Resource pricing and the evolution of congestion control

By R. J. Gibbens and F. P. Kelly

A proportionally fair pricing. A fair distribution according to a price the

user is willing to pay.

Why ?

How ?

Rates according to shadow pricing

• Let

• Then The change in the rate is:

Rates according to shadow pricing

• If w(t) = wr Then the stable point of the system is :

A proportionally fair per unit charge.

Congestion Mechanisms

• Creating various measurements and congestion control algorithms in the network itself (routers).[floyd and fall]

• Creating incentives for the end nodes to use congestion control –

charge aware TCP

Different approaches to charge aware TCP

• Paris metro pricing

• Smart market

The Expected Cost and Shadow price

The Expected Number of marks

When distribution is more general

Thus

Congestion Algorithm 1 the Elastic User(w)

Where

Congestion algorithm 2File Transfer(F,W)

Elastic User that changes the Payment.

Comparison with the Internet Packet conversation principle

A new packet isn’t put into the network until the old packet leaves

=self clocking

Current congestion algorithm disadvantages

• Not user specific.

• Dropping packages is an extreme mechanism for congestion control.

• The rate at which the signals a generated in the source.

Response of end-nodes to Congestion

• Jacobson – Average Rate

• Elastic user - Inverse proportion to

Jacobson Average Rate in our Equations

• If the user needs the average rate of Jacobson than the utility function

would produce that rate.

Self Clocking in our Equations

When no congestion indications are present

File-transfer is doubling it’s rate

(with proportion to T).

Self Clocking in our Equations

• Elastic User can be self clocking if cwnd increased by

• So the change in the rate is :

Game Theory Model

• If the user is price-aware he will maximize:

• The solution is

When

Game TheoryThe average paying is

When r= is constant and equal Then

Conclusion – users shade their bids if they have market power

Concluding remarks

By appropriately marking the resources

end-nodes are provided with the necessary

information to make efficient use of the

network resources