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Buddy Internet ExchangeLYU0701

Supervisor:Professor Michael R. Lyu

Prepared By:Kwong Kwok Wai - 06545093

Chan Kwan Ho - 06837554

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Review of first term

• Focus on thetransport-layer :Application independent

• Network topology discovery could have further benefits to P2P applications

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Motivation

• Hong Kong is in the progress of switching to High Definition TV Broadcast

• Current coverage is not complete• Most recorders could not record two channels

simultaneously• High bandwidth requirement to transfer over

the Internet

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Objective

• Build an easy-to-use TV scheduler• Share the TV contents to those who are

eligible to watch but not able to receive HDTV signals.

• Design a high-speed transfer protocol to optimize the total waiting time and the maximum waiting time

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Set-Top Box

• A device to decode digital TV signal.• Equipped with network capabilities.• Could record TV programs into a hard disk• Not programmable by 3rd party, so we will

simulate it using PC.

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Client Application

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Network Architecture

• Client / Server Model• Fully Decentralized Model• Hybrid Decentralized Model

– Efficient peer discovery– Bottleneck at peers only– Minor drawbacks

Peer Address

Peer Address

Peer Address

Peer Address

Data

Data

Data

Data

Data

Data

Peer A

Peer B

Peer C

Peer D

The network formation of a hybrid decentralized model

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Client Application

• Probe network connection speed for path determination

• Probe network port connectivity

1

Start

Load config

2

Probe network speed

4

if communicationport is open

3If communicationport is not open

End

Do settings

5

Open receiver in threadListening incoming connections

Failed to openreceiver

6

User click Create,select date and time

7Retrieve EPG from server

User selectprogram to record

8

User click Exit

Program timestarts

10

9

If recordingdevice is free,

Record the program

If recordingdevice is not free,

Receive from peers

Open sender in threadSend available data to other peers

Open sender in threadSend available data

to other peers

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Client Application

• Easy-to-use GUI for HDTV recording schedule

• Provides EPG for the coming week in form of XML

1

Start

Load config

2

Probe network speed

4

if communicationport is open

3If communicationport is not open

End

Do settings

5

Open receiver in threadListening incoming connections

Failed to openreceiver

6

User click Create,select date and time

7Retrieve EPG from server

User selectprogram to record

8

User click Exit

Program timestarts

10

9

If recordingdevice is free,

Record the program

If recordingdevice is not free,

Receive from peers

Open sender in threadSend available data to other peers

Open sender in threadSend available data

to other peers

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Client Application

• Records the HDTV program if hardware is available(not implemented)

• Forms a P2P network as instructed by server.

• Transfers HDTV contents

1

Start

Load config

2

Probe network speed

4

if communicationport is open

3If communicationport is not open

End

Do settings

5

Open receiver in threadListening incoming connections

Failed to openreceiver

6

User click Create,select date and time

7Retrieve EPG from server

User selectprogram to record

8

User click Exit

Program timestarts

10

9

If recordingdevice is free,

Record the program

If recordingdevice is not free,

Receive from peers

Open sender in threadSend available data to other peers

Open sender in threadSend available data

to other peers

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BIX sharing networkformation algorithm

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Algorithm design

• Goal– Smallest total waiting time (Main Idea)– Smallest maximum waiting time

• Cannot obtain both when huge number of ADSL users.

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Algorithm design

• Sorting peers– 1st type causes of bottleneck– 3rd type is not efficient in sharing– Priority of 2nd type > 3rd type > 1st type

0

50

100

150

200

250

300

1st Type 2nd Type 3rd Type

Upload Speed

Download Speed

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Algorithm design

• Sorting peers

Variances = with pi = 1, Xi = priority, mean = 0

priority = where x = priority

priority = priority * (user[uplink])1/2

25.1*:75.0*

?)0]))[][((

privorityprivorityprioritypriority

downlinkuseruplinkuserpriority

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Algorithm design

• Peers selection– Inter Peers Network Status Matrix (IPNSM)

]))[],[min(

(lim],[

,

downLinktoPeeruploadLinkfromPeer

sourceflowtoPeerformPeermatrix

toPeerpeersformPeerpeers

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Algorithm design

• Peers selection– In order of sorted list– Find the highest output node using IPNSM– Update IPNSM

]),[,min(

],[

ierselectedPematrixlectedPeeroutputToSe

ierselectedPematrixi

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Algorithm design

• Utilize non optimal link– Travel starts from leaf node– Connect to non optimal node in higher level

])[][&0][(

...

downloadthisdownlinktestNodeuplinktestNodeif

testNodeleafparentparentthisSelectNode

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Algorithm design

• Inter ISP policy – Rules applied on non-reserved port– Upload bandwidth limit on fan out number

• HKBN– Fan-out = 1, Output = MAX– Fan-out = 2, Output = MAX/2– Fan-out >= 3, Output = MAX/4

• -HGC– Fan-out = 1, Output = MAX– Fan-out >= 2, Output = 310kb/s

– Solution• Limit the number of connection to different ISP peer to 1

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Test Result

• Compare with Bit Torrent (BT)• Each test is done for 5 times• Equipment:

– 6PC– 2HKBN, 2HGC, 2PCCW

BB25

BB50

HGC 25M

HGC 10M

PCCW 6m

PCCW 18M

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Test Result

• Case 1: Sharing 100MB video file.• Source: HKBN BB25

• Total waiting time of BIX: 9m 45s• Total waiting time of BT: 17m 54s• Maximum waiting time of BIX: 3m 52s• Maximum waiting time of BT: 6m 14s

0

5

10

BIX

BT

BIX 0.92 0.92 2.03 2.03 3.87

BT 1.98 2.09 2.63 4.15 6.23

HKBN BB50 HGC 25M HGC 10M PCCW 18M PCCW 6M

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Test Result

• Case 4: Sharing 2GB video file.• Source: HKBN BB25

• Total waiting time of BIX: 3h 14m 46s• Total waiting time of BT: 4h 25m 2s• Maximum waiting time of BIX: 1hr 16m 8s• Maximum waiting time of BT: 1h 25m 56s

0

50

100

150

BIX

BT

BIX 18.23 18.4 40.73 41.27 76.13

BT 30.63 32.13 41.73 64.6 95.93

HKBN BB50 HGC 25M HGC 10M PCCW 18M PCCW 6M

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Test Result

Overall result

100MB file 600MB file

Maximum waiting time

Total waiting time Maximum waiting time

Total waiting time

BIX 3m 52s 9m 45s 23m 12s 58m 26s

BitTorrent (BT) 6m 14s 17m 54s 28m 45s 1h 18m 55s

Difference in % 61.1% 75.03% 23.92% 34.64%

1GB file 2GB file

Maximum waiting time

Total waiting time Maximum waiting time

Total waiting time

BIX 38m 53s 1hr 37m 50s 1hr 16m 8s 3h 14m 46s

BitTorrent (BT) 48m 8s 2h 11m 40s 1h 25m 56s 4h 25m 2s

Difference in % 23.79% 34.56% 26.01% 36.08

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Explanation

• BitTorrent has a solution for optimal path– Add information header

• Huge overhead, consume processing power

– Exchange groups of peers• Takes times, and may not be optimal

• Inter ISP policy– Connected every peers

• Fan-out to different ISP is large

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Conclusion

• BIX has better performance than BT• Functional:

– Better path– Concern of ISP policy

• Non-functional:– CPU usage– Setup time

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Future development

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HDTV Content Reduction

• 6GB for 1 Hour of HDTV content• Around 20% are commercials• Channel logo determines if it is a commercial

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HDTV Services

• TiVo is a leader in TV services– Automatic recording scheduler– Real-time TV pause– Large volume hard disk for long

playback• Easy to mimic• More advantage to share

through internet• No legal issues ( ReplayTV )

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Q & A