摘要 |
A first and second secure location indicators are electronically received at one or more servers from a first portable computing device and a second portable computing device, respectively, operating in a wireless communication network. Each of the secure location indicators is generated using the location of the corresponding portable computing device, and neither secure location indicator reveals the location of the corresponding portable computing device to the one or more servers. The first secure location indicator is compared to the second secure location indicator at the one or more servers and, in response to determining that the first secure location indicator is identical to the second secure location indicator, an indication of physical proximity of the second portable computing device is electronically transmitted to the first portable computing device. |