Variable precision location sharing

摘要

A secure location sharing system is disclosed that allows publishers to share their locations with subscribers. Each publishing device generates, encrypts and publishes its location information with a specified precision to a distribution service for distribution to one or more subscribing devices. The distribution service provides secure distribution of the location information to the distribution list but cannot access the publisher's precise location information, which remains encrypted until decrypted at the subscribing devices. Publishers can share their location information with varying levels of precision for different subscribers. Publishers can select at least two dimensions of location information precision: spatial and temporal. For less precise location sharing, the publishing device can randomize or otherwise obscure the precise location of the publishing device. The publisher can move a subscriber or a group of subscribers to a lower or higher level of location precision by generating new key pairs at the publishing device.

主权项

1. A computer implemented method performed by one or more hardware processors of a mobile device, the method comprising:
obtaining location information describing the location of the mobile device; receiving a specification of (i) a precision of the location information and (ii) a trigger event on the mobile device, the precision being specified in the form of a precision value among a range of precision values, and the trigger event being specified as an occurrence of either a phone call carried out by the mobile device or an entry on a calendar associated with the mobile device; modifying the location information based on the specified precision; choosing an encryption key among a plurality of encryption keys each associated with a respective precision, wherein the chosen encryption key is associated with the specified precision; encrypting the modified location information using the chosen encryption key; detecting the trigger event by determining the occurrence of either the phone call or the calendar entry; and in response to the detecting of the trigger event, publishing, during the occurrence of either the phone call or the calendar entry, the encrypted location information to a distribution service for distribution to one or more subscribers.