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Data marketplaces: core models and
concepts
Hong-Linh Truong
Distributed Systems Group,
Vienna University of Technology
[email protected]://dsg.tuwien.ac.at/staff/truong
1ASE Summer 2014
Advanced Services Engineering,
Summer 2014, Lecture 6
Advanced Services Engineering,
Summer 2014, Lecture 6
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Outline
Data marketplaces
Description models
Data agreement exchange models and
architectures
Data contract model and evaluation
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Data service unitData service unit
3
Recall – data service units in
clouds/internet
datadata
Internet/CloudInternet/Cloud
Data service unitData service unit
People
data
Data service unitData service unit
Things
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data data
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Data-as-a-Service – service modelsData-as-a-Service – service models
Recall – data as a service
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Storage-as-a-Service
(Basic storage functions)
Storage-as-a-Service
(Basic storage functions)
Database-as-a-Service
(Structured/non-structured
querying systems)
Database-as-a-Service
(Structured/non-structured
querying systems)
Data publish/subcription
middleware as a service
Data publish/subcription
middleware as a service
Sensor-as-a-ServiceSensor-as-a-Service
Private/Public/Hybrid/Community CloudsPrivate/Public/Hybrid/Community Clouds
deploy
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Data marketplaces
More than just DaaS
DaaS focuses on data provisioning features
Stakeholders in data marketplaces
Multiple data providers and consumers
Marketplace providers
Marketplace authorities
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Technical services, protocols,
mechanisms in data marketplaces
Multiple DaaS provisioning
Access models and interfaces
Complex interactions among DaaS providers,
data providers, data consumers, and
marketplace providers
Data exchange as well as payment
Complex billing and pricing models
Market dynamics
Service and data contracts
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DAAS DESCRIPTION MODEL
Some important issues
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DATA AGREEMENT EXCHANGE
DATA CONTRACT
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Description model for DaaS (1)
State of the art:
Providers have their own way to describe DaaS,
mainly in HTML
Existing service description techniques are not
adequate in supporting description for DaaS
Problems
Service and data discovery cannot be done
automatically
On-demand data integration, service integration, and
query optimization cannot be supported well.
Service/data information and DaaS engineering
cannot be tied.ASE Summer 2014 8
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Description Model for DaaS (2)
Which levels must be covered?
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Data
items
Data
items
Data
items
Data resourceData resource
Data
assets
Data resourceData resource Data resourceData resource
Data resourceData resourceData resourceData resource
Consumer
Consumer
DaaS
Here
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Description model for DaaS – types
of information
Which types of information must be covered?
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Quality of
dataOwnership
PriceLicense ....
Service
interfaceService
licenseQuality of
service ....
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DEMOS – a description model for
Data-as-a-Service
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See prototype:
http://www.infosys.tuwien.ac.at/
prototype/SOD1/demods/
Quang Hieu Vu, Tran Vu Pham, Hong
Linh Truong,, Schahram Dustdar,
Rasool Asal: DEMODS: A Description
Model for Data-as-a-Service. AINA
2012: 605-612
Quang Hieu Vu, Tran Vu Pham, Hong
Linh Truong,, Schahram Dustdar,
Rasool Asal: DEMODS: A Description
Model for Data-as-a-Service. AINA
2012: 605-612
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Description model and data
marketplaces
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DEMODS – prototype (1)
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DEMODS – prototype (2)
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WHICH TYPES OF DAAS INFORMATION
ARE DYNAMIC? AND THEIR IMPACT ON
DESCRIPTION MODELS?
Discussion time
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Exchange data agreement (1)
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DaaS
Consumer
DaaS
Sensor
DaaS
Consumer DaaS provider Data
provider
How do they interact w.r.t. data concerns?
How do their data agreements look like?
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Exchange data agreement (2)
Lack of models and protocols for data
agreement in data marketplaces
Constraints for data usage are not clear
Inadequate data/service description → hindering data
selection and integration
Existing techniques are not adequate for
dynamic data agreement exchange in data
marketplaces
Need generic exchange models suitable for different
ways of data provisioning in data marketplaces
Need generic exchange models suitable for different
ways of data provisioning in data marketplaces
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Data Agreement Exchange as a
Service (DAES)
Metamodel for data agreement exchange
Techniques for enriching and associating data
assets with agreement terms
Interaction models for data agreement exchange
Hong Linh Truong, Schahram Dustdar, Joachim Götze, Tino Fleuren, Paul Müller, Salah-Eddine Tbahriti, Michael Mrissa,
Chirine Ghedira: Exchanging Data Agreements in the DaaS Model. APSCC 2011: 153-160
Hong Linh Truong, Schahram Dustdar, Joachim Götze, Tino Fleuren, Paul Müller, Salah-Eddine Tbahriti, Michael Mrissa,
Chirine Ghedira: Exchanging Data Agreements in the DaaS Model. APSCC 2011: 153-160
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Metamodel for data agreements
Different
category of
agreements
Licensing,
privacy, quality
of data
Extensions
Languages
Different types
of agreements
Different
specifications
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Associating data with data
agreements
Solutions
(a) directly inserting agreements into data assets
(b) providing two-step access to agreements and data
assets
(c) linking data agreements to the description of DaaS
(d) linking data agreements to the message sent by
DaaS
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Possible interaction models for data
enriched with data agreements
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DAES – conceptual architecture
Using URIs to identify agreements
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DAES – managed information
Specific applications: agreement creation, agreement validation,
agreement compatibility analysis, agreement management
Specific applications: agreement creation, agreement validation,
agreement compatibility analysis, agreement management
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Illustrating examples – insert
agreement into data asset
A pay-per-use consumer uses dataAPI of DaaS
search for data
The consumer pays the use APIs
Each call can return different types of data
Example of
searching people
But a strong consequence
for data service engineering
techniques: dealing with
elastic requirements!
But a strong consequence
for data service engineering
techniques: dealing with
elastic requirements!
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Illustrating examples – link
agreements to geospatial data Domain-specific DaaS: different agreements for different data requests
Vector data of geographic features via Web-Feature-Service (WFS)
Terrain elevation data via Web-Coverage Services (WCS)
Domain-specific DaaS: different agreements for different data requests
Vector data of geographic features via Web-Feature-Service (WFS)
Terrain elevation data via Web-Coverage Services (WCS)
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Illustrating examples – link
agreements to geospatial data
Consumers can interpret and
reason if the data can be
used for specific purposes
Consumers can interpret and
reason if the data can be
used for specific purposes
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Illustrative examples – develop an
app for policy compliance (1)
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Illustrative examples – develop an
app for policy compliance (2)Configuration
Results
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HOW DOES NEAR-REALTIME DATA IMPACT
ON DATA AGREEMENT EXCHANGE?
Discussion time
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Data contract
How to specific data contract?
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Data
items
Data
items
Data
items
Data resourceData resource
Data
assets
Data resourceData resource Data resourceData resource
Data resourceData resourceData resourceData resource
Consumer
Consumer
DaaS
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Data contracts
Give a clear information about data usage
Have a remedy against the consumer where the
circumstances are such that the acts complained
of do not
Limit the liability of data providers in case of
failure of the provided data;
Specify information on data delivery,
acceptance, and payment
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Data contracts
Well-researched contracts for services but not
for DaaS and data marketplaces
But service APIs != data APIs =! data assets
Several open questions
Right to use data? Quality of data in the data
agreement? Search based on data contract? Etc.
➔ Require extensible models
➔ Capture contractual terms for data contracts
➔ Support (semi-)automatic data service/data selection
techniques.
➔ Require extensible models
➔ Capture contractual terms for data contracts
➔ Support (semi-)automatic data service/data selection
techniques.
Hong-Linh Truong, Marco Comerio, Flavio De Paoli, G.R. Gangadharan, Schahram Dustdar, "Data Contracts for
Cloud-based Data Marketplaces ", International Journal of Computational Science and Engineering, 2012 Vol.7, No.4,
pp.280 - 295
Hong-Linh Truong, Marco Comerio, Flavio De Paoli, G.R. Gangadharan, Schahram Dustdar, "Data Contracts for
Cloud-based Data Marketplaces ", International Journal of Computational Science and Engineering, 2012 Vol.7, No.4,
pp.280 - 295
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Study of main data contract terms
Data rights
Derivation, Collection, Reproduction, Attribution
Quality of Data (QoD)
Not mentioned, Not clear how to establish QoD metrics
Regulatory Compliance
Sarbanes-Oxley, EU data protection directive, etc.
Pricing model
Different models, pricing for data APIs and for data assets
Control and Relationship
Evolution terms, support terms, limitation of liability, etc
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Most information is in human-readable formMost information is in human-readable form
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Data contract study
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Hong-Linh Truong, Marco Comerio, Flavio De Paoli, G.R. Gangadharan, Schahram Dustdar, "Data Contracts for
Cloud-based Data Marketplaces ", International Journal of Computational Science and Engineering, 2012 Vol.7, No.4,
pp.280 - 295
Hong-Linh Truong, Marco Comerio, Flavio De Paoli, G.R. Gangadharan, Schahram Dustdar, "Data Contracts for
Cloud-based Data Marketplaces ", International Journal of Computational Science and Engineering, 2012 Vol.7, No.4,
pp.280 - 295
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Developing data contracts in cloud-
based data marketplaces
Follow community-based approach for data
contract
Propose generic structures to represent data
contract terms and abstract data contracts
Develop frameworks for data contract applications
Incorporate data contracts into data-as-a-service
description
Develop data contract applications
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Community view on data contract
development
Community users can develop:
Term categories, term names, values, and units
Rules for data contracts
Common contract and contract fragments
Community users =!
novice users
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Representing data contract terms
Contract term: (termName,termValue)
Term name: common terms or user-specific terms
Term value: a single value, a set, or a range
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Structuring abstract data contracts
Concrete data contracts can be in
RDF, XML or JSON
genera
tes
Use Identifiers and
Tags for identifying
and searches
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Development of contract
applications
Main applications:
Data contract compatibility evaluation, data contract
composition
Some common steps
Extract DCTermType in TermCategoryType
Extact comprable terms from all contracts,
- e.g., dataRight: Derivation, Composition and Reproduction
Use evaluation rules associated with DCTermType
from rule repositories
Execute rules by passing comparable terms to rules
Aggregate results
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Evaluating Data Contracts
Goal
Check the quality and reputation of a data contract
We can check data contracts using quality of
data metrics
Timeliness, Completeness, Reputation, Consistency
metrics
Examples
Free-per-use but cost = 100EUR
Missing „data accuracy“ concern
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Data Contract Compatibility
Goal
If multiple data contracts are compatible with the
consumer needs
The consumer requires multiple data associated with
different contracts
Contract compatibility
Matching contract terms
Evaluating contract term compatibility and
completeness w.r.t. application needs
Making decision in using data
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Example of contract compatibility
evaluation
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Conceptual architecture for contract
management and evaluation
Prototype
RDF for representing term categories,
term names, term values, units
Allegro Graph for storing contract
knowledge
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Illustrating examples
A large sustainability monitoring data platform
shows how green buildings are
Real-time total and per capita of CO2 emission
of monitored building
Open government data about CO2 per capita at
national level
We created contracts from
Open Data Commons Attribution License
Open Government License
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Existing
common
knowledge
about Open
Data
Commons
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Step 2: provide OpenBuildingCO2
OpenBuildingCO2 by
modifying quality of
data and data right
OpenBuildingCO2 by
modifying quality of
data and data right
OpenGov for
government data
OpenGov for
government data
Data contract for green building dataData contract for green building data
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Experiments – composing data
contract terms
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CAN WE AUTOMATICALLY GENERATE
DATA CONTRACTS FOR NEAR-REALTIME
DATA?
Discussion time
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Exercises
Read mentioned papers
Examine existing data marketplaces and write
DEMODS-based specification for some of them
Develop some specific data contracts for open
government data
Work on some algorithms for checking data
contract compatiblity
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Thanks for your attention
Hong-Linh Truong
Distributed Systems Group
Vienna University of Technology
http://dsg.tuwien.ac.at/staff/truong
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