1. Is there a meeting in this room right now?
Context Fabric
Jason I. Hong
James A. Landay
or, Infrastructure Support for Context-Aware Applications
What is Context-Aware Computing?
Context Specification Language
The goal of context-aware computing is to provide tighter ties between the physical and social worlds we live in and the virtual world in which computers operate. Context-aware computing does this by expanding the richness and diversity of inputs that computers can sense.
Provide a flexible and high-level interface for declaratively stating context needs.
Location
"What are the five nearest movie theaters?"
Activity
"Turn off my cell phone when I'm in
a meeting or in a restaurant."
Who is <this person / that person>?
Identity +
Proximity
"Remind me to talk to Chris about Iron
Chef next time I see him."
Is <person> near <person>?
Is <person> currently <busy / available>?
Multiple
"Where on earth was that picture taken?"
"Is this a photo from Phoebe's wedding?"
"Who is that sitting next to Ralph?"
Is <place> currently <busy / available>?
Where <is / was / will> <person>?
What are the <N> nearest <people> right now?
Problem - Still Very Hard to Build Context-Aware Systems
However, there are still high barriers to entry. App developers must deal with distributed systems issues, sensors, recognition algorithms, and so on. An infrastructure provides an always-on “context dialtone” that all apps can rely on being there.
Network
Services
Privacy?
Automatic Path Creation
Agents
Coordinate available sensor input and services together to address queries made with the context specification language.
What are the nearby movie theaters?
Diverse
Platforms
Diverse
Context
Sensor and
Context
Fusion
Sensor Input
Data
Ambiguity
GPS
ZIP
ZIP
Theaters
GPS
Sensor Input
Context Output
Nearby Movie
Theaters
Cell
ZIP
ZIP
Theaters
Cell Location
Context
Streams,
Events,
Queries
Automatic
Path
Creation
Probabilistic
Framework
Recognition
Algorithms
Sensor Input
Cell
GPS
GPS
ZIP
ZIP
Theaters
Problem
Areas
Cell Location
Is there a meeting in this room right now?
Precision
Granularity
Accuracy
Metadata
wav
single speaker?
Sensor Input
Diverse
Sensors
Unreliable
Sensors au
wav
Proposed
Solution
Sound
Context Output
Probability of
Meeting
wav
audible?
fusion
meeting?
mpeg
motion?
Video