Outline

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Outline

• Introduction
• An Appliance Computing World
• The Architecture
• Current Implementation
• Evaluation
• Research Agenda
• Related Work
• Conclusion

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1. Introduction

• Digital appliance
• to be easier-to-use, more-powerful
• be made possible by infrastructure services
• handheld Web-browsers, TiVoTM
• to leverage the computational power, network the
  bandwidth, content, aggregate user base of
  service in the infrastructure
• infrastructure enabled
• Problem
• high prices, many features and complex function,
  many steps for device using( Installing,
  configuring, learning )
• Digital appliances are designed to be easier to
  use and more powerful
• more difficult to use and have too many features

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2.An Appliance Computing World

• ADS
• the goal to identify principles
• bring devices to the forefront
• minimize the number of device features
• place functionality in the network infrastructure
• Vision
• An appliance computing world is one in which
  people move data effortlessly among artifacts to
  accomplish a variety of simple and advanced tasks
• ADS project
• making observations on attributes that are
  inherent in an appliance Computing World
• identifying the principles that underlie these
  attributes
• building a framework based on these principles

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2.1 Bring device to the forefront

• If appliance computing is to become a reality
• People find it easier to use concrete artifacts
  to move data
• Attribute 1
• People move data using concrete artifacts
• problem
• Digital devices are hard to use
• users to perform too many steps for their works

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2.1 Bring device to the forefront

• Principle 1
• Bring devices to the forefront
• allows the user to reason about the source and
  destination of data rather than the path I must
  take so that data can be moved seamlessly across
  artifacts
• Ubiquitous Computing
• The traditional notion of a file should become
  invisible to the user

Black box
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2.2 keep devices simple

• Attribute 2
• Devices are simple, single-purpose appliances
• push more functionality onto the devices
• devices have not made tasks any easier
• make a device easier to use
• user has to learn how to operate
• Example
• Voice command on cell phones VS picture
  previewing on digital cameras
• Principle 2
• Keep the number of user-controllable features
  users must learn to operate a device to a minimum

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2.3 Place S/W in the infrastructure

• What will people be able to do with these simple
  devices?
• use these devices to perform the same tasks as
  their traditional
• Attribute 3
• People perform a variety of traditional tasks, as
  well as a new set of advances tasks with their
  devices

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2.3 Place S/W in the infrastructure

• where dose the functionality lie to perform the
  high-level tasks the users demand?
• users PC
• shielding the user form the PC experience
• does not relieve the user of other PC experience
• Internet infrastructure
• Refer to the deployed collection of H/W and S/W
  accessible directly or indirectly via an Internet
  programmatic interface
• the advantage of fully relieving the user of the
  PC experience

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2.3 Place S/W in the infrastructure

• Principle 3
• Place the software required to accomplish tasks
  in the Internet infrastructure
• Internet infrastructure
• Advantage
• logically centralized S/W makes upgrades and
  administration simpler
• availability and reliability
• existing Internet services and achieve economies
  of scale for the services provided
• facilitating a move towards simpler devices with
  simpler user interface
• be used to support very inexpensive and very
  small devices

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2.4 Appliance Data Services

• ADS framework implements the principles of
  appliance computing
• Bring devices to the forefront
• Keep the number of user-controllable features on
  devices to a minimum
• Place the software required to accomplish tasks
  in the network infrastructure
• create digital information
• other principles and challenges
• designing easy-to-use device
• system user interface

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3. The Architecture
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3. The Architecture

• basic data unit ( userid, command-tag, data )
• reason
• Application selection( command-tag )
• names the high-level application
• alone is not sufficient to define the application
• Access control( userid )
• The system needs some identifier to attach
  credentials to the request
• Other service features
• billing, security, personalization

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3. The Architecture

• Scenario
• a user named Jane posting pictures and captions
  to her online photo album
• she uses her digital camera to take pictures and
• her PDA to jot down descriptions of her pictures
• She goes to an ADS Access Point
• Jane logs in by inserting her SmartCard and
  entering her PIN,
• Then selects the photoalbum application
• She transfers using the IR ports on her digital
  camera and PDA

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3.1 Data Receive

• data is taken from various devices by the Access
  Point
• transferred to the next stage once a complete (
  userid, command-tag, data )

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3.1.1 Access Point

• consists of necessary H/W and S/W to receive data
  from appliances
• H/W IR transceivers, RF basestations
• S/W is made up of device adaptors
• The Access Point can be is implemented Commodity
  PC and a special-purpose network appliance
• scenario
• SmartCard reader -gt userid
• touch-screen monitor to display -gt comman-tag
• IR receiver and S/W -gt data

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3.1.1 Access Point

• existing of many devices
• a single-purpose -gt increase in the variety of
  devices
• standardization need
• use each other protocols
• Role
• Isolates device heterogeneity to a single
  architectural component
• Key challenge
• extensibility in supporting devices and protocols
• make adding support for new devices simple

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3.1.2 Aggregator

• adding support for new devices is to make the
  Access Point stateless
• to have a separate component or library within
  the Access Point
• to separate the state management completely by
  placing hard state in another architectural
  component Aggregator
• The functional role
• gather data sent from the Access Point
• send the data to the next stage once all pieces
  of the triple

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3.1.2 Aggregator

• reason of separate architectural component
• Robustness
• can be arbitrarily restarted as necessary
• Ease of deployment
• Access point must be deployed anywhere users want
  to use ADS
• Do not require disks and extra S/W to manage
  state make deployment easier and more
  cost-effective
• Evolvability
• Authentication
• Aggregator becomes a convenient place to
  implement authentication modules
• Role
• Simplifies adding support for new devices in a
  robust, easy-to-deploy way

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3.2 Application Control

• The userid and command-tag received from the Data
  Receive stage are used to determine the desired
  application

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3.2.1 Command Canonicalizer

• Role
• Facilitates the design of devices with simple
  user interface
• Canonicalizer
• converting the command-tag from its original data
  type to plaintext
• Free the device designers

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3.2.2 Template Database

• Template
• Definition
• applications behavior by describing the data
  required for a given application and specifying
  the services to invoke on the data
• Template database
• Minimizing device configuration
• Supporting devices with non-extensible user
  interface
• Role
• Minimizes device configuration

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3.2.2 Template Database

• application templates and the command-tag
  mappings
• configured for a particular user independently of
  the users device
• non-extensible user interface
• be mapped to the appropriate application template
• provides a level of indirection between
  application selection and application
  specification
• to separate the concerns of users of ADS
  applications and creators of ADS application
  templates
• a third-party template provider can easily and
  effectively restrict access to the templates
• Upgrading applications or adding new ones is
  simple
• Application templates give a large degree of
  flexibility

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3.2.3 Dataflow Manager

• sends the template and all the data to the
  Services Execution stage
• allows users to input the data from different
  devices
• Role
• Coordinates data input by the user

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3.3 Services Execution

• application dispatcher invokes the services
  specified in the application template on the data
  it receives.
• ADS employs modular composable services
• facilitates the building of applciation
• flexible
• reusable

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4 Current Implementation

• access Point is discussed separately form the
  remaining components
• do not logically reside in the centralized
  network infrastructure
• be likely to be deployed as publicly-accessible
  Web kiosks or as appliances within peoples home

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4.1 Access Point

• Extensibility
• Easy to support new device
• Making each device adaptor autonomous

File system
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4.1.1 Device Adaptors

• autonomous, stateless device adaptors
• Interact directly with the particular devices or
  protocols
• autonomous
• is achieved by eliminating the programmatic
  interface between the adaptors and forwarder
• using the file system
• Forwarder
• Forwarding data received by the adaptors on to
  the aggregator

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4.1.2 Forwarder

• Detect a new file in the shared directory, it
  sends the data to the Aggregator using the POST
  method of HTTP
• Using HTTP POST
• provides more flexibility
• Allows the Access Point to send any metadata it
  receives from the device without knowing what
  information the Aggregator can handle
• Facilitate backward compatibility

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4.1.3 Status

• Access Point runs on an IR-equipped, commodity PC
  running Windows 2000
• Palm, WinCE, and other devices that support the
  IR-FTP protocol
• HP CapShare handheld scanner, HP digital cameras,
  and other devices that support the HP JetSend IR
  protocol (IR)
• CardScan business card scanner (parallel port or
  USB)
• Telephones TellMe menu- and voice-driven
  inter-faces allow users to login and select
  commands using any telephone.

HP CapShare
CardScan
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4.2 Infrastructure Components

• One or more Linux PCs
• Built on the Ninja service framework
• developed at UC Berkeley
• goal of its services
• automatically gain Reliability, fault
  tolerance, scalability
• constraint
• Inherit two method
• init(), destroy()
• independently restartable and replicable services
  that communicate via JAVA RMI
• each of the components exports an HTTP interface
  to the outside world

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4.2 Infrastructure Components
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4.3 Application

• Web Photo Album
• Guestbook

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4.3.1 Web Photo Album

• The user conducts the following steps to create a
  Web-based photo album using a digital camera
• Operation
• 1. Take pictures with a digital camera
• 2. Visit a Web Page to login and select the photo
  album application

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4.3.1 Web Photo Album

• 3. Transfer the pictures by pointing the cameras
  IR transceiver at an IR-equipped Access Point
• 4. produces a thumbnail stores the file enter
  descriptions of each photo via a Web page that
  displays the pictures received by ADS
  (alter-natively, the application can be designed
  to accept captions sent via IR using a PDA)

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4.3.1 Web Photo Album

• 5. click "add to photo album" and view the
  published page

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4.3.2 Guestbook

• scenario
• The attendee looks into a Webcam mounted on the
  kiosk and presses a button to take a picture
• the application requests the attendee's business
  card and displays the following options
• type your contact information
• place your business card in the CardScan business
  card scanner
• beam your electronic business card using a Palm
  or WinCE device
• the attendee verifies that the picture looks
  right and the business card information is
  correct, then clicks a button to add the entry to
  the conference attendee list

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5. Evaluation

• evaluation
• how well the implementation meets the stated
  principles of out appliance computing vision
• Bring devices to the forefront
• Minimize the number of device features
• Place functionality in the network infrastructure
• how easy it is for developers to build
  applications on the framework

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6. Research Agenda

• Integrating more infrastructure services
• Infrastructure-centric approach
• Leverage existing infrastructure services
• Current service Geocities, PhtoPoint
• Exploration into Smart Space environments
• The Interactive Workspaces Project at Stanford
• Involve installing a production version of the
  ADS framework in the IRoom
• Guestbook application
• Conveying status and error information

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7. Related Work

• The Portolano Project at the University of
  Washington
• appliance computing world reality
• user interfaces, service deployment and resource
  discovery
• The Sony Computer Science Laboratory
• The Pick-and Drop and InfoStick project
• user find it easier to deal with concrete
  artifacts
• The Augmented Surfaces project
• How the users mobile devices can be integrated
  into the current computing environment
• transformational proxies
• wireless protocol gateway

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8. Conclusion

• Appliance Computing World
• Everyday users move data seamlessly and
  effortlessly among handheld and
  infrastructure-attached artifacts
• The goal of this project
• identified three principles for realizing this
  vision
• implemented a testbed for affirming their validity