Paper Review:
Charge-Sensitive TCP and Rate Control in the Internet

Reviewer: Jie Zhou


Because Internet is a public domain and its participants potentially do not act cooperatively, we need to design a pricing mechanism for Internet. Previous approaches including flat rate charging is found to have the problem of ineffeciency. A desirable system should not only be fair, but also allocate the available bandwidth in such a way that maximize the total utility of users.


The paper investigates the fundamental problem of achieving the system optimal rates in a distributed environment.And it introduces an algorithm that may be deployed over the Internet without significant modification within the network.

Main Ideas

  • The system optimum is achieved at an equilibrium, when users update their parameters by solving their own optimization problem.
  • In the case of a single bottleneck, there exists a unique Nash equilibrium, and the equilibrium approaches the system optimum as the number of users increases.


    This paper is developed upon Kelly's suggestion that the problem of achieving the system optimum can be decomposed into two subproblems: network and user problems. And the algorithm in the paper is an extension of an algorithm introduced J.Mo and J. Walrand. Though it is not original, the paper provides some insight into achieving system optimum in terms of both fairness and total utility. So I give it a rating of 3 (modest contribution).


    Due to the size of the Internet, an algorithm that requires an extensive modification inside the network may not be suitable for deployment.