Chapter 5: Pervasive Systems

Question 1

What is the motivation behind pervasive systems?

Answer 1

• Context-awareness can help to build smart apps
• Embedded devices contribute to natural use of computing capabilities
• Pervasive systems is more than a single device its a set of devices that cooperate with each other

Question 2

What are the characteristics of a pervasive system?

Answer 2

• spatially limited area
• set of devices
• functionality through pervasive applications

Major challenge: Coordination of applications and their interfaces via context model

Question 3

What are the characteristics of a pervasive application?

Answer 3

• Distributed applications
• make use of currently available resources (of devices)
• Context interactive
  
  • context-aware (app depends on certain context)
  • context-altering (app influences a certain context)

Question 4

What kind of system architecture models exist for pervasive systems?

Answer 4

• Smart Environments (Gaia)

- Smart Peer Groups (3PC)

Question 5

What is the difference between a Smart Environment and Smart Peer Group?

Answer 5

Smar Environment (Centralized):

• Needs a fixed infrastructure (controls everything, provides services)
• mobile devices communicate via pervasive system controller

Smart Peer Group (Decentrelized):

• Mobile devices, no infrastructure (Self-organization)
• Connection between each mobile device
• Devices discover services in smart peer group

Question 6

What is the Gaia concept?

Answer 6

• They provide a new abstraction via a Meta-Operating System (Middle-ware)
• Pervasive applications are executed on top of the different platforms (on the meta-operating system)
• Different platforms are: Wearables, Smartphone, Pc,..)

Question 7

How does Gaia leverage active spaces?

Answer 7

• Active spaces combines physical space (devices and network) and technical space (context, SW infrastructure)
• Pervasive applications can use the resources of the active space for their computations

Question 8

How does the Gaia Architecture look like?

Answer 8

• Active Space Applications
• Application Framework (abstraction to develop active space applications)
• Core of the architecture is the Gaia Kernel (handles the communication between all resources in the active space)

Question 9

Explain the 3PC (Peer to Peer Pervasive Computing) System.

Answer 9

• It is a software stack with three layers
• COMITY: Coordinate apps in physical environment
• PCOM: Adapt single application (via interfaces to make them conform with other applications)
• BASE: establish smart peer group (Middleware Platform: to discover other devices, offer adaptive communication)

Question 10

What are three keywords that describe Ubiquitous computing?

Answer 10

• Helpful
• Invisible
• Unconscious

Question 11

What pervasive system do we have right now?

Answer 11

• Internet of Things (Embedded System)

But IoT != Pervasive System
- Technically the same but:

• Pervasive computing: Centered to humans
• IoT: Is not centered to humans

Question 12

What are the current challenges of pervasive systems?

Answer 12

• Energy Efficiency
• Interoperability
• Human Computer Interaction
• Business Models
• Security & Privacy

Question 13

What is the challenge of energy efficiency?

Answer 13

• Battery life of mobile devices is a big concern,
• Growing number of sensor / asynchronous networking

Two approaches:

• Power Management
• Power Harvesting (like solar panels)

Question 14

What is the challenge of interoperability?

Answer 14

Pervasive computing needs a middleware to support interaction of different devices in an open setting

Question 15

What is the challenge of Human Computer Interaction?

Answer 15

• Measure user distraction and stress
• Infer intention (proactive)
• Put user at the center
• Ethical issues (autonomy and self-determination, responsibility)

Question 16

What are the current challenges of Business Models?

Answer 16

• How to sustain pervasive computing commercial products ?
• Problem: Consume human-attention
• Smart spaces are expensive ( A lot of stuff is already working like time to leave with google maps. But Smart environment throughout the world is far away)

Question 17

What are the current challenges of Security & Privacy?

Answer 17

Privacy:

• Increasing awareness
• Improve I/O for privacy info
• Involvement of different entities (User, Developers, Governments, app stores, …)

Security:

• unobtrusive, adaptive
• Cope with energy, hyper-connection, diversity

Question 18

Why does no global system exist today?

Answer 18

Because of the interoperability challenge

Question 19

What does context interference in the domain of pervasive computing mean?

Answer 19

• Context interference refers to multiple applications changing the same context variable in the same domain (e.g., in the same room).
• E.g., two applications in a smart house, one that needs to dime the lights, and another that requires bright conditions to operate.