring/availability policies
 Reconciliation between what it is (runtime) and what it should be (design)
 Change management
 Dependency and impact analysis
 Versioning (both major and minor) of existing services
 Making sure existing subscribed clients don’t break.
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25. Governance process - Sample
Dev tools
Service Registry and Repository
Life cycle stages
Publish/discover
Proposed Approved Tested Deployed
Build
tools
Deployment Notify Notify Notify Notify
tools
Release
tools
External External External External
governance Governance Governance Governance
process process process process
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26. Governance – Our journey
 We initially had an elaborate governance process
 After feedback from developers, we iterated and
eliminated this and made it a self service process
 Validation and Reporting
 Data from this repository is exported to runtime
ESB registry and SIF.
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27. Tracking Adoption
Ref : Wikipedia
 After domain decomposition into services, need to set goals and closely track
Adoption – at least until you cross the “chasm”
 Formulas for tracking adoption index and ROI
 One yardstick – 3 uses of a service is break even, anything more is bonus

28.  eBay has been a strong supporter of Open Source model
and community
 Recently created http://eBayOpenSource.org
 Mission is to open source some of the best of breed technologies
that were developed originally within eBay Inc.
 For the benefit of the community
 Under a liberal open source license.
 These projects are generic technology projects and several years
of development effort has gone into them to mature them.
 Most parts of our services platform, code named Turmeric, is
open sourced on this site.
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29. Recap
 Moving to Services model certainly has its benefits, but brings along
bigger challenges
 Solving the technology part is relatively easy. Operational aspects are
more challenging and need to address them from the beginning
 Restful Services is where the industry is headed.
 Up front design and modeling of your contract/interface, including
granularity is very important
 Service layering, dependency and version management must be well
thought through
 Invest upfront on developer training, Testing tools, and some form of
governance
 eBay has been successfully able to apply this strategy and make
progress in our service orientation journey.
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30. Q&A