The network is a crucial part of the infrastructure, but it is only a part of it. What the users care about is often the service that runs on top of the network. If the user is trying to watch a YouTube video or listen to a podcast but cannot, in their opinion, the service is broken. We might know that it is not the network transport, but that doesn't comfort the user.
For this reason, we should implement tests that are as similar to the user's experience as possible. In the example of a YouTube video, we might not be able to duplicate the YouTube experience 100% (unless you are part of Google), but we can implement a layer-seven service as close to the network edge as possible. We can then simulate the transaction ...
