Component Framework for Consumer Electronics Middleware

1
Component Framework for Consumer Electronics
Middleware

• Location TU/e (HG 5.95)
• SAN Weekly presentation
• Date 10 September 2004
• Johan Muskens
• J.Muskens_at_tue.nl

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Outline

• Introduction
• Background
• Motivation
• Requirements
• Component Model
• Life-Cycle
• Component Packaging
• Run Time Architecture
• Executable Component
• Run Time Environment
• Download Framework
• Resource Management Framework
• Discussion

3
Background

• Research is part of the following projects
• Robocop (2001 - 2003)
• Define an open, component-based framework for the
  middle-ware layer in high-volume consumer devices
  (robustness/reliability, upgrading/extension, and
  trading)
• Space4U (2003 - 2005)
• Extend and validate the Architecture
• Fault Management
• Power Management
• Terminal Managment

4
Motivation for Component Based Development

• Aim
• Increase productivity (Reduce Time to Market) by
  making reuse easier.
• How
• Reuse at component level
• Easy composition (and modification of a
  composition)
• Interaction through well defined interfaces
• Dependability on interfaces in stead of
  components
• Composition at run-time (run-time upgrading)
• Component Trading
• Component repositories

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What is a Component Model?

• A component model specifies the standards and
  conventions imposed on developers of components.
  A component model addresses (at least) the
  following
• the set of component types, including their
  interfaces,
• the allowable patterns of interaction
  (component-component and component-run-time
  interaction) in particular the binding
  mechanism.
• Component Model Rules

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What is a Component Framework?

• A generic software architecture (described in
  terms of component interfaces, composition
  mechanisms and composition rules) together with a
  set of generic software components that may be
  used to realize specific software architectures.
• Component Framework
• Tools Generic Architecture Generic components

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What is an Architecture?

• The fundamental organization of a system embodied
  in its components, their relationships to each
  other, and to the environment, and the principles
  guiding its design and evolution.

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What is offered by Component Frameworks?
blue mandatory
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Existing Component Frameworks

• (D)COM
• EJB
• .NET
• CORBA
• Koala
• PECOS
• AutoComp
• Robocop
• ...

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Focus in CE Domain
red focus CE domain
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Evaluation Existing Component Frameworks
yellow focus CE domain
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Outline

• Introduction
• Background
• Motivation
• Requirements
• Component Model
• Life-Cycle
• Component Packaging
• Run Time Architecture
• Executable Component
• Run Time Environment
• Download Framework
• Resource Management Framework
• Discussion

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Component Life-cycle
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Component Packaging

• A Robocop component is a set of possibly related
  models
• RC P(M) x P(M x M x T)
• M EM ? BM ? RM ? ...
• T MODELTYPE x
• MODELTYPE x
• NAME

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Component Packaging (Motivation)

• Trading
• Different views for different stakeholders
• Executable for consumer
• Source code, documentation for developer
• ...
• Desirable to trade more than binaries
• Analysis
• During Development
• Simulations / Analysis for feasibility tests
• At Run Time
• Admission tests during downloading of components

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Component Packaging (Example)
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Outline

• Introduction
• Background
• Motivation
• Requirements
• Component Model
• Life-Cycle
• Component Packaging
• Run Time Architecture
• Executable Component
• Run Time Environment
• Download Framework
• Resource Management Framework
• Discussion

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Runtime Architecture

• Run-time view of a terminal
• Application Layer
• Applications
• Middleware Layer
• Run Time Environment
• Executable Components
• Platform Layer
• OS Abstraction
• Device HW drivers

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Executable Component

• Executable Components implement a number of
  Services
• Executable Components are instantiated in OS
  terms
• Static in process (LIB)
• Dynamic in process (DLL)
• Dynamic out process (EXE)
• Executable Components have a fixed entry point
  for
• Registration to Run Time
• Retrieving Service Manager
• Service Manager is used for instantiating services

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Services

• Services offer their functionality through a set
  of ports (named interfaces)
• Services have explicit dependencies required
  ports (named interfaces)
• An Interface is a set of operations
• Services are instantiated at Run Time
• Service Class in object oriented programming
• Service Instance is an entity with its own data
  and a unique identity
• Service Instance Object in object oriented
• programming

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Executable Component (Example)
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Run-time Environment

• Responsibility
• Registration of components and services
• Handle requests for services instances (and
  services managers)
• Offer support for QoS (Optional)
• Implementation
• Three tables
• Association between Component (ID) and Location
• Association between Component (ID) and Service
  (ID)
• Complies relation between Services (IDs)

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Run Time Environment (Example Registry Content)
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Run Time Environment (Example Registry Content)

• This graphically depicts the contents of the
  registry on previous slide

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Download Framework

• Responsibility
• Transfer Robocop components from repository to a
  target terminal.
• Implementation
• 5 roles together accomplish the download
• Initiator
• Locator
• Decider
• Repository
• Target (needs to be on the terminal)

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Download Framework (Key Features)

• Low Resource Footprint on Target
• Only the target role needs to be resident on the
  target terminal
• Supports external initiation of download
• Initiator can be resident on a external server
• Supports decision on suitability of a component
  for a specific target
• Decider role

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Download Framework (Procedure)
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Download Framework (Example Deployment)
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Resource Management Framework

• Resource Management using the following Quality
  Aware Entities
• Quality Manager
• Maintain global quality.
• Assign Negotiate budgets
• Resource Manager
• Setting Accounting Enforcing budgets
• Quality Chief (application of service)
• Interact with Quality Manager (Negotiation)
• Resource Chief
• Interact with Resource Manager
• Isolate platform dependent issues

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Resource Management Framework (Overview)

Application Layer

• Quality Manager and Resource Manager are part of
  the RRE.
• Quality Aware entities implement the
  IQualityChief interface
• Services
• Applications
• Resource Chiefs are part of the OS
• In Robocop the linux kernel has been patched

Platform Layer
Middleware Layer
QoSManager
RRE
Platform Layer
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Resource Management Framework (API)

• Quality Manager
• addApplicationQM / removeApplicationQM
• reviewSystemQuality
• assessFeasibility
• Resource Manager
• checkFeasibility
• setConfiguration
• setBudgetUser / removeBudgetUser
• getMonitoringInfo

• Quality Chief
• getQualityInfo
• setQualityLevel
• getBudgetID
• Resource Chief
• createBudget / removeBudget
• getStatusBudget
• getMonitoringInfo
• ...

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Resource Management Framework (Negotiation)
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Resource Management Framework (Setting
Configuration)
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Resource Management Framework (Change
Configuration)
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Outline

• Introduction
• Background
• Motivation
• Requirements
• Component Model
• Life-Cycle
• Component Packaging
• Run Time Architecture
• Executable Component
• Run Time Environment
• Download Framework
• Resource Management Framework
• Discussion

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Discussion

• Robust and Reliable Operation
• Explicit dependencies between services
• Resource Management Framework
• Fault Management Framework (Space4U)
• Integrity Management Framework (Space4U)

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Discussion

• Low Resource Footprint
• Minimal Run Time
• Service registration instantiation only
• Download Framework, Resource Management
  Framework, ... are all optional
• Computation intensive part (e.g. deciding and
  customizing)of Download Framework can be done
  outside the terminal
• Minimal Communication overhead
• Interfaces use vtables this requires one
  additional pointer dereference per method
  invocation.
• No interpreted language

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Discussion

• Upgrading and Extension
• Applications and services are dependent on
  (binary)interfaces not on services.
• New components can be downloaded and registered
  at run-time (Download Framework)

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Discussion

• Trading
• Download Framework enables transfer of components
• Different models address the different concerns
  of the different stakeholders