Enhancement of IPTV using a Wireless Sensor Network

Sandeep Kakumanu,Sriram Lakshmanan, and Raghupathy Sivakumar

GNAN Research Group

Georgia Institute of Technology

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IPTV-Introduction Packet based transmission of television streams

using the Internet Protocol Envisaged Advantages (over conventional TV):

On demand channel access permits bandwidth to be utilized entirely for active channels

High levels of user interaction Viewable channels not limited by either geographical

location Number of channels not limited by access link

bandwidth Video sources not restricted to high end content

providers enabling larger variety and diversity of channels

Allows integration with the Internet

Private/Public wired network

IPTV Architecture Satellite content

Off air contentLocal content

Encoders

VOD server

Ad server

Video servers

Internet

Local Headend

IPTV Subscribers

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IPTV Architectures Classification based on connection nature

Unicast Multicast

Classification based on communication infrastructure Model 1: Public internet with no provisioning Model 2: Public internet with service provisioning Model 3: Private IP Network

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Challenges Loss rate

Bandwidth constraints lead to high and varying loss rates

The acceptable loss rate for television < 1% * Channel switching latency

Delays from server to client (due to potentially large geographical separation)

On-demand nature also incurs stream stop, setup delays

Acceptable channel switching latency < 1s * Management of large number of subscribers

*[Source:Gartner Research Report , 2005]

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WSN Enhancement 1: Quality Principle

“What you see is what you fetch” In cases where there is no active user but the

television is on, such streams can be communicated at low priority, low data rate or even paused.

Realization The Wireless Sensor network senses user

presence/absence. A combination of light sensors mounted on the chair

and accelerometers to detect cushion deformation is used to determine user presence/absence.

Multimedia stream control is done based on sensor values.

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WSN Enhancement 2:Pre-fetching

Principle “Fetch possible next channel(s) just before the user

switches” Pre-fetching is a powerful technique that can be used

to reduce the user perceived channel switching latency.

Realization The WSN at the user premises can be used to provide

real time feedback about when to pre-fetch and when not based on

The motion of the remote control Accelerometers used to detect motion of remote

control.

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WSN Enhancement 3:Targeted Advertising

Principle One of the goals of IPTV is to provide user-specific

and relevant content Targeted Advertising (user relevant advertisements) is

a unique possibility of IPTV Realization

A WSN enables collecting information about the user on which the targeted advertising decisions can be based

The ambient conditions of the room or the environment around can be used

Use temperature, humidity, pressure, light sensors

VLC Server

Network Nightmare

WLAN router

Sink

Viewer

LCD MonitorLCD Monitor

STB/LaptopViewer

192.168.1.11

192.168.1.101

192.168.1.1

192.168.1.12 192.168.1.14

192.168.1.100

STB/Laptop

TESTBED SETUP

SensorsSensors

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Future Work Optimize the code at both the IPTV software and

the Sensor Network software for minimum possible reaction times

Modify the medium access scheme of the sensor network for reduced delay

Explore use of WSN for IPTV over wireless. Design algorithms for cases where each house

has several televisions. Design algorithms for unicast and multicast load

balancing using sensed data