On August 12, 2020, IPFS officially released its latest blog, focusing on the unique features of the Filecoin network. Filecoin will become the first well-known user to produce the drand network, and Starworld will translate it for everyone at the first time. Next, we will discuss in depth what drand is and how it works.
This month, an alliance of organizations dedicated to providing a publicly verifiable, unbiased source of randomness as the organization's basic Internet service is upgrading to a production-level service, which will be used as Filecoin's off-chain source of randomness. In the future, Drand can provide a reliable and fair source of randomness for many blockchain systems and applications.
Why is randomness important?
The results produced by a random system have a uniform probability distribution and are randomly independent of each other. We encounter randomness every time we roll a dice and coin: when you roll a fair coin, the probability of heads and tails is the same or the same (evenly distributed), and you cannot predict any single one based on past results The result of the coin toss (random independence).
However, randomness can be used not only to determine the statistics of coin toss and dice toss. In fact, we rely on randomness in everything from encryption and network security to election audits and online gambling.
That's because randomness makes certain digital processes resistant to manipulation. To give just one example, any cryptographically secure system can resist fraud and hacker attacks only if the cryptographic keys it uses are incredible. Moreover, it is difficult to guess the key only if the source value used to generate the key is appropriately random. In other words, the basis of secure encryption is randomness.
However, not all randomness is equal. For example, when generating a random integer between 1 and 10, you should have a one-tenth chance of guessing it correctly. However, if your randomness generator exhibits bias or patterns, the chance of guessing the integer correctly may be greater than one in ten. In other words, a key issue is the use of "predictable" generators. Predictable randomness once again opens the door to fraud and hacking. We not only need randomness, but also good randomness. Good randomness is harder than you think.
The quality of randomness is measured by its unpredictability, which is a kind of randomness called "entropy". Since computers are deterministic systems, it is algorithmically impossible to use computer algorithms to create true high-entropy randomness.
However, even if physical randomness is generated by a single source, it is easy to bias. If you can control, manipulate, or otherwise influence the source of randomness, then you can be biased towards the obvious random result to your advantage, such as the recent high-profile lottery fraud case that is clearly revealed. For many random use cases, such as election review and encryption, you also need randomness to be publicly verified. The random number generator only has a way to communicate to the user. If you cannot verify that the received number is actually random, your system may be attacked and manipulated.
It is difficult to find good randomness, that is, high entropy, resistance to bias and publicly verifiable. For many years, no service can generate such randomness on a large scale. But there is a new project that can complete the task. It is called drand (short for distributed randomness) and it is what Filecoin uses as its source of randomness.
What is drand?
drand is a so-called random beacon, which is a service that provides publicly accessible randomness for use by third parties. Although random beacons have been around for some time, drand is unique in that it generates randomness by combining the contributions of a network of independently operating servers. This means that drand incorporates the strength, security and resilience of distributed networks into the randomness generation process. In many ways, this makes drand the industry's number one random as a service.
Drand's open source software is a global network that runs on the Entropy League, which is maintained by a group of different organizations, including the maintenance protocol laboratory, along with C4DT, ChainSafe, cLabs, CloudFlare, Emerald Onion, EPFLDEDIS, and Revenge Fund Yes, IC3, Kudelski Security, PTisp, University of Chile, Tierion and UCL. Because the drand network is distributed across multiple server nodes, there is no central point of failure, which means drand is not subject to prejudice and cannot be prevented by the destruction of a single insider or a single network partner. Moreover, as an open source project, drand is directly supported by its users, thus ensuring that the protocol is always an evolving project that can meet the needs of its community.
The main function of drand is to generate publicly available randomness for everyone to use. In order to perform this function reliably, all nodes in the drand network collaborate to generate randomness at regular intervals (called "rounds").
In each round of randomness generation, drand provides three different attributes for randomness: unpredictability, unbiasability and verifiability. This means that each round of random generation (1) cannot be predicted by any party participating in the random generation process, (2) is uniformly random and unbiased, and (3) can be verified as truly random by verifying a single signature.
Drand provides the most reliable, high-entropy public randomness to date. This is why we use the randomness generated by drand in the Filecoin network. V丨ipfssy
How Filecoin uses drand
Many cryptocurrencies and blockchain-based networks require good randomness to operate safely and effectively, and Filecoin is no exception. Filecoin relies on good randomness values to maintain "liveness" or to maintain all customers' consensus on the correct history of the Filecoin blockchain. That's because Filecoin uses randomness to perform leader elections to determine which miner will release a new block to the blockchain.
Leader election is the way the Filecoin blockchain grows. The blocks in the Filecoin blockchain are arranged by era, and each era may elect multiple leaders. In the leader election, at least one miner is selected from a group of miners, and these miners are weighted according to the storage capacity that these miners contribute to the Filecoin network. The selected miners start a new era by generating the next block on the blockchain and receiving rewards for that block.
The leader election records the history of the Filecoin blockchain, so it is important that the process of electing leaders cannot be tampered with, is fair, unpredictable and fair. In order to ensure that this election is fair and equitable, Filecoin needs good randomness. At the same time, Filecoin needs that the randomness it uses can be publicly verified, because the elected leaders need some way to prove to other miners that they are actually elected.
Drand accurately provides the high-entropy, unbiased and publicly verifiable randomness value that Filecoin needs for the fairness and security of its leader election. Its unique function ensures that Filecoin's leader election has the same fault tolerance as drand and is not affected by prejudice and confrontational manipulation. Using drand as the source of randomness values, the Filecoin network can guarantee activity.
drand's future
Drand is a fast-growing project with plenty of room for growth. With the development of drand, we may see the expansion of the network in new ways to meet the growing industry needs and adapt to new technologies, such as advances in cryptography and quantum computing. But drand is already a cutting-edge service that can make important contributions to many digital projects including the Filecoin network.
Interplanetary Infinity is the original creator of fog storage and fog computing in the future, a leading IPFS ecological builder in the country, and an innovative company focusing on IPFS technology research and development, distributed storage software and hardware development, and blockchain ecological construction. The current main business includes Fog computing and fog storage technology development, IPFS underlying research, distributed storage server development, trading platform and digital wallet development, and high-tech industries such as the Internet of Things and 5G applications.