Introduction of a New Method for Preventing Recipient Unapproved Transactions to Bitcoin Wallet

Abstract

Bitcoin is one of the typical cryptocurrencies. Cur-rently, Bitcoin allows unilateral sending of currency by the sender (payer of currency) regardless of the presence or absence of intention of the recipient (payee of currency). Previous works pointed out that this could induce the sending of currency used in crimes, etc., which could lead to problems. This problem is called the recipient unapproved problem. Bitcoin users use a function called Bitcoin wallet in the platform software such as Bitcoin Core to perform transactions. In this paper, we try to incorporate a new transaction creation method into the Bitcoin wallet in order to resolve the recipient unapproved problem. The new transaction creation method also allows the recipient's Bitcoin wallet to participate in the creation of the transaction, and adds the recipient's digital signature to prove that the transaction was also approved by the recipient and a new address that cannot be used except for approved transactions. In experiments for investigating the overhead of the new transaction creation method, results showed that a transaction can be created with about twice creation execution time of the conventional transaction creation method.