1. The Gaia System

2. 6.893 Spring 2004: Gaia Larry Rudolph Not Invented Here Lots of Pervasive Computing Projects Carnegie Mellon Univ. U. Washington Georgia Tech UC Berkeley Univ. Illinois Urbana Champaign Gaia England & Scandinavia & ??

3. 6.893 Spring 2004: Gaia Larry Rudolph Similarities Pervasive computing can be characterized as: Extensive management for components (services, devices) Components are autonomous Some application programming support: Java or Python Rules or scripts Still very primitive (in my opinion)

4. 6.893 Spring 2004: Gaia Larry Rudolph Middleware Gaia Architecture Gaia Kernel Event Manager Context Service Context File System Component Repository Presence Service Space Repository Resource Management Service Application Framework Configuration Management Service QoS Instantiation Service QoS Translation Service QoS Adaptation Service Applications Component Management Core

5. 6.893 Spring 2004: Gaia Larry Rudolph Component Management Core Provides functionality to manipulate components in Gaia: Creation Destruction Uploading Contains three basic abstractions: Components Component Containers Nodes

6. 6.893 Spring 2004: Gaia Larry Rudolph Component Management Core Gaia Components Gaia Component Container Gaia Node Examples Gaia Node Active Space Gaia Component Container Gaia Node

7. 6.893 Spring 2004: Gaia Larry Rudolph Gaia Kernel Services Event Manager Context Service Context File System Component Repository Presence Service Space Repository

8. 6.893 Spring 2004: Gaia Larry Rudolph Event Manager Loosely coupled communication based on channels. Supports push, pull, and hybrid mechanisms. Supports creation of named event channels and distribution of load.

9. 6.893 Spring 2004: Gaia Larry Rudolph Event Manager Event Channel Factory 1... Event Channel Factory n CreateChannelType DeleteChannelType CreateEventChannel GetEventChannel DeleteEventChannel ListChannelTypes ListEventChannels Consumers Suppliers Event Channels

10. 6.893 Spring 2004: Gaia Larry Rudolph Context-Aware Applications Situational information, or context, increases richness of communication in human-computer interaction. Makes it possible to produce more useful computational services. Example contexts: location, time, weather, stock prices, moods, user activity, …

11. 6.893 Spring 2004: Gaia Larry Rudolph Context Service Provides a taxonomy and uniform representation of context types. Provides an infrastructure to promote design, implementation, and evolution of context-aware applications.

12. 6.893 Spring 2004: Gaia Larry Rudolph Context File System Data Organization: Context affects data organization. Data important in current context is easily accessible. Can attach context to files and directories. Context: situation, location, space, group, time. Data Transformation: Applications open data as desired type – dynamically typed file system. System converts data to desired type.

13. 6.893 Spring 2004: Gaia Larry Rudolph Data Organization space = office location = RM2401 time = 11/28/01

14. 6.893 Spring 2004: Gaia Larry Rudolph Data Transformation MPEG Container MPEG Pixel2Bitmap Converter Text2Audio Converter GIF2Pixel Converter Pixel2Bitmap Converter BitmapContainer AudioContainer Mail Container PowerPoint Container MailPowerPoint BitmapContainer MP3 Container MP3 PCM2GSM Converter GSMContainer

15. 6.893 Spring 2004: Gaia Larry Rudolph Component Repository Provides persistent storage of components. Allows addition, removal, and browsing of components. Used by Component Management Core to dynamically retrieve components.

16. 6.893 Spring 2004: Gaia Larry Rudolph Presence Service Detects the presence of digital and physical entities. Generates events based on entity presence: ENTER LEAVE Defines a group of event channels to disseminate presence information. Maintains soft-state of all digital entities through a leasing mechanism.

17. 6.893 Spring 2004: Gaia Larry Rudolph Presence Service Digital Entity Presence Physical Entity Presence Person Tracker Applicatio n Servic e Device Perso n Event Manager Channels Device Presence Channel Person Presence Channel Service Presence Channel Application Presence Channel Enter Leave Events

18. 6.893 Spring 2004: Gaia Larry Rudolph Space Repository Centralized repository containing information about active entities. Interacts with Presence Service to keep information up to date. All entities described by a set of properties (e.g., entity type, name, location, owner). Exports a query interface based on properties.

19. 6.893 Spring 2004: Gaia Larry Rudolph Space Repository Detection Mechanism Database Presence Channels Component Query Interface Component

20. 6.893 Spring 2004: Gaia Larry Rudolph Application Framework Active Spaces render traditional applications obsolete. Applications for Active Spaces are: Distributed Adaptable Mobile Multi-Machine User Interface

21. 6.893 Spring 2004: Gaia Larry Rudolph Traditional Application Mapping Display Controller Application Logic

22. 6.893 Spring 2004: Gaia Larry Rudolph Active Space Application Mapping Controllers Displays Application Logic

23. 6.893 Spring 2004: Gaia Larry Rudolph Model – Presentation – Controller – Coordinator Application Framework Coordinator Application Functional Level Application Meta-Level MPCC Application Model Slide Show Data ControllersPresentations

24. 6.893 Spring 2004: Gaia Larry Rudolph Model – encapsulates the application logic. Presentation – presents the data of the model (audio, video, changes in the physical environment). Controller – modifies the state of the model. Coordinator – manages the application architecture (application meta-level). MPCC Application Framework

25. 6.893 Spring 2004: Gaia Larry Rudolph

28. Application Generic Description

29. 6.893 Spring 2004: Gaia Larry Rudolph Application Concrete Descp.

30. 6.893 Spring 2004: Gaia Larry Rudolph

31. Applications Mobile Video Context Data Browser Presentation Viewer

32. 6.893 Spring 2004: Gaia Larry Rudolph Mobile Video Media Server Component Database Location ALocation B Move! User Profile Server Media Gateway

33. 6.893 Spring 2004: Gaia Larry Rudolph Context Data Browser File Mode Context Mode

34. 6.893 Spring 2004: Gaia Larry Rudolph Presentation Viewer

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37. The Context Model Enables creation of complex, first-order expressions involving context Makes it possible to write rules, prove theorems, evaluate queries

38. 6.893 Spring 2004: Gaia Larry Rudolph Basic Structure Four parts: context-type Subject: Person, place, or thing Relater: something that related subject to object Object: is a value associated with subject

39. 6.893 Spring 2004: Gaia Larry Rudolph Some examples Context(Location, Chris, Entering, G868) Context(Temperature, G868, Is, 98F) Context(Stock Quote, IBM, >, $60 ) Context(Printer Status, Pulp, Is, Empty) Context(Time, New York, Is 12:00 01/01/04)

40. 6.893 Spring 2004: Gaia Larry Rudolph Operations on Contexts Boolean, Existential, Quantification Context(lighting, G868,Is,Off) OR Context(lighting, G828,IS, Dim)

41. 6.893 Spring 2004: Gaia Larry Rudolph Context Chat