Investigating the DCF with Multiple Traffic Flows

The purpose of the 802.11 Distributed Coordination Function (DCF) is to allow multiple flows of traffic to contend for a shared wireless medium. In this application note, we investigate how the 802.11 Reference Design behaves when subjected to multiple traffic flows. This note provides a case study on how the WLAN Experiment Framework can be used to control and analyze the performance of the 802.11 Reference Design.

In this application note, we look at two things:

1. The effects of contention windows on medium access.
2. The effects of the hidden node problem on medium access.

This application note is not novel research. All of the insights provided here are known to the research community and have been for years. Instead, it is best to take this application note as an exercise of the WLAN Experiment Framework to re-discover known features of the 802.11 DCF.

Requirements

To run the code provided in this note, the following requirements must be met:

• 3 WARP v3 kits
• 802.11 Reference Design v.91 Beta