In 2008, the Estonian government began experimenting with and testing this new technology before Satoshi had even released his/her whitepaper. At this time, the term “blockchain” had yet to be coined, and the Estonians referred to it as “hash-linked time-stamping.” Since 2012, hash-linked time-stamping, or blockchain, has been in operational use in many of Estonia’s registries, such as national health, judicial, legislative, security, and commercial code systems.
The X-Road is the open-source backbone upon which the country’s entire digital infrastructure runs. First put into practice in 2001 (it’s been upgraded and altered many times since), X-Road is rooted in a blockchain called K.S.I., which was developed by Guardtime, one of the biggest blockchain companies in the world. K.S.I. is incidentally used by both NATO and the US Department of Defense.