DevConf: a little about blockchain

May 18 in Digital October (Moscow) will host a conference of web developers DevConf. Grigory Kochanov will tell about the blockchain. Frankly, I am a skeptic of all this HYIP, so I asked him a little.

Let's start with this question. Where do you think blockchain as technology will be in 5 years. To which point is closer: Will the world conquer or be forgotten?

This is a HYIP, but this is not PR of one company, as with ROR or Mongo. Blockchain is an architecture topology for distributed applications. Nothing new - according to the CAP theorem, this is the CP class consistency-partition tolerance architecture. For comparison, a DBMS is a class CA (consistency-availability). This tool is convenient for solving a number of problems, and it will be used.

Do you believe that after some time everyone will have a cryptocurrency wallet?

Cryptocats are like bonus cards in stores, they have a similar economic model. There is such a thing - an additional currency .

Companies have always issued bonuses, points, coupons, cards. On the blockchain, it's convenient to do this on a large scale. From the new here is only the Internet, and tokens appeared in paper and metal form in the Middle Ages.

Why convenient on a large scale? Is this something like a convenient replication where there are many masters?

Imagine that you are designing a system of bonus cards for a network of supermarkets.

The usual solution: a data center, a cluster of database servers, replicas in the regions for unloading, access by API.
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A server or a router on the main line broke down - and in half of the country, the ticket office does not work. There was a recent case with online cash registers, for example.

With blockchain, the principle is different. Each supermarket has its own server, with a replica for reliability. The client holds a key on the card, carries it out with a card - signs the transaction. All transactions are replicated to all servers. There is no single point of failure. Datacenter is not needed. You can use a couple of computers in the server rooms of the supermarkets themselves. Each supermarket itself produces cards, charges and debits bonuses for purchases. Employee fraud is possible, but hide it will not work.

When there is no connection, transactions can still be processed. As an option, only for crediting bonuses. Synchronization will take place later.

A physical card is optional, you can use a phone with NFC.

When such a solution appears with a simple interface, every street point of coffee can make its own currency for settlements for coffee.

Many speak of decentralization as a huge plus, but I immediately recall the congress of the main miners of Bitcoin and the fork of Etherium. Where there are people, there will always be workarounds. 51% attack? Or is it all wrong?

There is technology, there is implementation. Whether it is necessary to comply with a smart contract to the detriment of the community, the problem of the trolley, the primacy of matter or the thought of whether there is life on Mars - I do not care, I am an engineer and economist.

Blockchain is replication. Normal database replication by API. The general rule works: if you want to speed up the system - increase memory consumption, if you want protection from failures - make copies. No philosophy.

The 51% attack is not really worth being feared. Foreign coins can not be picked up even with 90% hashrate. You can split the network, bring down the price. This is one of the reasons why ethereum is planning to abandon mining.

Many still talk about the industrial blockchain, but I see a very narrow range of its application (contracts and some interbank transactions). Do I understand correctly that blockchain is immutable, but always open to all data?

Most of the values ​​in the world are corporations. Everything that happens in corporations, is based on contracts. I would not call the treaty a narrow spectrum, it is closer to the expression “all the money of the world.”
There are analysts who predict that most of the money on the blockchain will be earned in industrial blockchains.

IBM and Linux Foundation are very active in the blockchain, SAAS solutions are already being sold by Amazon, Microsoft and Red Hat. Oracle, as always, is lagging behind, but also announced a blockchain project.

There are a lot of announcements, but few realizations, of course. However, little by little the decisions on the blockchain enter into the mode of normal operation.

Blockchain is a way to replicate a database. Variable base, or not, open, or not - depends on the implementation. The emphasis on non-repudiation is done because it is very difficult to achieve this level of reliability by other means.

Speak a few words about your report .

This is a review report on the blockchain world of diversity. I will tell about
financial system, the place of cryptocurrency in it, the types of blockchain and
major trends.

Come discuss the topic on May 18th. Habrayuzerm discounts .