A distributed fair congestion avoidance protocol

Congestion is a particular problem in computer networks because all nodes compete with each other for the available resources. If congestion occurs, packets cannot be delivered anymore and the achieved data rate decreases significantly for all nodes. Different approaches for congestion avoidance and control exist. Nevertheless, a new proactive approach that works independent of the congestion control or avoidance capabilities of Transport Layer protocols and the available resources may be superior. In this paper, we present DiFCAP, a proactive Distributed Fair Congestion Avoidance Protocol that works independent of the congestion handling capabilities of Transport Layer protocols and the available resources. DiFCAP uses a transmission notification mechanism that leads to fair throttling of outgoing transmissions of all nodes within a predefined group. Thereby, congestion can be partially avoided and the packet drop rate can be reduced. The performance improvements that can be achieved using DiFCAP are shown through simulations.