Privacy-preserving management of transactions' receipts for mobile environments

Users increasingly use their mobile devices for electronic transactions to store related information, such as digital receipts. However, such information can be target of several attacks. There are some security issues related to M-commerce: the loss or theft of mobile devices results in a exposure of transaction information; transaction receipts that are send over WI-FI or 3G networks can be easily intercepted; transaction receipts can also be captured via Bluetooth connections without the user's consent; and mobile viruses, worms and Trojan horses can access the transaction information stored on mobile devices if this information is not protected by passwords or PIN numbers. Therefore, assuring privacy and security of transactions' information, as well as of any sensitive information stored on mobile devices is crucial. In this paper, we propose a privacy-preserving approach to manage electronic transaction receipts on mobile devices. The approach is based on the notion of transaction receipts issued by service providers upon a successful transaction and combines Pedersen commitment and Zero Knowledge Proof of Knowledge (ZKPK) techniques and Oblivious Commitment-Based Envelope (OCBE) protocols. We have developed a version of such protocol for Near Field Communication (NFC) enabled cellular phones.