CRE652 Processor Architecture Making it Trustworthy Trustworthy Computing and Branch Prediction
Aniketos platform : Design of a trustworthy composite service
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Summer SOC July 2 nd – July 7 th Aniketos platform: Design of a trustworthy composite service 1
description
Aniketos platform : Design of a trustworthy composite service. Summer SOC July 2 nd – July 7 th. Reference scenario for the demo. - PowerPoint PPT Presentation
Transcript of Aniketos platform : Design of a trustworthy composite service
Summer SOCJuly 2nd – July 7th
Aniketos platform:Design of a trustworthy composite
service
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Summer SOC 2012
A service provider wants to offer a service that takes in input the geographical position of a user and shows in a webpage a set of information: A map showing the position Weather information Point of interests in the surroundings
The service provider wants the service to be trustworthy, so he asks the service designer to exploit the tools made available through the Aniketos platform
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Reference scenario for the demo
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The trustworthiness value is evaluated by the Trustworthiness Prediction module and is a combination of: Cognitive trust of the user, based on the service and service
provider reputation. Non-cognitive trust, based on objective and measurable properties
of the service such as QoS attributes (reliability, performance, availability)
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About trustworthiness in Aniketos…
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Service Composition Framework (SCF)
The SCF is a design time module available in the Aniketos environment allowing a service designer to build executable composition plans
To use the framework the service designer must be authenticated
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SCF: get started with BPMN modelling
Once authenticated, the service designer can start the BPMN modelling
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BPMN model of InfoService
From the description of the service in terms of functionality, the service designer decides to use different atomic services and compose them according to the BPMN drafted in the SCF editor
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The service designer is in charge of designing a composite service with a specific requirement on trusthworthiness value
The trustworthiness requirement is expressed as a consumer policy written in ConSpec grammar
The file location is included in an extensionElements tag in the xml representing the BPMN
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BMPN annotated with trustworthiness requirement
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An excerpt of the resulting xml for the annotated BPMN is shown below:
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Annotated BPMN
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To make the composition plans the SCF has to bind real web services to the service tasks in the BPMN
The binding process entails: Service discovery using the ServiceType as search filter
The SCF shows the operations offered by the web services matching the request based on the ServiceType
Selection of the specific operation the service designer wants to use in order to compose the InfoService
If the same operation is offered by different atomic services the service designer will see just one operation
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Service discovery and selection of the service operation
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Discovery and selection: GeoCoding example (1/2)
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and selects getCoordinates ( )
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Discovery and selection: GeoCoding example (2/2)
The service designer discovers operations offered by GeoCoding type services ( )
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The service designer isn’t aware of how many web services offer that operation, it’s the SCF which will bind the different services to the service task when making composition plans
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Creation of composition plans
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Once the service designer has selected an operation for each service task the SCF is ready to create the composition plans
When the service designer clicks on “Create composition plans” button, the SCF shows a set of functionally valid composition plans
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The SCF has created 12 composition plans: this is explained by the number of web
services offering the same operation: Geocoding type: bound to 2 web services PointOfInterest type: bound to 3 web services WeatherForecast type: bound to 1 web
services Map type: bound to 2 web services WebPageInfoCollector type: bound to 1 web
services Thus the number of composition plans
is 2 X 3 X 1 X 2 X 1 = 12
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Composition plans created by the SCF
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The composition plans ensure functionality but do not consider the trustworthiness requirement
The composition plans have to be checked against the requirements specified for the trustworthiness value
This check is performed by the Secure Composition Planner Module which receives the composition plans from the SCF and returns those ones that fulfill the trustworthiness requirement
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Selection of trustworthy composition plans
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The SCPM invokes the Trustworthiness prediction module to evaluate the trustworthiness value for the set of composition plans received from the SCF
The trustworthiness value of the composite service is evaluated using the weakest link principle The Trustworthiness module evaluates the trustworthiness value
for each service taking part in the composition The lowest value is returned as the trustworthiness value of the
composite service
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Trustworthiness prediction for composite services
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When the service designer clicks on “Verify All” button the SCPM selects the composition plans that fulfils the trustworthiness requirement
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Trustworthy composite services
In order to visualize the Trustworthiness value of the composition plans the service designer selects “Order By” Trustworthiness and clicks on “Order/Rank” button
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Last steps: upload and deploy
The service designer selects one of the trustworthy composition plans and can Upload the BPMN to an Activiti
Engine Deploy it to a web application
server
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