An overview of the development of the oracle machine project
This year, there have been many projects focusing on Oracle oracles, which gradually play a more important role in the architecture system of the blockchain as the entrance to interact with the real world and blockchain data.
Common applications such as gambling and entertainment, but the real value of oracles is in risk management and investment management in the financial industry.
The puzzle for the success of the oracle project?
- State Channels - Option to Improve Scalability
- Sharding - an option to improve scalability
- Light Nodes - Improve Availability and Security
- Marketplace on Lightning Network - Efficient Matchmaking
- An oracle that informs the blockchain of the final facts
- A base chain to carry these functions and applications
- A community with a user base
Which teams are developing oracle projects?
Amoveo, Augur, Gnosis, Aeternity, Zen Protocol, Bitshares, STOX, Bodhi and Bitcoin Hivemind to name a few.
1*Status channel
Hivemind's idea of applying Lightning Network This is Hivemind's application solution. Compared with the standard Lightning Network solution, it can be broken down in detail next time.
There is no information published by Gnosis or Augur about state channels, but they both claim to use state channels.
The Amoveo state channel has been tested and all users can try out the Amoveo state channel by installing the erlang full node and using the web browser interface.
Aeternity has updated the white paper and has not uploaded the code related to the state channel. According to the white paper, Aeternity will have a full state channel capable of running off-chain smart contracts.
The content of state channels is not included in the stox, Bodhi white papers.
2* Shard
Introduction to Amoveo Sharding This is a document explaining how Amoveo sharding works. Simply put, because Amoveo is a stateless smart contract system, since no contract state is stored on the blockchain, it can simply be divided into several channels and partial merkle trees to execute and verify state sharding.
Gnosis, Stox and Augur are all based on the Ethereum platform, and the current version of Ethereum does not yet have the function of sharding.
Bodhi is based on QTUM, and its upper layer is derived from EVM, which also lacks the sharding function.
Bitcoin Hivemind reuses the Bitcoin source code, and obviously, does not have the function of sharding.
zen Protocol, Aeternity and Bitshares have no plans to support sharding.
3*Light Node
Amoveo can use the light node wallet link in the browser . Amoveo miners can use only light nodes without relying on the full ledger, and the entire network can be all light nodes.
Gnosis, Stox and Augur are based on Ethereum, which can provide a light node model, but there is a weakness here, in the worst case, the Ethereum light node must replace all the functions of the full node, but the light node does not store all the state , so that light nodes can only strike.
QTUM, which Bodhi is based on, also provides light nodes, but since QTUM uses UTXO instead of an account model, QTUM has the same limitations as Bitcoin. If a light node wants to query the full balance, it needs to prove to the light node by scanning the entire UTXO set by the full node. Obviously, the overhead of finding balances triggered by micropayments is significant.
None of the other projects have light nodes or have plans to use them.
4* Trading Market
Projects including Bitshares, zen protocol, Stox, Bodhi, and Aeternity put trading markets on-chain. The disadvantage of on-chain markets is that they cannot be scaled through state channels.
Hivemind, Gnosis, and Augur put the market off-chain, but they use a broker model, which is much less efficient than an order system.
It seems that Off-chain's order system model is the most efficient solution.
5* Oracle
The Oracle mechanism of most projects cannot be upgraded, and some use less secure mechanisms, such as vote-based or external data sources.
Unupgradable oracles are too expensive or sometimes ineffective. Assuming that the amount bet on the oracle is much larger than the amount in the oracle mechanism, in order for the oracle to be useful, we need to be able to provide accurate data about the outside world. In order for an oracle to function effectively under these conditions, users need to submit more collateral to the oracle to make it more secure, which can be achieved by upgrading to make the stake more valuable.
Stox中创造预言机的人需要提供抵押品即担保物。整个预测过程，担保金额不会发生变化，同时，投注量受到预言机创建者提供的担保金额的限制。 Stox的预言机无法升级
Aeternity 和Bodhi使用外部可靠数据源，不依赖抵押品，这样会很容易受到操控和匿名攻击。
Augur以REP代币作为抵押品，抵押品的数额即REP的价值。 Augur预言机保证所有市场下注量受到REP市值的限制，其中包括那些链外的交易。 Augur也不能升级。
Gnosis对于其预言机升级机制的解释见 链接。“终极预言机”是升级的一部分，它的solidity实现在github仓库Gnosis 预言机
Amoveo预言机可以升级，测试代码
6*基础链平台
Gnosis，Stox和Augur使用以太坊作为基础链，它是典型的二代区块链系统
菩提使用QTUM，目前已上线主网。
Bitshares自己就是基础链平台，预言机只是其上的应用。
Amoveo，Bitcoin Hivemind和Zen Protocol都上线了测试网络，可以试用来构建服务。
Aeternity还没有测试网。
原文地址： https://zhuanlan.zhihu.com/p/31447124