On the Design of the TCP/AQM Traffic Flow Control Mechanisms

Several aspects of the TCP/AQM system design are discussed that may affect performance of the network. Namely, due to decentralized structure of the network traffic flow control system in which traffic rate control tasks are delegated to autonomous agents, it may be possible for the agents to profitably re-engineer the TCP congestion control algorithm at the cost of the overall performance of the network. In this paper it is shown how the commonly applied TCP/AQM design procedures may give rise to mechanisms that are prone to attacks discreetly moving the network traffic flow away from the desired operating point. Furthermore, a short discussion is presented concerning the countermeasures that can be taken to reduce these effects.