Challenge 1: The "Accidentally" Smart Home
- infrastructure/standard for deploying ubicomp technology does not exist
- smart technologies being deployed piece-by-piece
- old fashioned homes will suddenly become smart (critical mass point)
- increasing number of ubicomp technologies in the home will make the home environment more complex and unpredictable
- example: my neighbor's stereo has started using my wireless speakers. How do I "debug" my speakers
- example: 802.11 failures, falling onto the wrong network. Technology designs may fail.
- question 1: How do we make the system intelligible? (e.g. is the device recording)
- question 2: How can I tell what is interacting?
- question 3: What are the boundaries of my home?
- question 4: What are the possible configurations of my devices?
- question 5: What are the possible configurations of my home?
- question 6: Where is the UI? Where is the locus of interaction?
- question 7: How do I control the devices and the entire system?

Challenge 2: Impromptu Interoperability: interacting without advanced planning or implementation
- as the number and types of devices increases, it will be impossible to plan ahead for future devices
- difficult to have a priori agreement on syntax and semantics
- need new models of connectivity (Stanford event heap, CoolTown, Speakeasy)
- have to prevent isolated islands of functionality

Challenge 3: No Systems adminstrator
- we don't expect users to administer plumbing and wiring, we can't expect them to administer ubicomp
- appliance model: single function devices that experts setup/repair
- challenge for appliance model: how can these devices offer rich interactions with other devices without losing their simplicity?
- utility model: push function into network (e.g. telephone is fairly simple, telephone network is not)
- challenge for utility model: how do we design the network to protect against malicious attacks?

Challenge 4: Designing for Domestic Use
- Smart technologies will disrupt the home
- study of telephone and electricity adoption important for ubicomp adoption
- telephone vendors did not foresee social role for telephones
- Palen et al: consumers tend to purchase mobile phones for emergency purposes, but then shift to social use
- Hughes TV study: occupants use TV to indicate that they control a particular room. Disputes settled by purchasing another TV or making the TV more mobile.
- Grinter SMS/IM study: teenagers use text messages to arrange times for phone conversations or IM chats on computer. "Quiet" technologies avoids disturbing other occupants routines.

Challange 5: Social Implications of Aware Home Technologies
- labor saving: some technologies designed to save labor, can increase and/or shift labor responsibilities by changing behaviors. Washing machine increased cleanliness standards and shifted labor to mothers.
- good parenting: technologies such at TV (V-Chip) and mobile phone can change ideas on parenting. Some parents use mobile phones to teach budgeting skills and increase child's independence.

Challenge 6: Reliability
- different standards of reliability between desktop applications and domestic technologies
- smart technologies should ideally be administration free

Challenge 7 Inference in the Presence of Ambiguity
- much of ubicomp research holds that context-awareness is crucial to the smart home
- how smart does the smart home have to actually be
- what is the cost of incorrect inferences?
- are the sensors just sensing sensors?
- trying to apply digital decisions to an analog world
- user must be able to predict and understand behaviors of their technology:
   - system's expected behavior given a particular condition is known
   - system's facilities for detecting conditions is known
   - provisions for overriding system's decisions
- ambiguity should not be hidden from the user