Lecture 23: The Case for HomeOS

Lecture 23: The Case for HomeOS

Xiaowei Yang

Today’s Plan

• HomeOS–Why & How

• Final Review–We’ve learned a lot!

• Course Evaluation

3

Smart homes

• Capability to automate and control multiple, disparate systems within the home [ABI Research]

• Today, only the super rich and super geeks have it

HomeNets | ratul | 2010

4

Why don’t you have it?

• You have the basic ingredients• But composition is difficult

HomeNets | ratul | 2010

A quick example

Unlock?

Yes No

Why is device composition in the home hard?

• Users

• Developers

• Vendors

Home users are not administrators

• Management Nightmare

Why developers are not helping: heterogeneity

Application

HardwareThe actual devices in the house

Application

TopologyHandle WiFi vs. 3G vs. Eth, Subnets

HardwareThe actual devices in the house

Application

DeviceHandle different brands/models

TopologyHandle WiFi vs. 3G vs. Eth, Subnets

HardwareThe actual devices in the house

Application

CoordinationWhen apps disagree, who wins?

DeviceHandle different brands/models

TopologyHandle WiFi vs. 3G vs. Eth, Subnets

HardwareThe actual devices in the house

ApplicationUser Preference

What is automated? When? How?

CoordinationWhen apps disagree, who wins?

DeviceHandle different brands/models

TopologyHandle WiFi vs. 3G vs. Eth, Subnets

HardwareThe actual devices in the house

Application LogicUser Preference

What is automated? When? How?

CoordinationWhen apps disagree, who wins?

DeviceHandle different brands/models

TopologyHandle WiFi vs. 3G vs. Eth, Subnets

HardwareThe actual devices in the house

Vendors prefer vertical integration

• Vertically integrate hardware and software• Seldom make use of other vendors’ devices• No single vendor comes close to providing all

the devices a home needs

ClimateControl Remote

Lock

Camera-Based Entry

Video Recording

Interoperability is not sufficient

• Many standards exist for interoperability– Media: DLNA (Digital Living Network Alliance), AirTunes, etc.– Devices: UPnP, SpeakEasy, mDNS, etc.– Home Auto: Zwave ZigBee, X10, etc.

• Handles device heterogeneity, not topology, user preferences, and coordination heterogeneity

Monolithic systems are inextensible

• Security: ADT, Brinks, etc.• Academic: EasyLiving, House_n, etc.• Commercial: Control4, Elk M1, Leviton, etc.

Home Media

Security

An alternative approach: A home-wide operating system

Operating System

Video Rec.

Remote Unlock Climate

HomeStore

Goals of HomeOS

• Simplify application development

• Enable innovation and device differentiation

• Simplify user management

Core Features of HomeOS

• Driver and application modules• A “port” abstraction for exposing functionality

and communication• Access control for users and modules

Simplify development

…

…App A App B

Application LogicUser Preference

What is automated? When? How?

CoordinationWhen apps disagree, who wins?

DeviceHandle different brands/models

TopologyHandle WiFi vs. 3G vs. Eth, Subnets

HardwareThe actual devices in the house

Application LogicUser Preference

What is automated? When? How?

CoordinationWhen apps disagree, who wins?

DeviceHandle different brands/models

TopologyHandle WiFi vs. 3G vs. Eth, Subnets

HardwareThe actual devices in the house

Application LogicUser Preference

What is automated? When? How?

CoordinationWhen apps disagree, who wins?

DeviceHandle different brands/models

TopologyLogically centralize devices

HardwareThe actual devices in the house

Application LogicUser Preference

What is automated? When? How?

CoordinationWhen apps disagree, who wins?

DeviceStandardize at functional layer

TopologyLogically centralize devices

HardwareThe actual devices in the house

Application LogicUser Preference

What is automated? When? How?

CoordinationAccess control mediates conflicts

DeviceStandardize at functional layer

TopologyLogically centralize devices

HardwareThe actual devices in the house

Application LogicUser Preference

Users’ manage access control rules

CoordinationAccess control mediates conflicts

DeviceStandardize at functional layer

TopologyLogically centralize devices

HardwareThe actual devices in the house

Simplify development

…

…App A App B

Driver Driver…Port Port

…

Access ControlMgmt

UI

Modules

• Driver and application modules are isolated– A poorly written module can’t impact HomeOS or

other modules

• Application modules belong to application domain

• Communication cross domains is through pre-defined entry points

A port example

• A port is functionally described in terms of roles and controls– Roles: express a functionality– Controls: typed points of sensing and actuation within a

port

• < roles=“lightswitch”, “dimmerswitch” > , < controls=(“on-off”, binary, readable, writable), (“intensity”, range:1-100, readable, writable) > .

Roles in HomeOS

• Roles are functional descriptions of ports– lightswitch, television, display, speakers, etc.– App developers program against roles

• Enable vendors to innovate/differentiate– Anyone can create a new role• e.g., SonyBraviaTV vs. television• Allows new functionality to be rapidly exposed

– Commodity vendors can still participate

Simplify user management

• Conducted a field study–Modern homes with automation & other tech– 14 homes, 31 people

• Users’ needs for access control– Applications as security principals– Time in access control decisions– Confidence in their configuration

Management primitives• Datalog access control rules

– (port, group, module, time-start, time-end, day, priority, access-mode)– Reliable reverse perspectives help users confidently configure access

control

• User accounts– Can be restricted by time (guests)

• Application manifests– Specify role requirements for compatibility testing– Simplifies rule setup (only when roles match)

Implementation status

• Built on the .NET CLR• ~15,000 lines of C#

– ~2,500 kernel• 11 Applications

– Average ~300 lines/app

• Music Follows the Lights– Play, pause & transfer music

where lights are on/off

• Two-factor Authentication– Based on spoken password and

face recognition

Open questions/Ongoing work

• Additional evaluation– Is it easy to write apps and drivers?– Is it easy to manage?– Does it scale to large homes?

• Deploy & support application development

• Explore business/economic issues

Conclusion

• A home-wide OS can make home technology manageable and programmable

• HomeOS balances stakeholder desires– Developers: abstracts four sources of heterogeneity– Vendors: enables innovation and differentiation– Users: provides mgmt. primitives match mental models

http://research.microsoft.com/homeos

Discussion

• Do homes need an OS?

• Is HomeOS the right solution?

• Why would vendors comply?

Course Summary

• A broad range of topics– Cloud computing and its challenges– Cloud inner working– Datacenter networking– Social networks– Privacy• Web, Wireless, Mobile devices

– Home Networking

Cloud Computing: Opportunities

• Opportunities– Elastic computing: on-demand scaling– Pay-as-you-go• No upfront investment cost

– New applications• Mobile & Cloud• Energy saving• Disaster recovery• Group collaboration

Cloud Computing: Challenges

• Security– Placement– Co-location– Inference

• Performance• Sharing impacts computation, network

Cloud Inner Workings

• MapReduce– A powerful framework for parallel computation– Map()

• Process a key/value pair to generate intermediate key/value pairs• map (in_key, in_value) -> (out_key, intermediate_value) list

– Reduce()• Merge all intermediate values associated with the same key• reduce (out_key, intermediate_value list) -> out_value list

• MapReduce online for interactive applications• Reining outliers

Example: word counting

• Map()– Input <filename, file text>– Parses file and emits <word, count> pairs• eg. <”hello”, 1>

• Reduce()– Sums all values for the same key and emits <word,

TotalCount>• eg. <”hello”, (1 1 1 1)> => <”hello”, 4>

Datacenter Networking

• FatTree– Multi-rooted trees to provide abundant bisection bandwidth

• Adaptive routing– Valiant routing: picking a random redirection point works

• Datacenter congestion control– InCast: synchronized replies lead to congestion– DCTCP

• Reduce cwnd proportionally to congestion• Small queue size in routers

Social network storage

• Haystack–Write once– Read many– Using a needle to hold many files– Cache metadata in memory for high access speed

Privacy

• Social networks– Personal identifiable information leaks to

unauthorized third parties• Cookies, referrer header, Request-URI

– User browsing behavior is linkable

• Online advertising– Behavior targeting in social networks

• Ads exclusively sent to users in certain groups– Not obvious for search and web ads

• Mostly keyword based

• Wireless–Mobility pattern linkable– Anything over http spoofable– SlyFi

• TaintDroid– Private information leaks to unauthorized 3rd party

The End• It’s really the beginning

• Take the ideas

• Apply the skills– Critical and creative thinking

• Turn your course project into a research paper

• I hope you enjoyed it as much as I do