An Efficient Dropper Design for Implementing Capacity Sharing with Congestion Exposure

Capacity sharing - the fair usage of the available capacity amongst a set of users - is relying solely on the end user/end hosts in today´s Internet. This in principle allows malicious end users to consume disproportional amounts of capacity without obvious ways of stopping or charging them. Re-ECN is a resource sharing framework that enables such resource usage accountability by, amongst other things, employing enforcement points in the network. These are often described as packet droppers at or near the egress of an end-to-end path. This paper presents a packet dropper design that allows implementing the required congestion declaration enforcement efficiently. Our dropper design is based on a hybrid approach providing the effectiveness close to a complete stateful flow monitoring with the efficiency of a more stateless approach. We evaluate the effectiveness and the resource requirements through simulation.