2. Agenda
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Software and Services
A Short History of Semantic Web Services
Linked Data Effect
Rise of REST
Linked Data and Services
Example Applications
Current and Future W3C work
Summary
4. Software
• Slow to produce!
– 10 lines of code per day
• Code is ubiquitous
– Car has 2 million lines of code
(8,000 Person Years)
– Windows XP 45 million lines of code
(180,000 Person Years)
• Reusability is important
5. Service (economic)
• Intangible commodity
– Consulting, childcare, educational
• Tertiary sector of the economy
– Provision of value-adding services
– Complementing
• secondary sector manufacturing and
• primary sector: agriculture, fishing, mining …
– 63% of Global GDP $44 trillion
7. Web Service Usage Process
• Deployment
– create and publish Web service description
• Discovery
– determine usable services for a task
• Composition
– combine services to achieve a goal
• Selection
– choose most appropriate service
• Mediation
– solve mismatches (data, protocol, process) that hamper
interoperation
• Execution
– invoke Web services following programmatic conventions
8. Web Service Execution Support
• Monitoring
– control the execution process
• Compensation
– provide transactional support and undo
or mitigate unwanted effects
• Replacement
– facilitate the substitution of services by
equivalent ones
• Auditing
– verify that service execution occurred in
the expected way
14. Class Hierarchies of Services
name
provider
avgResponseTime?
…
ServiceProfile
ProductProviding
Service
InfoService
informationProduct+
physicalProduct+
manufacturer+
deliveryRegion*
deliveryProvider*
deliveryType
PhysicalProduct
Service
FeeBased
feeBasis+
paymentMethod+
ActionService
physicalProduct+
Manufacturing
Repair
physicalProduct+
Tie in with UNSPSC, etc.
Transportation
DL Basis for matchmaking
Multiple profiles; multiple hierarchies
transportationMode+
geographicRegion+
15. WSMO Top-level Elements
(http://www.wsmo.org)
Objectives that a client may have
when consulting a Web Service
Provide the formally
specified terminology
of the information used
by all other components
Semantic description of
Web
Services:
- Capability (functional)
- Interfaces (usage)
Connectors between components with
mediation facilities for handling
heterogeneities
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16. WSMO – the Web service element
- complete item description
- quality aspects
- Web Service Management
- Advertising of Web Service
- Support for WS Discovery
Non-functional Properties
Capability
DC + QoS + Version + financial
functional description
client-service
interaction interface
for consuming WS
- external visible
behavior
- communication
structure
- ‘grounding’
Web Service
Implementation
(not of interest in
Web Service
Description)
Choreography --- Service Interfaces ---
WS
WS
WS
Orchestration
realization of
functionality by
aggregation
- functional
decomposition
- WS composition
18. Orchestration Definition
Flight Request
VTA
provides
if hotel = Ø
flight.arrivaltime = hotel.arrivaltime
Capability
Chor.
Interf.
VTA WS
‘Trip Booking’
if flight = Ø
Hotel Request
flight information
Book Flight
Book Hotel
hotel information
process (control + data flow) of goals
19. Runtime Orchestration
Capability
flight request
Flight Request
VTA
provides
avaiable flights
Capability
Hotel Request
VTA WS
‘Trip Booking’
Flight WS
Orch.
..
if hotel = Ø
book request
Chor.
Interf.
Interface (Chor.)
1) get request
2) provide offer
3) receive selection
4) send confirmation
hotel request
avaiable hotels
if flight = Ø
Book Flight
booking confirmation
Interface (Chor.)
1) get request
2) provide offer
3) receive selection
4) send confirmation
book request
booking confirmation
Book Hotel
process (control + data flow) between “states”
+ communication behavior of orchestrating Web Service
Capability
Hotel WS
Orch.
..
27. RESTful Service
• Lightweight compared to SOAP/WSDL
• Use HTTP methods explicitly
(GET, POST, PUT, DELETE)
• Stateless
• Expose directory structure-like URIs
• Data transfer using XML, JavaScript Object Notation
(JSON), or both.
41. MicroWSMO
• Built on top of hRESTS which introduces the
service model structure on Web pages
– service (+ label)
– operations (+ address, method)
– input, output
• MicroWSMO extends hRESTS
–model, lifting, lowering
• Applies WSMO-Lite semantics
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56. Behind the Scenes
Public Data and Services
Service Broker
publishing
Real estate
discovery
Train stations
Bus stops
Schools
Invocation
Engine
invocation
62. This group is based on the idea of combining two Web-related concepts
to help solve some of the long-standing challenges involved in building
and combining software:
1. RDF, the Resource Description Framework…. RDF is the basis
for Linked Data and the Semantic Web.
2. With RESTful APIs and RESTful Web Services, ….
The Linked Data Platform is envisioned as an enterprise-ready
collection of standard techniques and services based on using RESTful
APIs and the W3C Semantic Web stack
63. Summary
• Web services successful history in corporate settings
– Supporting reuse of software components
• Semantic Web services
– Lots of research
– Takeup limited
• New trends
– RESTful services
– Linked Data portals/applications
• Manage applications which make
use of these trends
• Fit to the goals, needs and
contexts of users
Thanks for the introduction. Thanks for coming. Flavour of the work related to the notion of a Future Internet.
The Internet is a network of networks, created in the 60s2 billion usersrevenue to reach €229 billions by 2014
10 lines of code per day because its very hard to get rid of bugs in software
The approach we take is based on brokering which I will explain with a metaphor
Media: BBC programmes, BBC MUSIC, New York Times, Last FMGeographic: US Census, Airports, GeoNamesPublications: ACM, IEEE, RAE 2001User Generated Content: Flickr, Revyu.com, swdogfood from conferencesGovernment: UK Postcodes, UK Government, Ordnance SurveyLife Sciences: PubMed (medical publications), Gene ontologyCross Domain: DBPedia (semantic data version of wikipedia), Freebase bought by Google; Soon we won’t be able to draw the mapSo here is the latest map of all this semantic data. You can see we have 25 billion machine readable statements here in the areas of:
The UK government data.gov.uk site, initiated by Gordon Brown in early 2010 when he was Prime Minister, continued under David Cameron. Gordon Brown: closing down 13,000 government websites David Cameron: transparency engagement of citizens
Nearly 7000 datasets “UK taxpayers paid for this data so UK citizens and businesses should get it for free”Every UK government department is being pushed to release its data online. Gordon Brown: can close down 13000 government websitesDavid Cameron: increase transparency, engagement
So how do we link to this wealth of data?We have our own repository of service descriptions within the cloud. We are the first and still only service repository in this space. The are created using a variety of tools. Note that when creating our descriptions we can rely on existing descriptions in the cloud. In the same way as one web page can point to another to expand a description.
As well as creating descriptions within the cloud we support
The creation of services which consume and produce semantic data.
We also support the management and use of ‘standard’ services
Which can produce data for this large semantic cloud
Now I come to a first of 3 examples. This one from a recent project. Imagine that you are moving to a new area and you are looking for a house. You would be concerned with
Depending on your circumstances
Within one of my projects (soa4all) we have developed an iPhone App to support this. Its available in the store and called the soa4all real estate finder
Mulberry school and others
Services over public data (to the singers in the virtual choir)Service broker is like the conductor. Services are published in our broker. An engine translates between user actions and details of invoking services (each service may have its own idiosyncratic way of being invoked)User interacts with the iPhone Appdiscovery based on user preferences and location -> services are available Services are not fixed (like singers for each performance). adding more for crime statistics also based on public data.
SAP 4th largest software producer in the world by revenue Microsoft, IBM and Oracle. 109,000 customers 120 countriesSAP with 12.46B euro of revenue Very much interested in the Internet of the Future
Business-to-Business (B2B) Gateways integrate data from back-end systems enabling information exchange across trading partnersPutting software and applications in the cloud (nonlocal machine)Service provider: creates the service – may be a software companyServicehoster: puts it on a machine and makes it available online. Alludes to what is known as the cloudService Gateway: responsible for ensuring interactions between businesses work on a technical level. Connecting many services togetherService Aggregator: puts together external services to support clientsService Broker: a front desk that negotiates with consumersService Channel Maker: create sector specific channels for services e.g. for banking one can have mobile banking, internet banking, retail banking, channels can include a webportal, mobile, other examples, eBay, Amazon services Itunes is an example of a channel (which is SAP software underneath)
USDL isthegluebetweentheparts
The EU funding agencies under the framework 6 and 7 programmes, my collaborators in these large EU proejcts. All my colleagues in Kmi – there are only a handful of labs in Europe where this type of work could be supported. Kmi has a unique atmosphere for which I am gratefulAlso my colleagues in the Open Media Unit the BBC and ResonanceFinally my staff and postgrads 10 researchers with 8 nationalities none english. Also Harriett and Jacek for there efforts on the slides.
