Date Added: Feb 2011
The authors propose a framework for formal analysis of privacy in location based services such as anonymous electronic toll collection. They give a formal definition of privacy, and apply it to the VPriv scheme for vehicular services. They analyze the resulting model using the ProVerif tool, concluding that their privacy property holds only if certain conditions are met by the implementation. Their analysis includes some novel features such as the formal modelling of privacy for a protocol that relies on interactive zero-knowledge proofs of knowledge and list permutations.