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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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