1 buddy internet exchange lyu0701 supervisor: professor michael r. lyu prepared by: kwong kwok wai -...
Post on 19-Dec-2015
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1
Buddy Internet ExchangeLYU0701
Supervisor:Professor Michael R. Lyu
Prepared By:Kwong Kwok Wai - 06545093
Chan Kwan Ho - 06837554
2
Review of first term
• Focus on thetransport-layer :Application independent
• Network topology discovery could have further benefits to P2P applications
3
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
4
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
5
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.
7
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
8
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
9
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
10
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
12
Algorithm design
• Goal– Smallest total waiting time (Main Idea)– Smallest maximum waiting time
• Cannot obtain both when huge number of ADSL users.
13
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
14
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
15
Algorithm design
• Peers selection– Inter Peers Network Status Matrix (IPNSM)
]))[],[min(
(lim],[
,
downLinktoPeeruploadLinkfromPeer
sourceflowtoPeerformPeermatrix
toPeerpeersformPeerpeers
16
Algorithm design
• Peers selection– In order of sorted list– Find the highest output node using IPNSM– Update IPNSM
]),[,min(
],[
ierselectedPematrixlectedPeeroutputToSe
ierselectedPematrixi
17
Algorithm design
• Utilize non optimal link– Travel starts from leaf node– Connect to non optimal node in higher level
])[][&0][(
...
downloadthisdownlinktestNodeuplinktestNodeif
testNodeleafparentparentthisSelectNode
18
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
19
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
20
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
21
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
22
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
23
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
24
Conclusion
• BIX has better performance than BT• Functional:
– Better path– Concern of ISP policy
• Non-functional:– CPU usage– Setup time
26
HDTV Content Reduction
• 6GB for 1 Hour of HDTV content• Around 20% are commercials• Channel logo determines if it is a commercial
27
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 )