HTTP is not the only protocol on our networks that we need adequate bandwidth for. For example if we have online games or voice and video communication on our network, these services usually warrant higher priority than others due to their time-sensitive use. You wouldn't want to have a choppy voice conversation with a client because one of the users on the network is downloading large files, or on a home network, you wouldn't want to lose your high score in your online game because someone decided to start listening to their online radio station. This is where traffic shaping comes in.
In order to ensure Quality of Service (QoS), we have to control traffic so that high priority traffic is treated as just that, high priority! With traffic shaping, we can use all the same parameters we use in packet filtering; however, instead of deciding whether to pass the traffic, we make more complicated decisions about which traffic is afforded...