It would be safe to say that practically every form of Vipassana Meditation is based on the Satipatthana Sutta in some way or another. People who teach watching the in and out breath, either at the nostrils or the belly, body sweeping, noting, mindfulness, and choice-less awareness, to name the most common techniques, will most likely attest that their root instructions are found in this discourse. But is that what the discourse states as a way to meditate?
The sitting meditation instruction is literally (From my translation of the Satipatthana Sutta):
into the woods,
or under the shade of a tree,
or inside an empty house,
having created a lap,
setting his back upright,
holding his attention
around his face.
Once the meditator finds a suitable place to sit, he simply sits upright and brings his attention around his face. From that vantage point, breathing is known. But so are sensations, feelings, and thoughts. It is just that the breath is mentioned first. It makes logical sense that if we bring our attention to the front of our face, we will immediately become aware of breathing. But, I would say, the purpose is not to become only aware of breathing. Rather, to become open to whatever arises when you sit down to meditate. The seated meditation posture is then a foundation, a base, a place for one’s attention to land, even though it can’t remain there if one is going to allow thoughts and emotions into the meditation sitting, which are some of the other fields of awareness the Buddha advocates.
The other three fields of awareness (besides the body) are moods within feelings, states of consciousness within thoughts, and fundamental truths within mental processes. They are anupassana. To me that means the meditator is looking at, within, around, and underneath her experience. Feelings, thoughts and mental processes have dimensions to them, depth and breadth, a history, a present manifestation, and a momentum or trajectory forward. They are not static fields of awareness but rather large expanses of changing territory to explore.