BFastPay

Bitcoin is the most popular cryptocurrency which supports payment services via the Bitcoin peer-to-peer network. However, Bitcoin suffers from a fundamental problem. In practice, a secure Bitcoin transaction requires the payee to wait for at least 6 block confirmations (one hour) to be validated. Such a long waiting time thwarts the wide deployment of the Bitcoin payment services because many usage scenarios require a much shorter waiting time. In this paper, we propose BFastPay to accelerate the Bitcoin payment validation. BFastPay employs a smart contract called BFPayArbitrator to host the payer's security deposit and fulfills the role of a trusted payment arbitrator which guarantees that a payee always receives the payment even if attacks occur. BFastpay is a routing-free solution that eliminates the requirement for payment routing in the traditional payment routing network (e.g., Lightning Network). The theoretical and experimental results show that BFast is able to significantly reduce the Bitcoin payment waiting time (e.g., from 60 mins to less than 1 second) with nearly no extra operation cost.