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Receiver
TCP
Sender
TCP
RED queuing
drop-tail queuing, or
Link with constant delay,
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FACK RH DA
Simulation bits/s
Model bits/s
5
1e+05
2
5
1e+06
2
5
1e+07
2
5
1e+08
2
5 1e+05 2 5 1e+06 2 5 1e+07 2 5 1e+08 2
FACK RH DA
With Timeouts
Model, C=1
BW * RTT/MSS
loss (p)
0.5
1
2
5
10
20
50
100
200
2 5 0.0001 2 5 0.001 2 5 0.01 2 5 0.1 2
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Min Reno DA
Model, C=1
BW * RTT/MSS
loss (p)
0.1
0.2
0.5
1
2
5
10
20
50
100
0.0001 2 5 0.001 2 5 0.01 2 5
Reno DA
Model, C=1
BW * RTT/MSS
loss (p)
4
5
6
8
10
15
20
25
30
40
50
60
80
100
0.0001 2 5 0.001 2 5 0.01 2 5
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L
S1
S2
R1 K1
8Mbps
Variable delay =
5ms
8Mbps
TCP 2
TCP 1
0.8Mbps
100ms
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FACK RH
FACK RH DASack1
Sack1 DA
Reno
Reno DA
New Reno
New Reno DA
Tahoe
Tahoe DA
Proportion
loss (p)
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
5 0.01 2 5 0.1 2 5
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TReno
(Timeouts)
Model, C=1
BW * RTT/MSS
Loss Rate (p)
0.3
0.4
0.5
0.7
1
1.5
2
3
4
5
7
10
15
20
30
40
0.001 2 5 0.01 2 5 0.1
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Set 1
(Timeouts)
Model, C=1
BW * RTT/MSS
loss (p)
5
6
7
8
10
15
20
25
30
35
40
50
60
70
80
0.0001 2 5 0.001 2 5 0.01
Set 2
(Timeouts)
Too short
Model, C=1
BW * RTT/MSS
loss (p)3
4
5
6
8
10
15
20
25
30
40
50
60
80
2 5 0.001 2 5 0.01 2
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2
4
gatewaysource sink
11
1
00
2
2 3
3 3 4 4 5
5
5
0
: 1.5Mbps, 50ms delay
: 10Mbps, 5ms delay
1a 1b 2a 2b 3a 3b 4a 4b 5a 5b
Queue Length = 5 packets)
(50 ms, Lossy Link)
Link, L
Router
1000 WWW servers
Data Center
Router
1000 Users
University User
(10 Mb/s ethernet)
(28.8 kb/s,
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CA-Events
Modem RTT
Loss at L
Loss at Modem
Total Loss
Loss rate (%) or RTT (units of 1/10 second)
loss (p) at link L
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
11.00
12.00
0.001 2 5 0.01 2 5 0.1 2 5
mss=4312
mss=1460
mss=536
Modem
Simulation Bandwidth (b/s)
loss (p) at link L200
500
1e+03
2
5
1e+04
2
5
1e+05
2
5
1e+06
2
5
1e+07
2
0.001 2 5 0.01 2 5 0.1 2 5 1
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