Context-Aware Communication for People

Telephone amazing technology has helped communication from the 1870s

• could ring at most inappropriate and inconvenient times and be a source of annoyance

• the callee does not have a choice and is forced to hear the ringing by the caller, even if the callee does not answer the phone.

Making the phone not ring, 2005, H. Schulzrinne, Columbia Univ.

• presentation at the Internet2 Spring Meeting

Context-aware communication

• Make the phone not ring except in an appropriate manner

• The Phone rings at the callee situations

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Evolution of VoIP

PRID : Rich Presence IDautomatically derived from

sensors: physical presence, movementelectronic activity: calendars

Provide watchers with better information aboutthe what, where, how of presentities

1. Routing

Routing : Messages or voice calls can be routed to the appropriate destination

• The phone in the right room can ring by call forwarding :

who they are with, where they are, what they are doing, what the time it is

• Augmenting device-mediated communication with context information enrich user interaction.

Architectural Considerations for Scalable, Secure, Mobile Computing with Location Information, 1994, Mike Spreitzerm Xerox Palo Alto

Ubiquitous Message Delivery at Xerox PARC (UMD, 1994)

• An autonomous system for both sensing and communication acts

• User location - active badges, keyboard input activity, and explicit commands

• Text delivered “at the soonest acceptable time via the most appropriate terminal near the recipient”, waited for a suitable situation or terminal to be available

• User agent process : User location and the user’s policy regarding message

delivery were maintained

• Terminal agents : manage the policy of outputting messages on terminals

• No user-oriented heuristics for deciding acceptable times and appropriate terminals

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2. Addressing

Addressing : contextually appropriate people (mailing lists and shared spaces)

• Entities can be addressed based on their context instead of their unique identifier or names

A Conceptual Framework and a Toolkit for Supporting the Rapid Prototyping of Context-Aware Applications, 2001, Dey, Georgia Tec

The Context-Aware Mailing List

• Dynamic distribution list is used to deliver email messages to members of a research group who are currently in the building

• Addressing email-style communication to a group of people who are selected by their location.

• Context-aware mailing list built with the

Context Toolkit

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Architecture diagrams for the In/Out Board and

Context-Aware Mailing listApplications

3. MessagingMessaging : contextual reminder/messaging

• By knowing the situation of the receiver or addressee,

the right message can be delivered at the right time and in the right form,

be it a reminder message or an incoming e-mail

Hanging Messages – using Context-Enhanced messages for just-In-Time communication, 2001, Chang and Maes, MIT

What is a hanging message?

• Context-enhances message for just-in-time communication

• A message which is delivered to a recipient at a specific place and time

• Envision the message as “hanging” in a certain location, waiting for the recipient

• Messages are context enhanced for better filtering

Mobile wireless device agent : Located an on each user's device

• make use of existing context to filter incoming communications.

• A user should never receive any unsolicited or irrelevant message

Filtering mechanisms :

hierarchical categorization for messages

user profiling by rules

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4. Providing Awareness of callee

Providing awareness of callee or receiver

• One can determine if the individual is available to talk by presence awareness

• Presence awareness is similar to the idea of status in Instant Messenger systems

Context-aware communication with Live Contacts, 2004, G. Henriter Hofte

Live Contacts system (running on pocket PC phones, PC)

Presence information of listed contacts,

• current Messenger status (e.g., busy, online, away, on-the-phone, etc.)

• current calendar information (e.g., work and non-work times, appointments,…)

• last-known location information (e.g., at work, at home, on move, or unknown)

One can initiate contact (via telephone call, SMS, IM, or e-mail)

or ask to be reminded to make contact at a nominated future time.

Live Contact servers : A client–server architecture - querying for updates on contacts

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5. ScreeningScreening : establishing communication under appropriate conditions

• Filtering or redirecting calls based on the situation of the receiver combined with the previous application types

• Inform the caller of the callee’s situation , and takes action automatically on perceiving that the callee is unavailable

Ex) In a meeting, then the phone can be put in a certain mode, virtually filtering the call

Calls.calm : callee specifies the extent of a caller’s access to situation information and communication channels in a database of relationships

Uses Web phones to mediate communication with subscribers.

A person selects who to call, and he is greeted by the callees, contact page contextualized and customized for the caller; if the caller is unknown, (c) a generic page.

For trusted callers, Calls.Calm reveals status, messages, and a list of preferred communication channels.

The system supports negotiating a time to make a voice call by an exchange of short text messages

The aforementioned application types may be combined in a specific application

Ex) Route messages using context as well as filter appropriate messages

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Call Services Applying a Disciplined Approach to the Development of a Context-Aware

Communication Application, 2005, Ted McFadden, Australia

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Context Information : location , the status of the user, available communication mode (e.g., voice, text, or video), device battery power

Context Modeling Language (CML) :represent the context representation for context-communication application

ECA (Event, Condition, Action) modelthe precondition in this case is always true, and the action is to re-evaluate preferences for the call of concernProcess the ‗Locate‘ messages1. Context Manager is queried to discover

devices near the user2. devices are rated against the FinalEval

preference3. If any device gets an oblige score,

it is selected for use.4. The SIP address for the device selected at

step 3 is determined from the “has address”

Call Services

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Context fact model for the communication application

Application Types

Application types: addressing & context-aware commands

Ex) “when the 8 p.m. news is finished and if no one is watching, turn off the television next to the chair John is sitting in.”

addressing : to TV by the context

command : “turn off” performed in the right context

Context ensures that commands are delivered in the right way and at the right time to appliances.

Sensing/thinking/acting subsystems are studied previously.

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Command Interpreter Determine the attribute

Sensing Reasoning Action

Smart Space

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Smart space : it can intercept and understand user commands

Context-aware command processor : execute commands issued by a speaker

- interprets the user’s commands, translates it into an operation on a device,

- and invokes the operation on the device

Query sensors & devices whether a command has been successfully completed

Server : continuously listens for user commands and has access to devices

Devices have an API or a Web service-like interface for invoking the operations

UPnP Design by Example, 2003, Jeronimo, Intel

UPnP(Universal Plug & Play) for future devices.

Interface to devices to communicate with or make use of the device

Action invoking to a UPnP control point

Ex) 3 services for Super Toaster device

• Lifetime Statistics, Toaster Status, Toaster Control

http://www.jini.org/wiki/Category:Introduction_to_Jini

Jini : SUN

• Provides a Java-based object model of devices

• Discovery, Join, look-up, and client uses service.

Smart Space

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TV

door

Lamp

Smart Space

Utterance WOperation

Infra Structure : Determine the situation such as which device ?

Sensing/Thinking/Action

Sensors

Query

Command to target devices

Query

Context-Aware Sensor networks

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Context-Aware SensorsA survey on sensor network, 2002, Akyldiz, Georgia

Life Patterns: structure from wearable sensors, 2002, Brian Patrick Clarkson MIT

Sensor Networks

• Numerous applications : from kinder garden to traffic management

• Understanding regularity in everyday life behavior (wearable sensors MIT)

• Life patterns are the reoccurring events in daily behavior, such as those induced by the regular cycle of night and day, weekdays and weekends,

work and play, eating and sleeping

Researches : networking protocols, Hardware, Operating systems, Programming model

2 related topics for Sensors and Context-aware Computing

• Sensors are used to acquire context information

• Sensors themselves can be made to be aware of their own context

Context-Aware Sensors:

Sensor networks + Context-aware computing

• whose behavior can be changed in response to their current context,

• power-conserving actions depending on the situation the sensors are in.상황인식 2010 가을 12 주차 53

Context Information

Sensor

Aware

Acquire

Context-Aware Sensors: The Concept

WSN : wireless sensor network

a combination of low cost, low-power, multifunctional miniature sensor devices consisting of sensing, data processing, and communicating components, networked through wireless links between neighboring nodes

Large number of sensor nodes are deployed over an area

Mesh network : relay sensed information to base station

Energy constraints of sensors

for Sensing/Computing/Networking

Idea of Context-aware sensors

• If sensors know more about their own context, then they could adapt their behavior and function only when needed in the current circumstances

they becomes more prudent for spending energy

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Architecture

Framework

• Setting of groups of sensors – provide context & send/receive commands

• Several support services – provide communication between sensors and the system

• Components to provide the core functionalities for context discovery & use

the sensor nodes –

• Programming : nesC under TinyOS

• To interface with the sensors : Java 1.1 API is used for modules that provide data collection, analysis, and communication between the motes and the base station

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Architectural diagram

Architectural diagram showing the main components of the framework

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Frameworks

Sensor groups :

• Send sensor readings to communication server

• Receive sensor control commands from the “Context Trigger Engine” via communication server.

Communication server:

Acts as a mediator between the base station and the sensors

and provides a unified protocol of communication for applications

• Parse raw data packets from the sensors into a format recognizable by App.

• Parse control messages from the application to the sensors

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Frameworks

Context locator service: Interpret the current context from the raw sensor readings

• If-else condition rules – decide whether certain context has been acquired

• Form secondary context by conjunctions of different primary context information

Context mining service: context discovered autonomously in the system

• User programmed rules - Static context discovery and dependent on designed scenarios

• With this service,

• Context locator service would be sampling sensor data

• Context mining service would be discovering context

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TempSensor Context locator

serverTempSensor

IF temp sensor < threshold,Primary context is cold

IF groups of temp sensors < threshold,Secondary context is coldweatherContext

Lookup

Context name

Frameworks

Context trigger engine: determines the sensor operations triggered,

• using a combination of given context and sensor profiles

• Action macros : a command or a combination of actual commands sent to sensors

Context action data store: Relationship between context & its respective actions

• 1-to-1 mapping, mapping with interdefined relationship

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Context scheduler

Macro Decoder

Action Interpreter

Context Actions

Data store

Request

Action macroTime-to-trigger

Context, Sensor group

Sensor control message

Sensor command

Action operation

DB

Sensor profile

operationsSensor ID

Other context information (Ex: current time,) about the system can be used.

Put found action macro on the queue to be scheduled for triggering.The queue operates based on a time-to-trigger parameter

Decompose the macro into simpler instructions to be sent to the listeningapplication running at a base station

Context-Aware Security

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