Traffic shaping, also known as Quality of Service (QoS), is a means of prioritizing network traffic that meets certain criteria. Without traffic shaping, network traffic is processed on a first-in, first-out (FIFO) basis. While in many cases, processing network traffic in such a way may be adequate, in other cases, it may lead to links becoming saturated, which in turn can lead to buffering and increased latency. Traffic shaping provides us with a means of prioritizing certain network traffic, which guarantees that it will receive available bandwidth before lesser priority traffic.
pfSense has its own traffic shaper, which is not only useful, but is also extremely easy to use. The pfSense traffic shaper wizard is easy and quick to configure, and the process of setting up traffic shaping can be done in a matter of minutes. In this chapter, however, it is our objective to provide a basic understanding of traffic shaping before delving into the specifics of how to implement traffic shaping in pfSense. Sometimes, pfSense's built-in traffic shaping functionality is not enough to meet our requirements, and in those instances, we must rely on third-party packages. We will cover that scenario as well.
In this chapter, we will cover the following topics:
- Traffic shaping essentials, including a summary of different queuing disciplines
- Configuring traffic shaping in pfSense, including using the pfSense traffic shaping wizard, as well as manual queue and rule configuration
- Some real-world traffic shaping examples
- Using Snort for traffic shaping
- Troubleshooting traffic shaping