Proof of Data Distribution Based on Trusted Hardware

Abstract

We consider a scenario in which two parties prove to a third party that communication between them occurred. This can be seen in advertisement in which the data are distributed to the user by a distributor on behalf of owner. Specifically, we propose a protocol and a modification of it to address the possibility of collusion between the distributor and user in which the owner is deceived to pay for false claim of distribution, and the possibility of the user not providing any data transfer confirmation as an acknowledgement after receiving data. In the original protocol, the distributor and user are both equipped with trusted hardware. The data are encrypted and decrypted by this trusted hardware, with a shared secret key. When decrypting the data, the user's hardware generates a proof and sends it to the distributor. This proof is used as the proof of distribution to show to the owner for payment. This prevents the collusion with the help of the trusted hardware. This protocol assumes that the user will not misbehave and always send the proof back to the distributor. To address this issue, the modified protocol uses blockchain as a public ledger for the user to publish acknowledgement of receiving encrypted data chunk, and for the distributor to publish the corresponding secret for decryption. In both the protocols, we use the blockchain technology as a method for the ID management and payment.