ALPINe: Another Location Privacy Information Network

A portable device user, Alice, is travelling and wishes to get local information on points of interest (e.g. restaurants, hotels) from a location based service, but without a violation of her privacy. Furthermore, Alice wishes to maintain a presence at home. We present a system that allows a local user, either at her destination or in her home city, to act as a relay for Alice without revealing her identity either to the relay or to the location based service. The system relies on a central server and implements a reputation system to reward relays.