A BAN system includes multiple terminal apparatuses connected by wireless communication, where a terminal apparatus of the multiple terminal apparatuses is configured to identify in which direction acceleration has changed, the direction being identified based on a measurement result of a sensor of the terminal apparatus, the sensor being configured to measure acceleration and to refer to information that specifies corresponding to places where the plurality of terminal apparatuses is to be attached to a body, directions in which acceleration changes when the body performs a given behavior, and determines based on the identified direction, a place where the terminal apparatus is attached to the body.