[stelfer]

Most people associate "blockchains" with a protocol by which the "blocks" are inserted. Usually these things revolve around proof-of-work, proof-of-stake, proof-of-space, fairness criteria, etc. I think everyone gets that the Guardtime product is hashtree. From a formal verification perspective, the critical behavior is probably in the protocol, and most likely not the implementation of the datastructure or database.

[ristoalas]

One way to look at it is that KSI is a proof of stake blockchain where the stakeholders are (mostly) fixed. Often people would call that a private blockchain (or a consortium blockchain), to use the terminology from the following article:

https://blog.ethereum.org/2015/08/07/on-public-and-private-b...

[unboxed_type]

Thanks for that clarification! It is a great pleasure to talk with an knowledgeable person like you.