Introduction
Introduction to Proof of Location
Currently in Development.
Proof of Location is a decentralised proof of "geolocation" which can be used to validate the geographic location of a "prover" device connected to Internet.
Protocol Description
In Proof of Location a prover claims a geographic location. The challengers then validate the geographic location of the prover. Proof of Location makes use of Internet delays for geolocation. The protocol consists of two steps,
Calibration Phase
The protocol comprises a prover, whose location is to be validated and the set of challengers, whose location are known a priori
In calibration phase, the challengers measure Internet delay to each other via application layer UDP pings
A challenger then calibrates delay to distance mapping for itself using the delay measurements and the location of other challengers
Measurement Phase
In the measurement phase, the location claim of the prover is validated
The challengers measure delay to the prover using application layer UDP pings
Using the delay to distance mapping obtained during calibration phase, each challenger outputs a region where the prover can be present
Our protocol aggregates the output across different challengers and then outputs the maximum distance that the prover can be from its claimed location
Parties Involved
Payer: A party who pays for the challenge and starts one
Prover: The device connected to Internet whose location needs to be validated
Blockchain full-node: Decentralised ledger for recording all the challenge requests and outcomes
Challengers: A pool of servers that validate the location claim of the prover
Challenge coordinator: Centralised services for (i) communication between the parties; (ii) computing challenge meta data; and (iii) interacting with the ledger
Functional description
Functionally the different components involved in Proof of Location challenge are similar to that of Proof of Backhaul. The different steps in a Proof of Location challenge remain similar to the Proof of Backhaul, except during challenge execution, the measurement phase described above to validate prover's location is carried out instead of measuring the backhaul in Proof of Backhaul.
Trust and Threat Model (current)
The trust assumptions for challenge coordinator remain same to Proof of Backhaul
Prover
The prover can claim a false location
The prover can inflate the ping delays to the challenger during measurement phase of challenge execution
Challengers
In current version of Proof of Location, the challengers are trusted.
They report their correction location
They do not inflate delays to other challengers in calibration phase
They use a correct delay to distance mapping in measurement phase
In future, our Proof of Location protocol will be able to tolerate a certain fraction of adversarial challengers, where the above trust assumptions will be relaxed
Last updated