The failure earlier this year of Tokyo-based bitcoin exchange Mt. Gox may have stirred Japanese doubts about the credibility of the digital currency.

But despite its demise, many people worldwide view bitcoin technology as a world-changing innovation. Among them is Takafumi Horie, 42, former president of Internet firm Livedoor Co.

There have been many digital currencies and monetary services, including Suica, Rakuten Edy and Internet banking, but they are basically centralized and managed by certain companies or organizations.