Tag Archives: introduction

Blockchain introduction – Michał Staśkiewicz

hello everyone today I wanna share with you some knowledge about the blockchain just some basic level because this is really complex thing and I don't want to go deeper into the technical solution just the overview about the blockchain so first I want to talk something about the basic concept about that whole blockchain and then I want to talk something about the problems that blockchain try to solve because blockchain like every other technology is created for solving the kind of problem and then I just want to give you overview about mining and what exactly is it why we need it ok so first the blockchain isn't a Bitcoin because this is the most over hyped keyword in the internet and this is it isn't true because the blockchain is the technology behind the Bitcoin and any other cryptocurrencies and much much more spoiler ok so this is the definition of the blockchain is distributed continues growing list of Records called blocks which are listed and etc so basically it's a distributed data store something like linked items but first we need to think about what does it mean the system is distributed and there is the imagination what is the difference because between centralized decentralized and distributed in this images we can see that centralized have single point of failure so if one place of our system will be down everything will be crushed etc but it has also the strength with the pros because if we have everything in central place it's easy to maintain and decentralized systems are much more complex than centralized because we have few points that working concurrently and distributed it's even more far because every node of our system can connect with each of the neighbors so the whole system if we one node is broken we can easily replace it with another and another so it's really fault tolerant but also it's much harder to maintain ok so this is the core problems that blockchain wants to solve it's a short list but it's really we can use blockchain for almost everything like data store but I think it's designed to better implement the banking, assets exchange and distributed market because this is the most painful part of the exchanging and etc we need providers etc with blockchain we can do everything by ourselves so it much simplifies the full process ok and we can now imagine the problem that we have two person one in Canada and another in Australia Sydney and the problem is that one person want to send another person one thousand dollars and okay so person A can go to the bank and send the money to person B and in classic Banking we need the trusted third party so it's the provider that will process our transaction and move money from place A to place B so person A can send $1,000 to the third party and it takes a long time even a few days that the third party will process it and then person B get the money but like you can see the third party takes on fees and it takes time it takes fees so it's not the efficient way to moving this money but now let's move this problem to the blockchain and how the blockchain can help us solve this problem and in other way and much faster and cheaper but before that we need to think what is the open ledger concept in the blockchain ledger is something like data store with blocks and every one block is connected with previous one block the only the first block is the exception because the first block always is hard-coded in the source code because we cannot calculate the key to before the something before because the block is the first and every one block with some records is connected to the previous one with the key it's some cryptographic algorithm that take much much computation power because it's just guessing the key for the previous block and it's forming something like chain so our ledger is a chain of records every next record is connectedwith the previous one something is broken okay so now we can see that we have four person and every one of those person have some account on the blockchain of his wallet or something and now we've person Peter want to send, we can see that he have $100 and he want to send the money to the Ann so he just published the transaction and he like you can see it's next block connected with the previous one that defined he have the money the next if Ann want to send the money we can easily check okay he have already $40 so he can send easy the money like you can see Steve also can publish the block and save the money to the Dave it just like giving money from hand to hand then we can see this is a open ledger but in practical world it looks totally different but this is the concept image of this every ledger have a few items that's building the block first of this is the block every one block every record is a block and every block also have their own ID and the reference to the previous block that is like a previous set that is computed by hashing power and it cost a lot and the every block has the content with the transactions or even other data because for today we have also blockchain that are storing files websites computing power etc

so basically we can store there everything okay so on the second or third slide I've presented that the blockchain is distributed so we don't have this ledger in the central part of our system it's distributed every of the user have the own copy of that chain that we have on the central part so everyone exactly knows what amount of money have everyone else okay but what if one of the people wants to fraud each other so like you can see the Peter have $100 and transfer the $30 to Ann and then he want to send $500 to Dave but like you can see everyone knows that he don't have this money so he can't trick them because everyone knows that he don't have this money and system automatically will know that okay so what are you doing you don't have this money and the transaction will be just moved to trash because it's invalid so it's really fraud resistant and transparent also it's building new way of we trust each other because if if you know that everyone knows everything so you can't trick them it's just just simple and what is the mining mining is the process that we need to connect the next block to the previous one and it's expensive in computation power because is just guessing we cannot just calculate it we need guess guess guess and get the result so imagine that the Ann want sent money to Dave so what he needs to do the first thing the concept of miners every user of the chain can be the miner miner is the person who gives the computation power to solve these blocks like I said before this key we need computate and everyone can be the miner miners can compete with each other because the miner who first solve the problem will get the reward because every next block have the reward for the miner so then we think that about the Ann want to send the money to Dave so first she needs to publish the transaction so ok I want send you $10 but this transaction is unconfirmed because we we don't know where we want to pin this transaction we don't know where is that block before so we need to calculate it and create this link the key reference for the two blocks and the miners are competed with we will see that okay there is now a new unconfirmed block so we can take it and try to guess the key if the miner gets the key then the block is confirmed because everyone now know how to link this block to the blockchain that is stored in the everyone computer and after the solving it's so broken and after confirmation the miner who will win the competition take the reward exactly in Bitcoin it's 75 Bitcoin per one confirmed transaction so it's a lot but it also need a huge amount of computation power and after the confirmation everyone now knows where to pin the block to their copy of the blockchain so the miner broadcast the information through the full network so everyone pinned the transaction and everyone know now the Ann don't have $10 because she move it to Dave and that's all the basic of the blockchain is just linking the container blocks one to another any questions [so I have two things one is like] [for now mining bitcoins consume more power than some countries consume] [so it's pretty expensive if you think about] [and second thing is like this also takes much much longer time to compute another block] [it's like how do you see it] [If you have your own private chain] [for how long it's not a a problem the complexity grows with time] with your own block today you can choose the solution like sub block for another block like you can use at Ethereum so it's the like AWS for our development we can put there our sub block and hashing power of that Ethereum will be used to compute our blocks and for me it's not a problem by now because in the blockchain we can move asset from place A to place B in in I think less than 15 minutes but in 15 mins here even the network is really busy but in comparison the third party it takes up to three days so it's much faster [now it's like fifteen minutes] ]fifteen minutes if the network is not so busy it's like few seconds [one more thing because I am not sure if I catched it correctly] [because whenever you try to make one transaction you take the previous one] [let's say there are few people that are trying to do the same] yeah I don't get this on the presentation but there is a place where if you want to transact something the transaction is going to this box of things yeah there is a algorithm that sort these blocks by timestamp and they are distributed to the miners etc etc it's really complex thing between the publish [there is sequence of transactions a lot of transactions is part of one block] [but whenever you would like to use it for example to sign contracts stuff like this] [you probably would do it for each operation one below] [so still you need some orchestration] yeah but the network is designed in that way that blocks are sorted kind of automatically and [because this is expensive few people try the same the first will get] because it's distributed so [the other is wasted] there are also many algorithms that eliminate the collision and invalidate blocks etc because if we have [the concurrent system] we cannot and by this we don't have this central store central place but like you said this is the another problem that blockchain solving yeah software for the blockchain that the orchestrating these transactions and publishing eliminating collisions etc okay and other questions okay thanks