Review 1 부분3


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Review 1 부분3

  1. 1. Context-Aware Communication for PeopleTelephone 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 MeetingContext-aware communication • Make the phone not ring except in an appropriate manner Evolution of VoIP • The Phone rings at the callee situations PRID : Rich Presence ID automatically derived from sensors: physical presence, movement electronic activity: calendars Provide watchers with better information about the what, where, how of presentities상황인식 2010 가을 11 주차 41
  2. 2. 1. RoutingRouting : 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 AltoUbiquitous 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 상황인식 2010 가을 11 주차 42
  3. 3. 2. AddressingAddressing : contextually appropriate people (mailing lists and shared spaces) • Entities can be addressed based on their context instead of their unique identifier or namesA Conceptual Framework and a Toolkit for Supporting the Rapid Prototyping of Context-Aware Applications, 2001, Dey, Georgia TecThe 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 Architecture diagrams for the In/Out Board and Context-Aware Mailing list Applications상황인식 2010 가을 11 주차 43
  4. 4. 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-mailHanging Messages – using Context-Enhanced messages for just-In-Time communication, 2001, Chang and Maes, MITWhat 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 filteringMobile wireless device agent : Located an on each users device • make use of existing context to filter incoming communications. • A user should never receive any unsolicited or irrelevant messageFiltering mechanisms :  hierarchical categorization for messages  user profiling by rules  multiple location-based operational modes for each user.상황인식 2010 가을 11 주차 44
  5. 5. 4. Providing Awareness of calleeProviding 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 systemsContext-aware communication with Live Contacts, 2004, G. Henriter HofteLive 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 상황인식 2010 가을 11 주차 45
  6. 6. 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 callCalls.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 messagesThe aforementioned application types may be combined in a specific application Ex) Route messages using context as well as filter appropriate messages 상황인식 2010 가을 11 주차 46
  7. 7. Call Services Applying a Disciplined Approach to the Development of a Context-Aware Communication Application, 2005, Ted McFadden, AustraliaContext Information : location , the status of the user, available communication mode (e.g., voice, text, or video), device battery powerContext Modeling Language (CML) : represent the context representation for context-communication applicationECA (Event, Condition, Action) modelthe precondition in this case is always true,and the action is to re-evaluate preferencesfor 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” 상황인식 2010 가을 11 주차 47
  8. 8. Call Services Context fact model for the communication application상황인식 2010 가을 11 주차 48
  9. 9. 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.Command Interpreter Determine the Sensing Reasoning Action attribute상황인식 2010 가을 11 주차 49
  10. 10. Smart SpaceSmart 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 operationsUPnP Design by Example, 2003, Jeronimo, IntelUPnP(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  Jini : SUN • Provides a Java-based object model of devices • Discovery, Join, look-up, and client uses service.상황인식 2010 가을 11 주차 50
  11. 11. Smart Space Smart Space Lamp Command to target devices door Query Utterance W TV Operation Query Sensors Infra Structure : Determine the situation such as which device ? Sensing/Thinking/Action상황인식 2010 가을 11 주차 51
  12. 12. Context-Aware Sensor networks 윤 용운 2010.11.18상황인식 2010 가을 52
  13. 13. Context-Aware SensorsA survey on sensor network, 2002, Akyldiz, GeorgiaLife Patterns: structure from wearable sensors, 2002, Brian Patrick Clarkson MITSensor 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 sleepingResearches : networking protocols, Hardware, Operating systems, Programming model2 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: Aware Context Sensor Information AcquireSensor networks + Context-aware computing • whose behavior can be changed in response to their current context, • power-conserving actions depending주차 the situation the sensors are in. 상황인식 2010 가을 12 on 53
  14. 14. Context-Aware Sensors: The ConceptWSN : 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/NetworkingIdea 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 상황인식 2010 가을 12 주차 54
  15. 15. ArchitectureFramework • 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 & usethe 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 station상황인식 2010 가을 12 주차 55
  16. 16. Architectural diagram Architectural diagram showing the main components of the framework상황인식 2010 가을 12 주차 56
  17. 17. FrameworksSensor 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 sensors상황인식 2010 가을 12 주차 57
  18. 18. FrameworksContext 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 Lookup IF temp sensor < threshold, Temp Sensor Context locator Primary context is cold Temp server Sensor IF groups of temp sensors < threshold, Context Secondary context is coldweatherContext nameContext 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 상황인식 2010 가을 12 주차 58
  19. 19. FrameworksContext 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, Sensor group Other context information (Ex: current Request time,) about the system can be used. Context Context scheduler Put found action macro on the queue Actions Action macro to be scheduled for triggering. Data store Time-to-trigger The queue operates based on a time- to-trigger parameter Macro Decoder Decompose the macro into simpler instructions to be sent to the listening application running at a base station operations Action Action Interpreter Sensor ID operation Sensor DB profile Sensor control message Sensor commandContext action data store: Relationship between context & its respective actions • 1-to-1 mapping, mapping with interdefined relationship 상황인식 2010 가을 12 주차 59
  20. 20. Context-Aware Security 윤 용운 2010.11.25상황인식 2010 가을 60