In the previous articles we have seen the technical characteristics of the blockchain and the function of the logs in the communication protocols, but there is only one blockchain managed model or the templates are more than one? What are the consequences of the fact that this is a distributed register?
Permissioned blockchain o unlimited blockchain?
A first classification of how to manage a blockchain is the one that refers to whether or not it is readable and readable by anyone or only of predetermined subjects (permissionless blockchain or permissioned blockchain).
It is also necessary to distinguish between:
premisses in access or read-only (eg by citizens who use the service and want to make a transaction but do not handle the node)
writing permissions that consist of the ability to engage the blockchain with the writing of a new block and which normally compete for who manages a network node (the miners).
It is clear that the two types of permissions are surely the second most important and delicate one for the security of the transactions you want to document.
An unobstructed blockchain from a log that can be accessed after identification, both in read and in writing, but does not require the existence of qualified people who manage it (theoretically the blockchain can “spin” on anyone’s computers and anyone can be a miner)
An authorized blockchain, on the other hand, is such as it only makes use of qualified subjects, and only runs on their respective computers, inserted into a certain closed network and known.
By doing so, going to analyze the blockchain technology from the point of view of the “computational work” needed to make it secure – three variants can be identified:
1. The blockchain we could call “PURE” – that is the totally open “bitcoin style” in which anyone can be a miner – and is based on proof of work that is an energetic system: the miners (and consequently the system costs) are paid in bitcoin with a percentage on the amount of value transferred with roof of work, since it is a “distributed” logically the transaction is accepted if it is confirmed by 51% of the nodes belonging to the chain
2. The block chain that we could call “LIGHT” – based on the Proof of Stake – that differs from the PoW as the miners are chosen with a system based on a certain “reputation” that a node has captured within the network. In practice, a “random” choice but at the same time “reasoned”. The system is much less energetic but it seems reasonable to be remunerated as above, however, it is a distributed system and even in this case the transaction is legally accepted if it is confirmed by 51% of the nodes belonging to the chain
3. The block chain that we could call “ULTRA LIGHT” – which is based on the fact that the “miners” are just known knots (belonging to the same organization). In this case no “test” is needed; it is sufficient that the node is realized, in fact the log management is centered on the organization that manages it and there is no need for any “referendum” confirmation of the transaction
If these are the three documented blockchain typologies, one wonders what the latter type of BC differs from a real public registry such as a Real Estate Register
– Existing IT real estate registers keep structured data over time in secure data from qualified entities
– real estate registers are kept and protected by the public system, because it is unlikely that someone will assume this role in the absence of a specific remuneration to support the whole system;
– the public officials (including notaries), the only ones able to modify the registry, have a function similar to the miners to verify the correctness of the link between the individual blocks and the certificate, and then create the new block that is entered in the log;
– the consent of only one public official is sufficient for the transaction to be approved.
It should also be borne in mind that blockchain-based systems store a very small amount of information, otherwise the computing power required for their management becomes unimaginable and anti-economic, this is the reason why they currently rely on systems based on that technology who want to trace not simply the transaction (transfer of property from A to B of money or other assets) but also the contract that justifies it or in any case the existence of a document (the source code of a sw), is only preserved ‘imprint of the document, but this does not preserve the risk of losing the do self-preservation and in that case the preservation of its sole imprint would be totally useless.Therefore, a system that really wants to ensure the traceability of the entire operation in addition to a blockchain that memorizes the hash must also include a preservation system for the document. At this point, we must carefully evaluate the actual savings of the entire process. Ultimately blockchain technology, by immutable definition, may seem strange, but this characteristic is badly compatible with a typical requirement of public registers of legal value and relative to complex transactions such as real estate, or the need for the state to retain the power / duty to “say the last word”, that is, the power to act imperiously on the results of the register, even in disparities and modifications to it (think of the necessity of exercising the power of the court, which in some cases must be able to change the register’s findings.) This seems impossible in rigid systems like those totally computerized, which (by definition) are based on the principle of “non-alteration of the data”.
Distributed register: democracy or ologopoly?
We have pointed out earlier as in the “distributed” registers By providing a central authority that manages them and guarantees the content, transactions must be approved by 51% of the nodes who compare the data in their possession and proceed to the creation of a new block by incorporating the new transaction only if this conflicts with the previous transactions. This system is based on two pillars: the network decentralization, that is, its being actually distributed among many subjects that handle each one an integral replica of the register and to engage new transactions, the correctness of the miners, now supported by the a mechanism borrowed from Bitcoin’s basic theory of major dangers is just the centering of computing power in the hands of few: only a few years ago (2012) Deepbit alone controlled 45% of the hash power and with only BTC Guild could have coalitioned the absolute majority of votes; mining distribution has now improved over the years, but this does not mean that this is one of the vulnerabilities of the system, given that most of the computing power is currently allocated to China and India and only to a small extent in America’s north and in Europe.
