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Ubiquitous Computing in Home Networks

Henning Schulzrinne, Columbia University Stefan Berger, IBM ResearchIEEE Communication Magazine 2

003

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Everyone can communicate to

Everything Everywhere

E-E-E

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Ubiquitous Computing

Multimedia Device integration Event-based Location-aware Privacy-conscious Invisible to user

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System Architecture The context around the user

Location information Multimedia resource

The intelligent end system the user hold Retrieves the location and resource

information Transfers the information to SIP server Control the resources

5Ubiquitous Computing System Architecture

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System Architecture

The core of the intelligent end system Location sensing Resource discovery and management Call control

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Location Sensing Self determines

GPS Useless indoor

The field strength of wireless access point Need two APs

Location beacon Bluetooth IR/RF DHCP Server

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Location-Based Service

Triggers automated behavior Selects watchers Governs communication behavior

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Location-Based Service

Two control mode User centric

Selects the types of devices for witch the user has defined preference

Device centric Device subscribe to user presence

and store preference

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Resource Discovery and Control

Back-to-back user agent A logical entity that receives a

request and processes as a user agent server(UAS)

And acts a user agent server(UAC) to determine how to answer the request and generates requests

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Call Control

Event-triggered actions Received from the location sensing Service discovery Inbound or outbound call

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Control Messaging Using SIP

Text-based message XML

HTTP Encode as URI parameter

SOAP(Simple Object Access Protocol) More powerful More complex

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Access Control

Explicitly registered to local server RADIUS or DIAMETER (AAA) Location information

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Prototype Implementation

The CINEMA system Columbia InterNet Extensible Multimedia A

rchitecture SIP proxy, redirect, registration server(SIP

D) SIP voice mail SIP conference service Service logic execution environment(SLEE)

15SIP-based ubiquitous computing in a hotel

Visited domain

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Conclusion

Presented a global-scale ubiquitous computing architecture

Based on standard SIP and SLP Implementation CINEMA system