The bitcoin network is a peer-to-peer payment network that operates on a cryptographic protocol. Users send and receive bitcoins, the units of currency, by broadcasting digitally signed messages to the network using bitcoin cryptocurrency wallet software. Transactions are recorded into a distributed, replicated public database known as the blockchain, with consensus achieved by a proof-of-work system called mining. Satoshi Nakamoto, the designer of bitcoin claimed that design and coding of bitcoin began in 2007. The project was released in 2009 as open source software. The network requires the minimal structure to share transactions. An ad hoc decentralized network of volunteers is sufficient. Messages are broadcast on a best effort basis, and nodes can leave and rejoin the network at will. Upon reconnection, a node downloads and verifies new blocks from other nodes to complete its local copy of the blockchain. A bitcoin is defined by a sequence of digitally signed transactions that began with the bitcoin's creation, as a block reward. The owner of a bitcoin transfers it by digitally signing it over to the next owner using a bitcoin transaction, much like endorsing a traditional bank check. A payee can examine each previous transaction to verify the chain of ownership. Unlike traditional check endorsements, bitcoin transactions are irreversible, which eliminates the risk of chargeback fraud. Although it is possible to handle bitcoins individually, it would be unwieldy to require a separate transaction for every bitcoin in a transaction. Transactions are therefore allowed to contain multiple inputs and outputs, allowing bitcoins to be split and combined. Common transactions will have either a single input from a larger previous transaction or multiple inputs combining smaller amounts, and one or two outputs: one for the payment, and one returning the change, if any, to the sender. Any difference between the total input and output amounts of a transaction goes to miners as a transaction fee. In 2013, Mark Gimein estimated electricity consumption to be about 40.9 megawatts (982 megawatt-hours a day). In 2014, Hass McCook estimated 80.7 megawatts (80,666 kW). As of 2015, The Economist estimated that even if all miners used modern facilities, the combined electricity consumption would be 166.7 megawatts (1.46 terawatt-hours per year). To lower the costs, bitcoin miners have set up in places like Iceland where geothermal energy is cheap and cooling Arctic air is free. Chinese bitcoin miners are known to use hydroelectric power in Tibet to reduce electricity costs. Various potential attacks on the bitcoin network and its use as a payment system, real or theoretical, have been considered. The bitcoin protocol includes several features that protect it against some of those attacks, such as unauthorized spending, double spending, forging bitcoins, and tampering with the blockchain. Other attacks, such as theft of private keys, require due care by users.
Golem is a decentralized supercomputer that is accessible by anyone. The system is made up of the combined power of user’s machines from personal PCs to entire datacenters. Golem is able to compute almost any tasks from CGI rendering through machine learning to scientific learning. It utilizes an ethereum-based transaction system to clear payments between providers, requestors and software developers however it is safe because all computations take place in sandbox environments and are fully isolated from the hosts’ systems. The company released Brass in 2016 which includes Blender and LuxRender which are the two tools for CGI rendering. There are three releases that follows which are Clay, Stone and Iron. Golem has recently updated their Brass Beta and the highlight of this upgrade are the streamlined task creation GUI, the support for partial task restart in case of subtask timeouts and the fix that should alleviate the issues with the Docker service on Windows. Other than that, improvements have been made on the Blender verification and transaction tracking subsystems and fixed some minor pain-points in the UX. Transaction history will become more user-friendly with separate tabs for payments and incomes. Apart from that, improvements are made for requestors as well, requestors is now able to add resource file without having to repeat the task creation procedure if they have forgotten to add them beforehand. Grand vision and core features ● Golem is the first truly decentralized supercomputer, creating a global market for computing power. Combined with flexible tools to aid developers in securely distributing and monetizing their software, Golem altogether changes the way compute tasks are organized and executed. By powering decentralized microservices and asynchronous task execution, Golem is set to become a key building block for future Internet service providers and software development. And, by substantially lowering the price of computations, complex applications such as CGI rendering, scientific calculation, and machine learning become more accessible to everyone. ● Golem connects computers in a peer-to-peer network, enabling both application owners and individual users ('requestors') to rent resources of other users’ ('providers') machines. These resources can be used to complete tasks requiring any amount of computation time and capacity. Today, such resources are supplied by centralized cloud providers which, are constrained by closed networks, proprietary payment systems, and hard-coded provisioning operations. Also core to Golem’s built-in feature set is a dedicated Ethereum-based transaction system, which enables direct payments between requestors, providers, and software developers. ● The function of Golem as the backbone of a decentralized market for computing power can be considered both Infrastructure-as-a-Service (IaaS), as well as Platform-as-a-Service (PaaS). However, Golem reveals its true potential by adding dedicated software integrations to the equation. Any interested party is free to create and deploy software to the Golem network by publishing it to the Application Registry. Together with the Transaction Framework, developers can also extend and customize the payment mechanism resulting in unique mechanisms for monetizing software. Check out CoinBureau for the full review of Golem.