摘要 |
In one embodiment, a method includes sending, by a first wireless device associated with a first user, first data such that the first data are only available to one or more second wireless devices respectively associated with one or more second users and within a first distance from the first wireless device. The method further includes sending, by the first wireless device associated with the first user, second data such that the second data are only available to one or more third wireless devices respectively associated with one or more third users and within a second distance from the first wireless device. |