Proving your identity can often be a persistent problem for migrants and refugees. Could blockchain technology - the system that supports the virtual currency bitcoin - offer a solution? The project is called ID2020, and it aims to use so-called blockchain technology to ensure every child born after 2020 has a self sovereign digital identity. ID2020's founder is John Edge. What exactly is a self-sovereign identity?

Photo credit: Migrants wait at the Trnovec border crossing as restrictions on movements through have produced bottlenecks on Croatias borders on October 19, 2015. Jeff J Mitchell/Getty Images