With extra bandwidth and time for adjustment tcp is competitive
This presentation is the property of its rightful owner.
Sponsored Links
1 / 30

With Extra Bandwidth and Time for Adjustment TCP is Competitive PowerPoint PPT Presentation


  • 59 Views
  • Uploaded on
  • Presentation posted in: General

With Extra Bandwidth and Time for Adjustment TCP is Competitive. J . Edmonds, S . Datta, and P . Dymon d. TCP (Transport Control Protocol) AIMD (Additive Increase, Multiplicative Decrease). Email Web Telnet. File Size. Arrival time. Many Packets » Data Flow.

Download Presentation

With Extra Bandwidth and Time for Adjustment TCP is Competitive

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


With extra bandwidth and time for adjustment tcp is competitive

With Extra Bandwidth and Time for AdjustmentTCP is Competitive

J. Edmonds, S. Datta, and P. Dymond


Tcp transport control protocol aimd additive increase multiplicative decrease

TCP (Transport Control Protocol)AIMD (Additive Increase, Multiplicative Decrease)

  • Email

  • Web

  • Telnet


Input set of sender jobs

  • File Size

  • Arrival time

  • Many Packets » Data Flow

Input: Set of Sender/Jobs


Bottleneck capacity and adjustments

Adjustments

B

b

b

,t

,t

(not buffer

or time delay)

Bottleneck Capacity and Adjustments

å£

B


With extra bandwidth and time for adjustment tcp is competitive

b

,t

TCP (Transport Control Protocol)AIMD (Additive Increase, Multiplicative Decrease)

A=1

c=½

Multiplicative

decrease

Additive

increase

Time


Evaluating tcp

  • Throughput & packet loss rate

- arrival )

(completion

AVG

  • “User Perceived Latency” or “Flow Time”

Evaluating TCP

  • Good observed performance

  • Simulation of approximate models

  • Few theoretical results

    • [KKPS] 20 Questions to “guess” allocation

  • Fair to all Users

  • [CJ] Single-bottleneck:TCP fair

  • [F] Multi-bottleneck: TCP not fair


User perceived latency flow time

a

a

c

c

,

, … ,

,

,

,

,

,

Bad(J) =

Good(J) =

J = {

}

- a )

- a )

(c

(c

AVG

AVG

Bad(J)

Good(J)

User Perceived LatencyFlow Time

n Long

n

»

»

=

(n-1)e + Long


Comparison with other schedulers

TCP

  • [CJ] TCP ÞEQUI

EQUI

B

B

B

Shortest

Remaining

Work First

  • Optimal

Comparison with other Schedulers


Knowledge of scheduler

All Knowing

All Powerful

Optimal:

?

Future

Online:

?

Non-Clairvoyant:

TCP

?

Distributed:

Knowledge of Scheduler


Not competitive

Not Competitive


Competitive

Competitive


Previous results batch

a

EQUI(J)

[MPT]

£ 2

OPT(J)

[ECBD]

£ 3.73

Previous Results(Batch)


Previous results lower bounds

a

a

a

a

a

EQUI(J)

[MPT]

³W(n)

OPT(J)

NonClair(J)

³W(n½)

OPT(J)

Previous Results(Lower Bounds)


Previous results upper bounds

BAL1+e(J)

[KP]

£ O(1/e)

OPT1(J)

EQUI2+e(J)

[E]

£ O(1/e)

OPT1(J)

BROADCAST4+e(J)

[EP]

£ O(1/e)

OPT1(J)

Previous Results (Upper Bounds)


New results

£ O(1)

Adj

Adj

Adj

TCPO(1)(J) - Adj

TCPO(1)(J)

TCP(J)

q

q

OPT(J)

OPT1(J)

OPT1(J)

New Results


Proof sketch

EQUI2+e(J)

[E]

£ O(1)

OPT1(J)

Reduction

Proof Sketch


Tcp equi

TCP

  • TCP ÞEQUI

EQUI

B

B

TCP Þ EQUI

[CJ] global measure

New: Job by job comparison


Proof sketch1

b

,t

Proof Sketch

Unadjusted

Adjusted


Proof sketch2

b

A=1

c=½

,t

Time

Unadjusted

Adjusted

TCP³ (1-cq) EQUI

b

b

,t

,t

at ,

After q ,

Proof Sketch


Proof sketch3

TCPO(1)

EQUI

c=½

TCP

TCP³ (1-cq) EQUI

b

b

b

b

b

b

b

,t

,t

,t

,t

at ,

After q ,

,t

,t

,t

TCPO(1)³EQUI

Proof Sketch


Proof sketch4

Proof Sketch

EQUI


Proof sketch5

Proof Sketch

EQUI


New results1

TCPO(1)(J)

TCPO(1)(J)

TCP(J)

£ O(1)

OPT(J)

OPT1(J)

OPT1(J) + Adj

New Results


Proof sketch6

TCPO(1)

EQUI

Less

J’

£

TCPO(1)(J)

EQUI2+e(J’)

£

£ O(1)

OPT1(J’)

OPT1(J’ )

b

b

Adj

OPT1(J)

+

+

,t

,t

Proof Sketch

J


Proof sketch7

TCPO(1)

EQUI

Less

J’

TCPO(1)(J)

EQUI2+e(J’)

£

£ O(1)

OPT1(J’)

OPT1(J’ )

b

b

Adj

OPT1(J)

+

+

,t

,t

³

³ Less =

Proof Sketch

J


Proof sketch8

TCPO(1)

EQUI

Less

Less

Less

Adj

Adj

Adj

q

q

b

b

,t

,t

Less£ Adj

Proof Sketch


Proof sketch9

Less

Adj

q

Less£ Adj

Proof Sketch

EQUI


Proof sketch10

TCPO(1)

EQUI

Less

J’

TCPO(1)(J)

EQUI2+e(J’)

£

£ O(1)

OPT1(J’)

OPT1(J’ )

b

b

Adj

OPT1(J)

+

+

,t

,t

³ Less =

Proof Sketch

J


Proof sketch11

TCPO(1)

EQUI

Less

J’

TCPO(1)(J)

EQUI2+e(J’)

£

£ O(1)

OPT1(J’)

OPT1(J’ )

b

b

Adj

OPT1(J)

+

+

,t

,t

Proof Sketch

J

Done


Conclusion

RecentResult

Conclusion

TCP is Competitive


  • Login