This research considers the question of what constitutes identities in cryptography. Typical

examples of identities include a person's name and social-security number, or fingerprint/iris-scan,

or address, or a (non-revoked) Public-Key coming from some trusted public-key infrastructure. In

many situations, however, where the person is located defines his or her identity. For example,

we know the role of a bank-teller behind a bullet-proof bank window not because he shows us his

credentials but by merely knowing his location. One of the questions that this research focuses

on is the following: is it possible to have the ""geographical position"" of a device take part in

defining the set of credentials this device has? What are the new possibilities in terms of what

can be achieved in this setting? First, this research examines the central task in this setting,

i.e., securely verifying the position of a device. Despite much work in this area, our preliminary

findings show that in the ""vanilla"" (i.e., standard) model, the above task of secure positioning is

impossible to achieve.

This research focuses on a different model: to study the proof of position in the bounded storage

model (i.e. where we assume some bound on the total memory of the adversary). In this setting,

this research aims to achieve various tasks including secure positioning, position-based key exchange,

and more general position-based secure functionalities. The broader impact of this project is to first id

entify various flaws in previous attempts; second, to propose a new framework where rigorous proofs

are in fact possible; third, to open this important area of research for further study by putting

it on solid theoretical foundations. The overall aim of this project is to develop a principled

approach to position-based cryptography, to define key problems, and to establish both impossibility

results and new frameworks that are provably secure.

Project Start
Project End
Budget Start
2007-09-01
Budget End
2010-08-31
Support Year
Fiscal Year
2007
Total Cost
$350,000
Indirect Cost
Name
University of California Los Angeles
Department
Type
DUNS #
City
Los Angeles
State
CA
Country
United States
Zip Code
90095