A blockchain based peer-to-peer framework for exchanging leftover foreign currency

Almost every traveller possesses some amount of leftover foreign currency, either as actual cash or on a travel currency card, at the end of any international trip. However, the means to exchange this leftover currency, coins in particular, is largely inconvenient often leading to considerable amounts discarded or left unused. In this paper, we explore how distributed ledger technology, i.e. blockchain, could be applied to the problem of utilizing this leftover foreign currency. We portray here the drawbacks of the existing systems of foreign currency exchange and delineate the requirements of a potential mobile web application for exchanging this currency by integrating smart kiosk based systems, particularly for handling cash, with a peer-to-peer currency exchange technique based on blockchain that could help to bring such currency back into circulation efficiently.