Policy-oriented AQM Steering

Detecting and handling network congestion in the Internet has, again, become a vital area of research. The provisioning of low latency together with high throughput is of particular interest due to the current mix of applications running in the Internet. Active Queue Management (AQM) mechanisms come with the promise of reducing queuing delays. They, however, may adversely affect throughput and network utilization and have proven to be difficult to configure. More recent AQMs, such as CoDel, PIE, and GSP are easier to configure but work with a fixed target delay setpoint. Depending on the traffic the same setpoint value can result either in unnecessary large delays or under-utilization of the link. Policy-oriented AQM Steering automatically adapts the target delay setpoint to the current traffic situation, in order to fulfill a given quality-of-service policy. Such a policy consists of a utilization goal and an upper delay bound. This improves AQM performance with varying traffic situations and makes the impact of deploying an AQM predictable. A prototypical implementation of AQM Steering for GSP showed its performance advantages compared to static AQM variants at speeds of 10 Gbit/s and 1 Gbit/s.