STAMP

Abstract

Location-based services are becoming immensely popular. In addition to services based on users' current
geographical location, many potential services rely on users' geographical location history, or their spatial-temporal
provenance. Malicious users may lie about their spatial-temporal provenance without a carefully designed security
system for users to prove their past locations. In this paper, we present the Spatial-Temporal provenance Assurance with
Mutual Proofs (STAMP) scheme [1]. STAMP is designed for ad-hoc mobile users generating location proofs for each
other in a distributed setting. However, it can easily accommodate trusted mobile users and wireless access points.
STAMP make sure the binding and non-transferability of the geographical location proofs and protects users' privacy. A
semi-trusted Certification Authority is used to distribute cryptographic keys as well as guard users against collusion by a
light-weight entropy-based trust evaluation approach. Our prototype implementation on the Android platform shows that
STAMP is low-cost in terms of computational and storage resources [2]. Extensive simulation experiments show that our
entropy-based trust model is able to achieve high collusion detection accuracy.