什么是以太坊GAS

理解以太坊一定要理解以太坊中的gas的概念,以太坊gas可以说是以太坊生态系统的命脉

任何涉及到以太坊的行为,无论是简单交易,还是智能合约,甚至ICO都需要一定量的gas。gas是衡量执行某些操作所需的计算量的单位,用来计算为了执行操作而需要支付给网络的费用数额。

这里我们将了解gas的工作原理和具体对gas的具体理解。

1.什么是以太坊gas

gas的名字起得非常贴切,翻译成中文就是天然气的意思。在这之前,我们先了解下bitcoin的背景和bitcoin面临的问题。

比特币的创建是因为每个人都在问同样的问题:

• 是否有可能创造一种可以在没有任何中间人的情况下在两个人之间转移的金钱形式?

• 是否有可能创建一个可以在区块链等功能上运行的分散化资金?

Satoshi Nakamoto在创造比特币时回答了这些问题。我们终于有了一个去中心化的货币体系,可以将资金从一个人转移到另一个人身上。

然而,比特币存在问题,这是所有第一代区块链都存在的问题他们只允许货币交易,没有办法为这些交易添加条件。

Alice可以发送Bob 5 BTC,但她不能对这些交易施加条件。例如。她不能告诉鲍勃,只有当他执行某些任务时他才能拿到钱。

这些条件将需要非常复杂的脚本,需要一种“东西”使流程更加无缝。…这个“东西”是就是以太坊的智能合约。关于以太坊的基本原理不多阐述,各位可以参考:区块链技术:以太坊系统核心总结

进入正题:

2.什么是以太坊gas?

正如介绍中所解释的那样,Gas是一个单位,用于测量执行某些操作所需的计算量。

以太坊虚拟机(EVM)中运行的所有智能合约都使用 solidity进行编码(以太坊计划未来将从Solidity转移到Viper。)每一行代码都需要一定量的gas来计算,就好比汽车要用汽油。

下面的图片来自以太坊黄页,可以用来粗略地了解多少具体说明的成本。

图片来源:Ethereum Yellow Paper

3. 以太坊Gas如何工作

为了更好地理解以太坊的gas工作方式,我们使用一个类比。假设你正在进行一次公路旅行。在你这样做之前,你要经过这些步骤:

• 你去加油站,并指定你想要在你的车中注满多少汽油(gas)。

• 你的汽车里充满了汽油(gas)。

• 你向加油站支付你欠他们汽油(gas)的金额。

现在,让我们来与以太坊展开类似的比较。

汽车,就是你想要执行的操作,如gas或智能合同。

加油站是你的矿工。

你付给他们的钱是矿工费。

用户希望在以太坊执行的所有操作必须为以下方面提供gas:

• 涵盖其数据,即intrinsic gas。

• 覆盖整个计算。

现在我们已经介绍了基本的基础知识,你可能会问以下问题。

为什么我们有这个gas系统?

答案很简单…激励

像任何工作对等系统一样,以太坊严重依赖矿工的哈希效率:更多的矿工,更多的哈希效率,更安全和快速的系统。

为了吸引更多的矿工进入该系统,他们需要使该系统对矿工有利可图并尽可能诱人。在以太坊,矿工有两种赚钱方式:

• 通过挖掘块和获得块奖励。

• 通过成为他们的开采块裁决和打包者。

我们来探讨第二点。

矿工负责将交易置于其区块内。为了这样做,他们必须使用他们的计算能力来验证智能合约。gas系统允许他们为此收取一定的费用。

这笔费用被称为矿工费,它有助于激励他们积极参与生态系统。

那么,他们可以收取多少费用?

gas度量的最小单位是wei。所以,如果我们在操作过程中花费1个gas单位,我们称它为1 wei。

单位增加如下:

那么:

4:我们如何将gas转换成以太?

没有固定的转换价格,完全取决于矿工来确定转换价格,然而,平均转换率通常为:1 gas = 0.02 micro Ether

如果要继续深入,了解Gas Limit的概念很重要:

5:以太坊燃料限制(Gas Limit)是什么?

为了在Ethereum中完成操作,发起交易的人员或智能合约创建者必须在向矿工提交Gas Limit之前指定Gas Limit。当指定Gas Limit时,矿工将开始执行操作。

提交Gas Limit时,必须考虑以下几点:

• 不同的运营会产生不同的gas成本(如前所示)。

• gas用完时,矿工将停止执行。

• 如果有剩余gas,将立即退还给发起交易的人员或智能合约创建者。

让我们在假设的场景中看到这一点。

假设我们添加两个数字,并且合同必须执行以下操作:

• 把10存储在一个变量中 —假设这个操作成本是45 wei 的gas。

• 储存最终结果 —成本为45wei。是10 wei。

• 储存最终结果—成本为45wei。

假设 gas limit是120 wei。

矿工使用的gas总量为45 + 10 + 45=100 wei。

假设1 wei的费用为0.02 micro ETH,则所欠的费用为(100 * 0.02 micro ETH)= 0.000002 ETH。

现在,剩下多少gas?

120 – 100 = 20 wei。

20 wei退还给发起交易的人员或智能合约创建者。

所以,在指定的情况下,我们必须考虑两种情况:

• gas limit太低。

• gas limit太高。

情景#1:gas限制太低

如果一个操作用尽了gas,那么它就会恢复到原来的状态,就好比啥事都没发生过,然而,发起交易者或智能合约创建者仍然需要向矿工支付计算成本的费用,并将操作添加到区块链中(即使它尚未执行)。

回到我们的刚刚提到驾车旅行的比喻,如果你的汽车中没有充足的汽油,那么你将无法到达目的地,但即使如此,你还是向加油站支付了燃油费。

让我们看看这是如何在我们假设的智能合约中起作用的。步骤是:

• 把10存储在一个变量中—假设这个操作成本是45 wei 的gas。

• 增加两个变量—假设这个成本是10 wei。

• 储存最终结果—成本为45wei。

但是,这一次,gas limit是90wei

现在,我们知道履行合同所需的gas是100 wei,但我们却有90 wei的限制。

在这种情况下,矿工将进行90 wei的计算,然后对90 wei的运行生成器费用进行计费,结果为(90 * 0.02微ETH)0.000018 ETH。

此外,合约还原为原始状态并添加到区块链中。

情景#2:gas limit太高

那么,如果我们将gas limit设置得太高怎么办?

是不是看起来很合理?毕竟剩下的东西都退还给发起者是吧?

虽然听起来不错,但在现实中并没有那么好。

矿工受到每块6,700,000gas limit的限制。以太坊的每个简单交易通常都有2.1万的gas limit。矿工只能增加加起来小于或等于块gas limit的操作。

图片来源:Hackernoon

假设有一个交易A有一个42,000 gas limit 和两个交易B和C的正常 limit (如21,000)。

哪一个矿工更容易投入其中?

• 他们是否会优先进行交易A并退还大量gas?

• 或者他们会优先处理交易B和C并且退还少量gas?

显而易见,第二点对他们来说更具备吸引力

这正是为什么超高的gas limit不是明智的做法。

以下是平均gas限制图表。

图片来源:Hackernoon

到目前为止,你应该清楚,gas和以太币不是一回事,就如燃料(gas)和费用(fee)不是同一回事一般。gas是需要的计算能力的数量,而以太币是价格,也就是人们必须为这种gas支付的费用。

现在我们已经掌握了迄今为止所获得的一切,让我们通过一些gas和收费情景。

如果一项操作只有低gas,那么矿工不会去处理,因为它没有足够的gas来完成计算。

如果一项操作的费率(fee)较低,但矿工们仍然不会去处理,因为低费用的工作没有吸引力。

如果一个操作有高gas,那么这意味着gas limit非常高,矿工还是不会去处理。

如果一项操作收取高额费用(fee),那么矿工知道他们会从中赚取很多钱,当然优先处理。

根据ethgasstation推荐的不同交易费用的gas价格是:

以太坊gas机制。它是否合理?

尽管gas系统因为提出了一个能够非常积极地激励矿工的平稳运行机制而受到赞扬,但最近也受到了很多质疑,因为对于开发商和智能合约创造者来说成本有点高了。无论如何,以太坊项目的参与者必须了解这些成本,并据此设计 dApp 。我们需要在区块链链上和链外的复杂性之间找到平衡。

By 刘杨

Decentraland – A Virtual Reality Platform

Decentraland is an Ethereum-powered virtual reality platform. In this virtual world, you purchase plots of land that you can later traverse, build upon, and monetize. There’s no limit to what you can do. It’s the first digital platform that’s completely owned by its users.

In this Decentraland beginner’s guide, we’ll dig into:

How Does Decentraland Work?

Similar to games like Skyrim and Fallout, Decentraland is an all-immersive virtual universe. However, instead of playing on a two-dimensional screen, you participate in a three-dimensional world. It seems to be the logical next step before creating full-blown AI-based games in the physical space, à la Westworld.

What Is LAND?

In Decentraland, the spaces that you interact with are LAND, non-fungible digital assets that you purchase in the game. Once you own a plot of LAND, you’re free to do with it as you choose. You can create games, applications, gambling services, or even dynamic 3D scenes. But, why stop there? Although not its primary purpose, you can also create LAND-based services around education, professional development, tourism, etc.

The number of LAND is capped, and each plot of LAND is 33 feet by 33 feet, but there’s no limit to its height. Recently Decentraland created LAND Estates, a feature that allows you to more easily manage your LAND by associating adjacent plots. If you’re interested in purchasing LAND (or just want to see the map), you should check out the LAND marketplace.

Similar groupings on LAND comprise Districts. Districts are basically communities that revolve around a shared theme. For example, there may be a District just for crypto enthusiasts with cryptocurrency apps and services. You can vote on District issues through Decentraland’s voting dApp, Agora. The amount of LAND you hold in a specific district correlates to the weight of your vote. Decentraland created Agora to give you more control over what happens in your districts, and to provide feedback on the platform at large. 

What Is MANA?

MANA is Decentraland’s cryptocurrency token. It’s an ERC20 token that you use to purchase plots of LAND as well as pay for in-world goods and services.

When you buy LAND, Decentraland burns the MANA that you purchase it with. The Decentraland team originally sold each plot of LAND for 1000 MANA. Now that there’s a secondary market, though, the LAND prices vary. Currently, the cheapest plot of LAND is 11,750 MANA while more popular areas have price tags in the millions. The highest selling plot went for 2,000,000 MANA, or $175,578, in March 2018. This was quite a bit of money for a virtual plot of land and left the seller with a nice profit.

Technology Architecture

Decentraland’s protocol has three layers:

  • Consensus layer: Tracks land ownership and land content through an Ethereum smart contract.
  • Land content layer: Uses a decentralized distribution system to render the content in the virtual world.
  • Real-time layer: Provides peer-to-peer connections for users to interact with one another.

The team is building the virtual reality platform using A-Frame. To build in the world, you can first create a model in SketchUp and/or Blender, and then import it onto the platform.

Decentraland Team & Progress

The Decentraland team is led by Ari Meilich (Project Lead) and Esteban Ordano (Tech Lead). Ordano previously worked at Bitpay as a software engineer and founded Smart Contract Solutions, Inc. Both founders have also worked together in creating Stremium and Bitcore.

decentraland founders

Decentraland has been around for longer than you may think. The team hit their first development milestone, Stone Age, in June 2015. This was a simple, pixelated grid that allocated pixels to users through a proof-of-work algorithm. Most recently, they held a Terraform Event in which they sold LAND in the new, 3D world.https://267db645734dd440dbc53370a2db3c85.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.htmlThe team has also partnered with district0xAragon, and imToken to provide some of their services.

Decentraland is fairly unique in the blockchain world with no large, direct competitors. High Fidelity and Sansar both provide spaces to create and sell virtual reality experiences, but they aren’t blockchain based. MARK.SPACE seems to be the most similar project; however, it’s far behind Decentraland in both development and notoriety.

Trading

The MANA price was relatively stagnant until the December/early-January market explosion. Since then, the coin has done relatively well compared to the rest of the altcoin market, maintaining about 75% of its Bitcoin value in the subsequent downturn.

MANA hit its all time high in January 2018 at $0.26, hitting two more peaks in May and July, $0.18 and $0.14 respectively. Since July 2018 MANA has continued to fall, reflecting the trends of the crypto markets.https://267db645734dd440dbc53370a2db3c85.safeframe.googlesyndication.com/safeframe/1-0-38/html/container.html

Because the only use for MANA, right now, is to purchase LAND, it’s hard to predict what will affect the price. An increase in demand for LAND may only lead to a rise in the amount of MANA you need to purchase some – not a rise in the MANA value itself. The MANA price should increase, though, as you become able to buy more things with it.

Where to Buy MANA

You can purchase MANA on most major exchanges with either Bitcoin or Ethereum. Binance and OKEx have the largest trading volume of the exchanges.

If you don’t own either of those two coins, and you’re confused where to start, check out our Bitcoin buying guide or Ethereum buying guide.

Where to Store MANA

MANA is an ERC20 token, so there are numerous wallet options for you to choose from. We recommend using a hardware wallet like the Trezor or Ledger Nano S. These keep your funds offline and are less susceptible to malicious software.

MyEtherWallet is another popular option if you’re not looking to spend the money on a hardware wallet.

Conclusion

Decentraland is a virtual reality platform that you can purchase land on. Tapping into the imagination of gamers and entrepreneurs everywhere, you’re able to do whatever you want with the land that you purchase.

This is a unique project in a largely untested market. The popularity of “alternative life” games is a good sign, but it’s hard to tell if this will carry over into the 3D and blockchain space. However, if Decentraland gains the adoption that its supporters hope it will, then we may just see an entirely new ecosystem of businesses and experiences flourish before our eyes.

By Steven Buchko

Ethereum Gas Fully Explained

  1. Ethereum Gas is a unit that measures the amount of computational effort that it will take to execute certain operations.
  2. Every single operation that takes part in Ethereum, be it a transaction or smart contract execution requires some amount of gas.
  3. Miners get paid an amount in Ether which is equivalent to the total amount of gas it took them to execute a complete operation.

Ethereum Gas – is the lifeblood of the Ethereum ecosystem, there is no other way of putting that. Gas is a unit that measures the amount of computational effort that it will take to execute certain operations.

Every single operation that takes part in Ethereum, be it a simple transaction, or a smart contract, or even an ICO takes some amount of gas. Gas is what is used to calculate the amount of fees that need to be paid to the network in order to execute an operation.

In this guide, we are going to understand how gas works. But before we do so, there are several concepts that we must learn. So, without further ado, let’s begin our deep dive on Ethereum Gas.

What is Ethereum Gas: Step-By-Step Guide

Why is gas not needed in Bitcoin?

Bitcoin was created because everyone was asking the same questions.

  • Will it be possible to create a form of money which can be transferred between two people without any middleman?
  • Will it be possible to create a decentralized money which can function on something like the blockchain?

Satoshi Nakamoto answered these questions when he created bitcoin. We finally had a decentralized monetary system which can transfer money from one person to another.

However, there was a problem with bitcoin which is a problem with all first-generation blockchains. They only allowed for monetary transactions, there was no way to add conditions to those transactions.

Alice can send Bob 5 BTC, but she couldn’t impose conditions on those transactions. Eg. She couldn’t tell Bob that he will get the money only if he performed certain tasks.

These conditions would need extremely complicated scripting. Something was required to make the process more seamless.

…And that “something” was a smart contract.

What is a smart contract?

Smart contracts help you exchange money, property, shares, or anything of value in a transparent, conflict-free way while avoiding the services of a middleman.

What is Ethereum Gas: Step-By-Step Guide

Vitalik Buterin’s Ethereum is easily the stalwart of this generation. They showed the world how the blockchain can evolve from a simple payment mechanism to something far more meaningful and powerful.

So, what are these “smart contracts” and what’s the big deal?

Smart contracts are automated contracts. They are self-executing with specific instructions written in its code which get executed when certain conditions are made.

What is Ethereum Gas: Step-By-Step Guide

You can learn more about smart contracts in our in-depth guide here.

Smart contracts are how things get done in the Ethereum ecosystem. When someone wants to get a particular task done in Ethereum they initiate a smart contract with one or more people.

Smart contracts are a series of instructions, written using the programming language “solidity”, which works on the basis of the IFTTT logic aka the IF-THIS-THEN-THAT logic. Basically, if the first set of instructions are done then execute the next function and after that the next and keep on repeating until you reach the end of the contract.

The best way to understand that is by imagining a vending machine. Each and every step that you take acts like a trigger for the next step to execute itself. It is kinda like the domino effect. So, let’s examine the steps that you will take while interacting with the vending machine:

  • Step 1: You give the vending machine some money.
  • Step 2: You punch in the button corresponding to the item that you want.
  • Step 3: The item comes out and you collect it.

Now look at all those steps and think about it. Will any of the steps work if the previous one wasn’t executed? Each and every one of those steps is directly related to the previous step. There is one more factor to think about, and it is an integral part of smart contracts. You see, in your entire interaction with the vending machine, you (the requestor) were solely working with the machine (the provider). There were absolutely no third parties involved.

So, now how would this transaction have looked like if it happened in the Ethereum network?

Suppose you just bought something from a vending machine in the Ethereum network, how will the steps look like then?

Step 1: You give the vending machine some money and this gets recorded by all the nodes in the Ethereum network and the transaction gets updated in the ledger.

Step 2: You punch in the button corresponding to the item that you want and record of that gets updated in the Ethereum network and ledger.

Step 3: The item comes out and you collect it and this gets recorded by all the nodes and the ledger.

Every transaction that you do through the smart contracts will get recorded and updated by the network. What this does is that it keeps everyone involved with the contract accountable for their actions. It takes away human malice by making every action taken visible to the entire network

What is the Ethereum Virtual Machine?

Before we understand what the Ethereum Virtual Machine (EVM) is, we must understand why a “Virtual Machine” is needed.

So let’s go back to smart contracts.

What are the desirable properties that we want in our smart contract?

Anything that runs on a blockchain needs to be immutable and must have the ability to run through multiple nodes without compromising on its integrity. As a result of which, smart contract functionality needs to be three things:

  • Deterministic.
  • Terminable.
  • Isolated.

Feature #1: Deterministic

A program is deterministic if it gives the same output to a given input every single time. Eg. If 3+1 = 4 then 3+1 will ALWAYS be 4 (assuming the same base). So when a program gives the same output to the same set of inputs in different computers, the program is called deterministic.

There are various moments when a program can act in an un-deterministic manner:

  • Calling un-deterministic system functions: When a programmer calls an un-deterministic function in their program.
  • Un-deterministic data resources: If a program acquires data during runtime and that data source is un-deterministic then the program becomes un-deterministic. Eg. Suppose a program that acquires the top 10 google searches of a particular query. The list may keep changing.
  • Dynamic Calls: When a program calls the second program it is called dynamic calling. Since the call target is determined only during execution, it is un-deterministic in nature.

Feature #2: Terminable

In mathematical logic, we have an error called “halting problem”. Basically, it states that there is an inability to know whether or not a given program can execute its function in a time limit. In 1936, Alan Turing deduced, using Cantor’s Diagonal Problem, that there is no way to know whether a given program can finish in a time limit or not.

This is obviously a problem with smart contracts because, contracts by definition, must be capable of termination in a given time limit. There are some measures taken to ensure that there is a way to externally “kill” the contract and to not enter into an endless loop which will drain resources:

  • Turing Incompleteness: A Turing Incomplete blockchain will have limited functionality and not be capable of making jumps and/or loops. Hence they can’t enter an endless loop.
  • Step and Fee Meter: A program can simply keep track of the number “steps” it has taken, i.e. the number of instructions it has executed, and then terminate once a particular step count has been executed. Another method is the Fee meter. Here the contracts are executed with a pre-paid fee. Every instruction execution requires a particular amount of fee. If the fee spent exceeds the pre-paid fee then the contract is terminated.
  • Timer: Here a pre-determined timer is kept. If the contract execution exceeds the time-limit then it is externally aborted.

Feature #3: Isolated

In a blockchain, anyone and everyone can upload a smart contract. However, because of this the contracts may, knowingly and unknowingly contain virus and bugs.

If the contract is not isolated, this may hamper the whole system. Hence, it is critical for a contract to be kept isolated in a sandbox to save the entire ecosystem from any negative effects.

Now that we have seen these features, it is important to know how they are executed. Usually, the smart contracts are run using one of the two systems:

  • Virtual Machines: Ethereum uses this.
  • Docker: Fabric uses this.

Let’s compare these two and determine which makes for a better ecosystem. For simplicity’s sake, we are going to compare Ethereum (Virtual Machine) to Fabric (Docker).

What is Ethereum Gas: Step-By-Step Guide

So, as can be seen, Virtual Machines provide better Deterministic, terminable and isolated environment for the Smart contracts. However, dockers have one distinct advantage. They provide coding language flexibility while in a Virtual Machine (VM) like Ethereum, one needs to learn a whole new language (solidity) to create smart contracts.

The EVM is the virtual machine in which all the smart contracts function in Ethereum. It is a simple yet powerful Turing Complete 256-bit virtual machine. Turing Complete means that given the resources and memory, any program executed in the EVM can solve any problem.

What is Ethereum Gas?

As explained in the introduction, Gas is a unit that measures the amount of computational effort that it will take to execute certain operations.

Note: Before we continue, huge shoutout to Joseph Chow for his amazing presentation on Ethereum gas.

Most of the smart contracts that run in the EVM are coded using Solidity (Ethereum is planning to move on to Viper from Solidity in the future).  Each and every line of code in Solidity requires a certain amount of gas to be executed.

ETH gas price chart

The image below has been taken from the Ethereum Yellowpaper and can be used to gain a rough idea of how much specific instructions cost gas-wise. Every transaction requires at least 21,000 gas according to this table:

What is Ethereum Gas: Step-By-Step Guide

Image Courtesy: Ethereum Yellow Paper

To better understand how gas works in Ethereum, let’s use an analogy. Suppose you are going on a road trip. Before you do so you go through these steps:

  • You go to the gas station and specify how much gas you want to fill up in your car.
  • You get that gas filled up in your car.
  • You pay the gas station the amount of money you owe them for the gas.

Now, let’s draw parallels with Ethereum.

Driving the car is the operation that you want to execute, like executing a function of a smart contract.

The gas is well….gas.

The gas station is your miner.

The money that you paid them is the miner fees.

All the operations that users want to execute in ethereum must provide gas for the following:

  • To cover its data aka intrinsic gas.
  • To cover its entire computation.

Now that we have covered the bare basics, you maybe asking the following question.

Why do we have this Gas system?

The answer is simple…incentivization.

Like any proof-of-work peer-to-peer system, Ethereum is heavily dependent on the hashrate of their miners. More the miners, more the hashrate, more secure and fast the system.

In order to attract more miners into the system, they need to make the system as profitable and alluring as possible for the miners. In Ethereum, there are two ways that miners can earn money:

  • By mining blocks and getting block rewards.
  • By becoming temporary dictators of their mined blocks.

Let’s explore the second point.

The miners are responsible for putting transactions inside their blocks. In order to do so, they must use their computational power to validate smart contracts. The gas system allows them to charge a certain fee for doing so.

This fee is known as the miner’s fee and it helps incentivize them enough to take part actively in the ecosystem.

So, how much fees can they charge? Before we can calculate that let’s understand how we measure gas.

Gas is simply measured in units of gas. A transaction sent to the Ethereum network costs some discrete amount of gas (e.g. 100 gas) depending on how many EVM instructions need to be executed.

So, how do we convert the gas into Ether?

There is no fixed price of conversion. It is up to the sender of a transaction to specify any gas price they like. On the other side, it is up to the miner to verify any transactions they like (usually ones that specify the highest gas price). The average gas price is typically on the order of about 20 Gwei (or 0.00000002 ETH), but can increase during times of high network traffic as there are more transactions competing to be included in the next block.

The following chart shows you the average Ethereum gas price chart.

What is Ethereum Gas: Step-By-Step Guide

Image courtesy: Etherscan.

Before we go any further, it is important to know the concept of gas limit.

What is Ethereum Gas Limit?

In order to get an operation done in Ethereum, the sender of the transaction must specify a gas limit before they submit it to the network. The gas limit is the maximum amount of gas the sender is willing to pay for this transaction.

When specifying a gas limit, the following points must be considered:

  • Different operations will have different gas costs (as has been shown before).
  • The miners will stop executing the moment the gas runs out.
  • If there is any gas left over, it will be immediately refunded to the operation generator.

Let’s see this in operation in a hypothetical scenario.

Suppose, we are adding two numbers and for that the contract must do the following actions:

  • Storing 10 in a variable. Let’s say this operation costs 45 gas.
  • Adding two variables, let’s say this costs 10 gas.
  • Storing the result which again costs 45 gas.

Suppose the sender specifies a gas limit of 120 gas.

The total gas used by the miner to run the computation is (45+10+45) = 100 gas.

The fee that is owed to the miner, assuming 1 gas costs 20 Gwei, is (100 * 20 Gwei) = 0.000002 ETH.

Now, how much gas is left over?

120 – 100 = 20 gas.

The 20 unused gas is returned back to the sender (20 * 20 Gwei) = 0.0000004 ETH.

So, having said that, there are two scenarios that one must consider:

  • The specified gas limit is too low.
  • The specified gas limit is too high.

Scenario #1: The Gas Limit is too low

If an operation runs out of gas, then it is reverted back to its original state like nothing actually happened, however, the operation generator must STILL pay the miners the fee for their computational costs and the operation gets added to the blockchain (even if it has not been executed).

Going back to our road trip analogy, if you haven’t filled up enough gas in your car, then you will not be able to reach your destination, but even then you paid the gas station the money for the fuel right?

Let’s see how this works in our hypothetical smart contract. The steps were:

  • Storing 10 in a variable. Let’s say this operation costs 45 gas.
  • Adding two variables, let’s say this costs 10 gas.
  • Storing the result which again costs 45 gas.

However, this time, the sender sets a gas limit of 90 gas.

Now, we know that the gas that will be required for fulfilling the transaction is 100 gas, but we only specified 90 gas limit.

In this scenario, the miner will do 90 gas worth of computation and then charge the sender fees for the 90 gas which turns out to be (90 * 20 Gwei) = 0.0000018 ETH.

Also, the contract reverts back to its original state and the transaction is included in the blockchain.


Scenario #2: The Gas Limit is too high

So, what if we set the gas limit too high?

That would make sense to do right? Afterall, whatever is leftover gets refunded to the sender right?

That sounds good on paper but it doesn’t really work that well in reality.

Miners are limited by the block gas limit, which we’ll suppose is 6,700,000 gas. A basic transaction (simple transfer of ETH) has at least a gas requirement of 21,000 gas. Miners can only include transactions which add up to be less than or equal to the block gas limit.

What is Ethereum Gas: Step-By-Step Guide

Image courtesy: Hackernoon

Suppose there is a transaction A (which does a simple transfer of ETH) and has a specified gas limit of 42,000 and two transactions B and C (also simple transfers of ETH) which have specified gas limits of 21,000.

Which will make more sense for a miner to put in their block?

  • Will they put in transaction A and refund back a huge amount of unused gas?
  • Or will they put transactions B and C and refund little to nothing back?

The second point makes more sense to them economically right?

This is precisely why having a bloated gas limit is not a sensible way to go. It is more reasonable to set a gas limit which is just a little higher than the required amount of gas for your transaction.

The following is the average gas limit chart.

What is Ethereum Gas: Step-By-Step Guide

Image Courtesy: Etherscan

High and Low Ethereum Gas vs High and Low Fee

It should be clear to you so far that gas and ether are not the same things. Gas is the amount of computational power required while ether is the currency used to pay for that gas.

Now with the knowledge of everything we have obtained so far, let’s go through certain gas and fees scenarios.

If an operation has LOW gas, then the miners won’t even pick it up because it doesn’t have enough gas to finish computation.

If an operation has LOW fees, then it might have just enough gas to cover it but still, the miners won’t be chomping at the bits to pick it up because an operation with low fees isn’t economically appealing for them.

If an operation has HIGH gas, then it means that the operation is bloated with a high gas limit and hence the miners will not pick it up.

If an operation has HIGH fees, then the miners know that they will make a lot of money from it and will be picking it up instantly.

The currently recommended gas prices for different types of transaction speeds, according to ethgasstation are:

What is Ethereum Gas: Step-By-Step Guide

What Happens in Ethereum Gas Refund Scenarios?

In solidity, there are two commands which ensure that you get some gas refund back.

  • SUICIDE: This basically kills the smart contract. Doing so will get you back 24000 gas.
  • SSTORE: Storage deletion, which gets you back 15,000.

So, if your contract is using up 14,000 gas and deletes a storage then you should get back (15000-14000) 1000 gas refunded to you right?

It isn’t that simple.

If that was the case, then miners will lose all incentive. After all, the miners shouldn’t pay you to do your computations right?

To avoid scenarios like these, a condition was put in.

The refund that has been accumulated cannot exceed half the gas used up during computation.

Let’s take an example to clear this up.

…Suppose we have a smart contract which uses up 14,000 gas.

The gas limit that we have set up is 20,000 gas.

The smart contract also includes an SSTORAGE command.

So, how much gas will the contract creator get back post computation?

Firstly, they will get back (20,000-14,000) = 6,000 units of unused gas.

Now, the SSTORAGE command has also been used, so theoretically they should get back 15,000 gas as well.

However, the amount of gas that has been used in the contract is 14,000 and since 15,000 > 14,000/2, the REFUND generated will be 14,000/2= 7000.

So the total gas that the creator is getting back in the end is 6000+7000 = 13,000.

Let’s take another example.

Suppose this time the contract uses up 70,000 gas and it includes a SUICIDE function.

A SUICIDE function should give you 24,000 gas back which is < 70,000/2.

In this situation, the gas refund will be 24,000 + unused gas.

Criticism of Ethereum Gas. Is it Justified?

Even though the gas system has gotten praise for presenting a smoothly running mechanism which incentivizes the miners pretty positively, it has come under criticism lately for being a tad too expensive for developers and smart contract creators.

Regarding this, Danny Ryan did some interesting studies in his Hackernoon article.

Consider the following scenario:

What is Ethereum Gas: Step-By-Step Guide

When two numbers are added a million times in Ethereum it costs ~$26.55 in fees.

Danny Ryan compared that to a standard AWS system. He said that he can add two numbers a million times using python in 0.04 seconds, which going by the $0.0059 hourly Amazon EC2 rate costs $0.000000066.

This means that computation in Ethereum is 400 million times more expensive!

Based on his studies, this is the conclusion he made:

“To be fair, adding two numbers together 1 million times is a bit contrived. A well written contract would likely move such computational complexity off-chain and deal more with updating state in the contract. Storing vast amounts of data to the blockchain is also not an ordinary task. Depending on the task, a user would likely store a cryptographic reference (a hash) of the data on-chain and keep the rest of the data off-chain.

That said, we as developers need to be aware of these costs, and design dApps accordingly. We need to find the balance between on-chain and off-chain complexity, while still leveraging the decentralized capabilities of the blockchain.”

Increasing Ethereum Gas Prices Affecting Innovation

The problem with Ethereum’s high gas prices is that it makes it impossible for a developer to microtransaction payments to their projects. Lately, it has increased significantly due to network congestion from DeFi and the increasing transaction fees.

As you may be aware, DeFi (decentralized finance) apps are going through a boom period right now. Everyone wants to have a slice of the yield farming pie. As of writing, the amount of value locked up in DeFi is around $11 billion with UniSwap, Maker, WBTC being the most popular apps.

From a developer POV, the beauty of DeFi lies in its composability. One can easily incorporate different DeFi features and create a whole new app. However, with the skyrocketing gas fees, it’s becoming harder for the developers to incorporate an internal economic system that enables micropayments.

By Ameer Rosic

Details about Celo (CGLD)

Celo is a payments platform attempting to make crypto payments as easy as possible to support communities around the world who are still left without critical financial services.

Key Takeaways

  • Celo is a blockchain project focusing on improving the lives of communities around the world via swift and easy payments infrastructure.
  • The PoS network offers multiple tiers for participants: An application that doubles as a light client, full nodes, and validators.
  • The system offers a stablecoin called Celo Dollars and a governance token called Celo Gold.
  • Mainnet launch is slated for next Monday.

As Celo concludes its latest $10 million token sale, many may still be wondering what the payments platform is all about. In the following guide, Crypto Briefing will dig into the technology, the native cryptocurrencies, and the project’s broader mission.

What Is Celo?

Celo is a blockchain project focused on making crypto payments as easy as possible. Instead of having to manage complex crypto addresses, users can send cryptocurrencies using mobile phone numbers. 

Sending the platform’s stablecoin, Celo Dollars, is even possible for users who do not have the Celo app. Users can send value via WhatsApp too. To access this value, however, recipients would eventually need to download the application. 

When a user opens a Celo account, they link their telephone numbers to a specific address. A cryptographic hash of the phone number is then stored on the blockchain. To get a better understanding of how to open a Celo account, Crypto Briefing experimented with Celo’s Alfajores Testnet

How Celo Turns Phone Numbers into Blockchain Addresses
Source: Celo

The process is straightforward. 

Once users connect their mobile number with the app, the app sends an invite code via SMS which users must input to synchronize their number. After that, the app sends three SMS messages to verify the synchronization. 

According to a company blog post, users can connect multiple phone numbers to the same Celo address. 

There is also a small fee to verify the phone number. From there, the testnet gives users a small amount of Celo Dollars with which to experiment. There is a related faucet that developers and early adopters can use to replenish their Celo accounts. These are all testnet tokens and hold no real value.

There will be more discussion on the purpose of Celo Dollars and Celo Gold further along in this article. 

The simplicity of the app has led Polychain Capital CEO to describe the project as “the WhatsApp for money.”

Along with Polychain, Celo has attracted an army of notable investors to the project. Coinbase Ventures, Andreessen Horowitz’s a16z, 9YardCapital, and several well-known angel investors have contributed over $36.5 million in support. 

Adding the token offering, Celo’s coffers now hold roughly $46.5 million. Co-founder of Celo, Rene Reinsberg, told Crypto Briefing that the proceeds from the latest raise “will be used to fund ongoing development work and for community grants supporting  the ecosystem.”

The team behind the project comes from an impressive tech and finance background.

There are three co-founders, Sep Kamvar, Rene Reinsberg, and Marek Olszewski. Kamvar is the inventor of a digital reputation system called EigenTrust. Reinsberg and Olszewski sold their machine learning startup to GoDaddy. 

Other members come from other notable internet companies. 

How Does Celo Work?

On the technical side, Celo is built using the Go implementation of Ethereum and leverages a Proof-of-Stake (PoS) consensus algorithm. There are validators and nodes which help verify transactions and secure the network. 

But insofar as Celo is focused on a mobile-first user base, operating hefty and expensive validators is problematic. Once Ethereum finally transitions to a PoS network, the financial barrier of operating an Ethereum node would be 32 ether, or ~$6,344 at time of press. 

Readers should also refer to AlgorandTezos, and Cosmos for examples of successful PoS networks currently operating in the wild. 

It currently costs users more than $20,000 in equipment, $2,100 in fees per month, and a stake of 10,000 ATOM (~$25,000) tokens to run a competitive Cosmos validator. According to Reinsberg, the price is less to operate a Celo validator: 

“Each validator requires 10,000 cGLD locked up, and validator groups require 10,000 cGLD per validator affiliated with it. So, if someone wants to run 1 validator in their own validator group, they will need 20,000 locked cGLD (10k for the group, and 10k for the validator). Interestingly, this amount aligns with the average amount purchased per person in the auction, $19,646.37.” 

Though this may be prohibitive to some, Celo is looking to include as many users as possible through a multi-tiered system of light clients, validators, and nodes. 

Celo's Muli-Tiered Network
Source: Celo

The Celo mobile application doubles as a light client. Each time a user makes a payment using the application, the light client selects the cheapest, highest latency full-node in the area to confirm its transactions. 

As with any blockchain-based network there are fees for transacting. In the Celo scheme, the fees are included in the transactions sent to full nodes. Each full node can choose their lowest minimum fee to process the transaction.

The more full nodes that exist, the more efficient a network will operate. And once users recognize that they can earn money for running a full node, they too will be incentivized to launch a full node. 

There are no fees or costs for joining the network at this tier; simply run a node on a computer and begin earning. 

The third tier, validators, must be much more robust than the full node group. This is because the number of validators is limited and also because validators wield much more power in the network. This level of the network is responsible for protocol changes, providing security audits, as well as supplying hardware and software to keep the network running.

They are compensated for these contributions, much in the same way Tezos and Cosmos validators are. Like these two networks, Celo validators also hold governance properties to help steer the direction of the protocol. 

Validators that fail to operate in the best interests of the network are penalized.

What Are the Celo Assets?

Celo offers users two native crypto assets, Celo Dollars (cUSD) and Celo Gold (cGLD). 

Celo Dollars help facilitate the stable transfer of digital value between users. It is an ERC-20 stablecoin backed by reserves and pegged to the price of the U.S. dollar. 

The team has said that they will expand this offering to cover other fiat currencies. 

Unlike Celo Dollars, there is a fixed supply of Celo Gold. It is in this fixed cryptocurrency that Celo is able to manage price stability as well as much of its governance operations. Users can create cUSD by sending $1 worth of cGLD to the Celo Foundation reserve. They can also destroy cUSD by converting it back into cGLD. 

A portion of this fixed supply will be sold upon the network’s launch with the rest being created throughout the network’s life. 

Users holding cGLD can join the network as a validator or validator group, as well as propose and vote on protocol changes. They must first send some cGLD to a smart contract where the funds are locked in. The events that users can participate in are not mutually exclusive either. 

One can vote on a protocol change as well as select a validator using the same locked cGLD. For a deeper dive into the details of the governance structure, readers are invited to explore Celo’s documentation on the subject.

Users who frequently vote and are active throughout the governance process, are eligible for various rewards. The ultimate goal behind the network’s design is to entice as much participation as possible regardless of technical knowledge and financial standing. 

This in part due to the project’s grander mission. 

What Is the Alliance for Prosperity?

There are clear reasons that Celo wants to be one of the first mobile-friendly, highly-secured blockchain networks. 

They are focused on improving financial inclusion in parts of the world that have been traditionally neglected. It is for this reason that the mobile application plays such a critical role in this network. 

For the uninitiated, it is well known that many of the poorest regions in the world have turned to mobile phones to “leapfrog” technologically. 

Although they may have never experienced fixed-lines, for instance, cellphones are found throughout. Not just that, but the amount of value now being passed using mobile devices is growing every year. 

A report from the Global System for Mobile Communications (GSMA) indicates that “in 2018, $136 billion (the total value of cash-in transactions) were digitized by mobile money agents globally.” 

The number of mobile money agents even exceeds that of commercial banking infrastructure. 

Mobile Payments and Celo
Source: GSMA

To continue building on this mission, the Celo Foundation has created a so-called “Alliance for Prosperity.” This group of projects, investment funds, and service providers are all committed to improving the financial conditions where it is needed most. 

This could be in the way of payments, but also includes a number of other use cases that Celo has defined as follows: Accept, Acquire, Build, Earn, Educate, Give, Grow, Lend, Preserve, Send, Save, and Secure.

UABA has joined the @CeloOrg Alliance for Prosperity and will contribute to the Celo Ecosystem through education, community management and ecosystem support of the Celo platform.
pic.twitter.com/P9AZ1xpmR2

— United Africa Blockchain Association (@UABA_Africa) May 7, 2020

This Alliance has grown leaps and bounds since its formation and has even attracted a similar audience as that of Facebook’s Libra project. It is for this reason that there have been so many comparisons drawn between the two ventures. 

The Giving Block, a member of the Alliance and a project that helps nonprofits accept crypto donations, is exemplary of the Celo mission.

Alex Wilson, a co-founder, told Crypto Briefing:

“Celo is the first major blockchain project to put social impact at its core which makes it a great fit for us. We’re excited to help bring prosperity to all.”

Companies within the Alliance will also be able to collaborate with one another. uTrust, a crypto company helping to onboard businesses to the world of digital assets, is hoping to do exactly this.

CEO Sanja Kon, said:

“With our Payment platform and B2B solutions, we are ready to help people worldwide to open their business to millions of new users worldwide. Anyone in Africa or Latin America, can open their online business and start accepting digital currencies as a means of payment for their goods and services from anyone in the world, with truly borderless payments with low fees and no chargebacks. The fact that this is an Alliance with other amazing companies will enable synergies between Alliance members for innovative solutions worldwide.”

Concluding, Celo is one of the more ambitious projects in the cryptocurrency space. It is tackling a major social issue by delivering new technology at scale. The design is built from the bottom up for ease-of-use and ease-of-access. 

Interested parties need only download the app. If the network gains traction, there will be further incentive to participate at the full node tier or even the validator tier. With any blockchain-based network, overcoming this critical adoption chasm is the ultimate challenge. 

The mainnet launch is slated for launch on May 18, with users voting to unfreeze cGLD for Monday, according to Reinsberg.

By Liam Kelly

以太坊与开放金融

人类是基于集体想象的共同体,人类之所以能够合作,是建立在叙事和讲故事的基础之上。这个观点来自尤瓦尔·赫拉利的著名畅销书《人类简史》:

 “任何大规模人类合作的根基,都在于某种只存在于集体想象中的虚构故事,只要改变所讲的故事,就能改变人类合作的方式。” 

加密世界也是如此,每一个区块链项目的目标和生态系统都是根据特定叙事往前发展的。举个栗子,比特币从“点对点的电子现金系统”开始,经历7次叙事变迁转向了“价值存储,数字黄金”的集体想象。加密笔记之前的文章《比特币的本质是什么?比特币思维的七次变迁》已经对此有过介绍。

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今天我们聊一聊以太坊。以太坊的叙事最初从“ 世界计算机 ”开始,然后转向“ 建造永动的、不可阻挡的应用程序”。现在我们看到在以太坊周围形成了一种新叙事,社群参与者称之为“ 开放金融”或者“去中心化金融”。

这个概念来自我们从加密社区中流行的对话和叙述中获取的灵感。“开放金融”到底是什么呢?包含哪些部分?对于创业者有什么机会?

开放金融目前主要集中在建立开源、去中心化的金融基础设施方面。我们将目前致力于构建新金融生态系统的项目进行了分类整理,绘制出一幅未来版图,希望能够对你有所助益。

开放金融支持者认为,我们可以重塑当前的金融生态系统并“去中心化”他们提供的所有服务。根据梳理,该领域目前包含10个金融子行业和服务,这些将成为建立以太坊开放式金融项目的主战场:

1、衍生品

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去中心化的数字资产衍生品协议/平台,使交易员和投资者能够创建基于以太坊的加密货币衍生品智能合约。明星项目如dYdX协议,是基于以太坊的衍生品交易平台,提供可以用于做空以太坊代币 ETH 和其他 ERC20 标准代币的协议,从而让投资者可以利用协议对 ERC20 代币进行杠杆投资。

中心化替代方案:BitMEX,OkCoin和Cboe

2、支付

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分布式支付平台使用户和商家能够直接点对点进行商品和服务支付,而无需中心化的中介机构。这些平台为用户提供抗审查的、匿名的和免费的付款方式。

中心化替代方案:PayPal,支付宝,Venmo,Square

3、信用贷和借贷

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分布式的信贷和贷款平台实现了真正意义上的P2P——点对点借贷。这些项目让用户可以建立信任的同时,无需像中心化机构一样搜集个人数据,没有各种借贷的身份证,运营商认证,信用卡数据等。 代表性项目SALT(Saltlending)成立于2017年。作为一个智能撮合、自动化实现的数字资产抵押贷款平台,SALT主要从三个方面解决用户需求。其一是方便、快捷、低息的法币贷款;其二是用于抵押的数字资产不变更所有权,维持投资属性的同时增加现金流动性;最后是资产抵押并非出售,可抵消税务事件。完整的SALT贷款系统涉及借贷双方、资产保存、流动性转移、以及实现以上运行的智能合约设计与风控技术支持。

中心化替代方案:Equifax,Lending Club,SoFi

4、托管服务

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加密资产钱包是分布式的托管服务。这些产品使用户能够保护和转移基于以太坊的令牌,而无需托管银行这样的中心化机构存在。由于这些钱包不需要中介来管理它们,因此用户始终完全掌控自己的资金。

中心化替代方案:摩根大通

5、交易所和流动性

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去中心化交易所协议和流动性网络使得基于以太坊的代币的对等交易成为可能。这些平台也使得项目代币能够零门槛的利用去中心化交易所获得流动性。

中心化替代方案:纽约证券交易所,纳斯达克,港交所,外汇市场

6、稳定币

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稳定币提供法定货币的价格稳定性,同时保持加密货币的抗审查特性。

中心化替代方案:法定货币,如美元,欧元,人民币

7、KYC和身份

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去中心化的KYC(即充分了解你的客户)和身份平台使用户能够完全掌控其数据的可访问性。这些平台不需要集中注册表或身份提供商来验证个人身份。

中心化替代方案:SAS Institute,KYC Global Technologies,Clear View Systems

8、保险

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去中心化保险平台使用户无需中介即可创建和获取保险产品。这消除了传统保险公司收取的高额费用,并且提供了利基市场和创建独特保险产品的可能。比如Aigang网络的区块链协议将采用去中心化自治组织(DAO)和智能合约的物联网(IoT)设备提供新一代数字保险,该协议将被广泛应用于移动电池、无人机和无人驾驶汽车中。

中心化替代方案:传统保险公司如State Farm(美国最大的互助保险公司,首家引入UBI车险模式)

9、投资

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将资产和证券代币化使投资者能够随时进出那些非流动性投资市场。证券代币可以在市场上随时交易,这样可以更好地发现价格并增加投资流动性。比如你想投资房地产项目,一是有资金门槛,二是当你要卖房子的时候可能流动性不足哦,有价无市。如果将房子收益权代币化,很少的钱也可以参与到房地产投资,同时具备极大的流动性,随时可以在交易所变现掉。

中心化替代方案:创业公司股权,房地产和债务

10、预测市场

去中心化的预测市场平台通过提供抗审查的投注市场来提高传统预测市场的准确性。由于任何接入互联网的人都可以访问这些市场,因此极大地增加了参与者的数量,从而提高了准确性。 最具代表性项目去中心化的预测市场是Augur,基于以太坊区块链技术。用户可以用数字货币进行预测和下注,依靠群众的智慧来预判事件的发展结果,可以有效地消除对手方风险和服务器的中心化风险,同时采用加密货币(如比特币)创建出一个全球性的市场。

暗网的发展与进化

互联网上充斥着各式各样的商业活动,非法的商业活动也同样活跃。今天我们来聊聊非法网络商业活动的中流砥柱:暗网市场。

实际上,“暗网”一般指的是匿名网络上的匿名网站。原本是个中性词,因为大量黑市交易和非法活动通过暗网进行,所以很多人谈暗网色变,于是暗网被有意无意跟网络黑市等同起来了。而稍微了解点比特币历史的朋友可能知道,比特币的最早用例,则是暗网支付。

第一个使用比特币支付的暗网市场,也是最为大家熟知的叫做丝绸之路。嗯,当然不是唐僧哥哥西天取经走的那个丝绸之路。是下图这货:

丝绸之路是暗网中最具“品牌价值”的电商,堪称暗黑版淘宝。你能想到的东西都有可能在里面找到。毒品、性奴、儿童色情、军火,下限是什么?不知道。

其实这个网站的起源,颇有点理想主义色彩,一个信仰自由经济理论的年轻人准备干一番大事业:

我要创建一个经济仿真体,让人们体验:生活在一个没有系统化权力使用的世界里是什么样子。

只是后来,剧情有点魔幻,天使“走火入魔”,自由成了无底线。丝绸之路的来龙去脉不是本文的重点,感兴趣的朋友可以阅读这篇文章。我们还是回到暗网市场跟加密货币以及去中心化实践的叙事上来,因为加密货币和区块链技术的兴起,让在线黑市参与者看到了重新发明轮子的机遇,以逃避全球执法机构的打击。

本文主要八一下暗网市场的发展历程——包括起源、现状以及未来发展趋势。内容有点长,但是值得一看。

我们将不对暗网市场做出任何法律或道德判断,而是从技术和运营安全的角度入手。一件事是否合乎法律或者道德,要考虑当时、当地和观者立场。请读者自行判断。

第一阶段:明网黑市,2011 年以前

随着互联网的兴起,黑市卖家很早就利用网络来与买家沟通、做广告和收款。我有时候忍不住感叹,最早利用新科技做生意的,往往都是这一群人。比如微信、陌陌刚出来,我们还不知道怎么在上面赚钱的时候,皮肉生意已经如火如荼在上面交易。所以,互联网的早期一样,早期的黑市产品主要围绕色情服务、盗窃数据和知识产权犯罪。因此,黑市卖家主要关注的是如何交付虚拟的货物或服务,以及协助某些“个人”服务。

利用互联网来营销和买卖实体商品,如毒品,武器和伪造证件,则是从1990年代末开始的,但通常发生在少数大城市的特定社区内,原因是付款和货物交付都需要买卖双方见面。在那个年代,网络支付方式不通畅,而且对黑市卖家来说风险大,现金支付仍是主流。

2003 至 2007 年间,情况发生了根本性的改变:黑市卖家开始注意到了中心化的匿名数字货币。基于邮购的非法实物交易开始出现。这些卖家一般不会公开打广告,营销一般靠口耳相传,局限在组织严密的团体内。

后来出现了比特币,作为第一个去中心化的加密货币,它推动了黑市支付的范式转换。2011年1月诞生的暗网市场”丝绸之路” 可能是第一个融合了这种新型在线支付系统的匿名交易网络。

第二阶段:暗网黑市,2011年-2017年

“丝绸之路” 也是第一个进入大众眼帘的暗网市场。

暗网市场的浅层描述是一个托管在Tor洋葱路由等匿名覆盖网络上的网站(通过使用“洋葱路由”技术, 像剥洋葱一样,一层又一层代理连接,追查起来非常困难),商家列出商品,买家浏览和挑选商品,两者之间的支付是通过加密货币进行的。暗网还会提供额外的功能,例如买卖双方间的加密通信、声誉管理、支付托管,以及买卖双方可自由发布信息的论坛。

暗网商品一般通过邮政或是第三方物流送货。

暗网市场本身是中心化的平台,一站式地提供营销、客服、流程、声誉和支付托管等功能。这种平台对小商家非常有吸引力,他们往往没有组织层级,或者层级扁平化。用户和黑市份额都绑定在特定平台,不会具体到某个卖家。

暗网市场的一个限制因素是客户必须使用Tor或I2P等匿名访问软件才能访问这些平台。技术门槛是大部分潜在消费者进入暗网的障碍,并且要达到访问的安全性,用户只能用非移动设备如台式机或笔记本。显然不符合大多数现代消费者所需求的便利性。

暗网市场的中心化、客户与市场的约束、物流服务的使用、商家的扁平化组织层级,这些因素对暗网的安全性有许多负面影响。

虽然商家的欺诈行为被每个市场的中央声誉系统有效地制服,但买家作弊的情况却很常见。为应对这种情况,暗网市场开始提供支付托管服务。这是通过引入多方交易验证来实现的,这种交易要求买家、卖家和市场运营者中至少两方授权的情况下,款项才会移动。

执法部门对暗网市场的渗透和破坏则是更大的危害。由于大多数商品信息和卖家声誉数据都是公开发布的,暗网经常受得攻击,这些攻击使用的工具和方法往往是开源的,例如爬虫和数据分析,恶意盗取用户账户等。警方曾渗透过若干暗网调解员和管理员,甚至是卖家的账户,这些事件降低了暗网的公信力。另外,警方还直接取缔了几个暗网黑市,冻结了所有资金,扰乱了整个暗网的经济。

29岁两年狂赚77亿,35岁被判终身监禁,暗网“丝绸之路”缔造者的末路

▲丝绸之路创始人乌布利希

警方通过卧底、货运追踪和加密货币交易跟踪等方式,对黑市卖家进行追查。成功破获了一个黑市卖家以后,往往从他们的账本里拿到交易历史明细、买家发货地址等数据,这进一步损害了暗网的公信力。黑市卖家的扁平化组织,也使警方的深入渗透和对罪犯的身份识别变得容易。

最后,暗网市场往往会因为身份数据和声誉数据的丢失,之前所有的工作都泡汤,这些都会导致该网站暂时性或永久性的关闭。

新阶段,从2017/2018年开始

上述问题促进了暗网的发展。

为了防止客户被平台绑定和不受平台关闭的影响,卖家慢慢离开中心化暗网平台,开始用新的技术去搭建自己的交易系统。

卖家现在不再使用暗网上的网站,而是在主流移动即时通讯软件(如Telegram)上运营仅限邀请的群,类似国内常用的邀请制Q群、微信群。这让卖家可以更自主的管理自己的客户,不用担心平台被查封的影响。为了进一步稳定买卖双方的联系,卖家会为熟客指定联系人,为他们开单独的群,让跟踪和取缔变得更困难。公共群往往由聊天机器人来运营,能够自动回复买家咨询、下单,甚至支持全程自动化、无须人工参与的购物体验。

移动即时通讯工具的使用,让买家通过智能手机即可联系卖家,是一种更好的购物体验。这也意味着大部分的通信不再经过 Tor 或 I2P 网络,而是由买方和卖方两端所用的技术来加密保护,比如会用到流行的翻墙软件VPN。

另外一个改变是卖家不用邮政或者物流系统来送货,而是用一种秘密藏货点的方式(跟以前谍报人员传递秘密情报类似)。发货的商品被隐藏在公共场合,例如公园,买家下了单后会收到货物的具体位置,然后亲自去取货。这意味着发货和下单的分离,卖家在下订单之前就把货物藏好。买家也不用等待发货,与传统快递方式相比,大大减少了等待时间——收货往往以小时来计算。更妙的是,这种方式使买家不必再透露个人数据给卖家,因此卖家不用为如何存储隐私数据而烦恼。数据存得越少,风险越小。

使用秘密藏货的方式让卖家避开了传统快递易被追踪的风险,卖家不必再亲自去发货点,而是将整个公共场所变成藏货备选地。

加密货币仍然是主流支付方式,由于买卖之间不再有平台作为媒介,同时卖方已对买方进行过审核,双方之间不再使用支付托管。

买家和卖家的营销和审核发生在暗网的论坛和私人聊天室里,这种活动不会涉及具体交易内容。在这种虚拟场所里,买卖双方会讨论交易的流程、方法和价格。通过分享各自的经历,市场逐渐形成一套最佳实践。虽然目前还在早期阶段,这些讨论会慢慢变成一种信用记录。

除了让交易变得更安全和快捷以外,这些趋势也引起了卖家的组织结构变化:相比于从前常见的扁平化结构,如今的黑市卖家重新采用了树状组织结构,分为采购层、销售层和送货层。在每个层次下的员工不会知道高层员工的身份,也不会跟他们有任何接触。所有的通信都是数字化的 —— 通过 IM 消息和加密货币,货物只通过转移 “藏货” 地点的方式来移动。也就是金流、物流、信息流模型完全重塑,风险隔离。

采购层负责货物的采购,以及运到指定区域,然后销售人员会支付给采购层一定数量的加密货币。这样的交接过程,把采购和销售两个层级的风险分离开。

销售层负责把货物分成更小的单位,然后把藏货地点告诉送货层。送货层会把货物分成更小的销售单位,然后运到新的藏货地点,然后新地点告诉给销售层,由销售层与买家沟通。

为了防止送货人员私吞货物,销售层会做随机测试:他们会让送货人员去不同的藏货地点取货,在验证货物以后,又会指定他们运到另一处位置。通常每件货物上会有一张纸,上面会有独一无二的密文,销售层会用它来验证货物的真假。每个送货人员会以加密货币的形式,向销售层交一笔押金,如果货物验证没有通过,部分押金会被没收。目前为止,我们还没看到这种组织使用暴力去维护秩序的案例。

这种在组织内部使用移动即时通讯、加密货币和藏货的方式,让组织内部的风险完全隔离开来,处于下层的人员对于上层一无所知。即使送货人员运货时被抓获,警方也无迹可循,因为无法区分他们到底是组织人员还是普通顾客。这种组织结构能够抵抗渗透、取缔和人员被捕,具有内在的恢复能力。

另外,当销售人员提货时,他们会用一些高级技术来避开采购层的监视,这使警方很难从上而下去摸清整个组织结构。

当这种组织的成员落网了,他们一般不掌握成员身份、藏货地点和交易时间等关键信息,因为成员间的通信没有必要涉及到这些内容。

经过这些演化,结果是一个高度去中心化、细分化和恢复力强的暗网黑市运作方法,达到了收集信息少,送货快,人员间风险隔离,以及多条独立销售渠道的效果。

暗网市场的未来发展

该领域的未来发展可能会更关注客户的便利性。为了实现更好的用户体验,更多科技会被整合进暗网市场的新交易流程。比如信息服务会集成买卖双方的匿名通信、一体化的支付系统、藏货地点自动定位等功能。声誉系统会是下一个被集成的功能。

上述的信息服务具有双重用途,所有卖家,不论非法的与合法的,都会使用这些服务,慢慢集成自动回复、聊天机器人和点对点支付技术。即时通讯巨头比如微信、Telegram,甚至是 Facebook 已经涉足这个领域。

随机技术的发展,黑市的存在和需求将会更加普及。我们周围的城区将会看到各种黑市商品,可被匿名地、安全地购买。由于所需的技术不高,越来越多的人会靠黑市送货为生,勤奋的参与者会获得一笔持续稳定的收入。青少年将为黑市送货,而不是送报纸。

这种趋势会促进技术的发展,会使黑市买卖变得更方便与安全。这种送货方式会变得更普及,更多货物种类会用这种方法发送,合法的和非法的货物间界限会变得模糊。更多新服务和技术会打法律擦边球,例如支持点对点加密货币支付的锁箱。

目光再放远一点,将来整个城区会布满一次性的藏货地点,由人工或者无人机来送货,价格低廉的无人机已可在市面上买到,只缺一个研发送货技术的玩家。买卖双方都会使用无人机,通过手机就可以租到,一台无人机把货送到双方约好的一处屋顶,再由另一台无人机取货。经过了多次结点交换以后,跟踪货物变得极其困难,这个方法其实是借鉴了现有的匿名化数字通信技术。

未来可能会出现越来越多支持长距离、高载货量的无人机,价格适中,采购流程会变得更加高效和安全。

技术的发展有可能会导致对轻量级无人送货的管制放松。黑市将近在咫尺。

再开一下脑洞,结合了5G 移动网络、匿名通讯、聊天机器人、匿名加密货币、端对端加密、GPS、廉价电子设备、3D打印技术和廉价无人机的未来——短距离多轨飞行器和长距离飞机,支持基于图像识别的定位导航,还有更多的代码。

把这么多种新技术结合在一起,还有没有其他可能性呢?

By 何宇清

Chainalysis如何追踪暗网交易

美国正处于严重的阿片类流行病(opioid epidemic)痛苦之中,自2007年以来,因为过量服用而导致死亡的人数每年都在增加——事实上,这场危机的罪魁祸首就是芬太尼,因为作为一种合成阿片类药物,其功效竟然比吗啡都高出100倍。

芬太尼经销商获得了巨额利润,但与此同时,他们也开始逐渐转向暗网,并利用加密货币来销售这种新型毒品

现在,诸如Chainalysis之类的工具可以追踪相关加密货币交易来帮助执法机构调查芬太尼贩运

本文将会分析臭名昭著的芬太尼交易商ETIKING如何使用加密货币从事非法交易,该公司此前一直活跃于暗网上,直到去年才被绳之于法。在这篇文章里,你会看到执法部门如何使用Chainalysis工具将ETIKING持有的比特币地址转换为有形线索,并构建极具说服力的案例。

利润超过毒品的芬太尼

当我们提到流行的阿片类药物时,我们大多数人最先想到的就是海洛因这些街头毒品、或是奥西康等处方药。但数据表明,这些并不是全部——因为自1997年以来,过量用药致人死亡最多的其实是非法合成阿片类药物,而其中最令人不寒而栗的就是芬太尼。

由于极强的效力和危险性,只需2毫克芬太尼就能致人死亡,但恰恰是因为这种极强的效力,也吸引了大量犯罪分子铤而走险。许多毒品交易商(大多来自于非美国本土)可以很容易生产芬太尼,然后将其走私到美国,再以极高的价格出售。

更重要的是,因为芬太尼只需一点点剂量就能供很多人使用,因此交易商只需要很少就能获得高价。根据Chainalysis估计,毒品交易商前期只需要投入1000美元左右成本就能制造出价值高达780万美元的芬太尼毒品,而在同等前期成本下,海洛因只能产生大约4000美元的价值。所以对于那些不法分子来说,如此高的经济诱因让他们忽略了药物本身极高的危险性。

暗网上有许多使用加密货币的芬太尼经销商,比如Nightmare Market和Empire Market,虽然有些交易平台考虑到芬太尼极度危险的药性而选择了禁止交易,但不少卖家依然会使用一些化名来称呼芬太尼,还有些人会把芬太尼添加到各种不同的假冒药品之中继续交易,这些行为更加剧了终端用户出现用药过量的风险。

另一方面,在暗网上使用加密货币交易,对买卖双方来说都增加了一层匿名性。但是,加密货币交易依然会在区块链上留下永久记录,这也为执法机构提供了调查非法交易的机会。

借助Chainalysis,分析师可以追踪区块链中的资金、查询与加密货币交易有关的数据、并且将这些交易关联到现实世界中相应的实体。芬太尼交易商ETIKING此前在暗网AlphaBay上非常活跃,直到2018年被捕,本文将对ETIKING此前处理过的加密货币交易进行分析。

追踪ETIKING:Chainalysis可以揭示哪些暗网芬太尼交易信息?

2017年,一名佛罗里达州妇女死于过量服用芬太尼类的药物,而这些药物就是从暗网AlphaBay上一家名为ETIKING的供应商那里购买的。美国缉毒局(DEA)一开始并没有通过分析加密货币交易展开调查,而是通过线人提供的信息找到了ETIKING的卖家杰瑞米·阿奇(Jeremy Achey)并将其逮捕。

当得知这个消息之后,我们决定使用Chainalysis Reactor来分析ETIKING的加密货币活动,目的是为了搞清楚这款工具是否能对相似的执法机构调查有所帮助,而结果其实没有令人感到失望。

Reacotr挖掘出了大量信息,这些潜在的线索很可能会为执法人员提供帮助,让他们更快速地识别ETIKING,而第一步要做的,就是获取杰瑞米·阿奇的比特币地址。

ETIKING的客户向他支付购买芬太尼所使用的比特币地址:

16ozAi11YWScC88FL5tDiUbhCLLt1FHeSu

我们可以把上述地址输入到Chainalysis Reactor里,就可以看到与该地址关联的交易对手信息,此时我们就可以追溯这笔资金交易此前所使用过服务(比如是否在加密货币交易所上处理过交易),同时也能再向上追溯其他犯罪份子的信息。

上图展示了带有ETIKING地址的交易活动的一般细分,其中「接收曝光」(Receiving Exposure)显示资金从何处流入,而「发送曝光」(Sending Exposure)则显示了资金从何处流出。

如果我们仔细查看左侧「接收曝光」的信息,会发现不同类型的交易对手将加密货币发送给了ETIKING,杰瑞米·阿奇显然通过暗网接收了大量比特币,这与执法机构此前收集的情报相吻合。

而在右侧「发送曝光」中,我们看到杰瑞米阿奇其实将大量比特币发送到了交易所、以及其他服务(比如P2P交易所、商户服务,等等)。

据推测,这些可能是ETIKING希望将那些从暗网获得的比特币转换为法定货币所做的一系列交易。在“发送曝光或接收曝光”中,分析人员可以单击显示的任何类别,就能轻松拉出与ETIKING进行交易的服务列表。

举个例子,如果我们继续深入分析ETIKING「接收曝光」中暗网这一类别,那么会发现他们获得资金最多的两个暗网平台分别是AlphaBay和Dream Market。

接下来,我们可以在Reactor图表中添加这两个暗网平台来进行详细分析,如下所示:

另外,我们还可以详细分析ETIKING的「发送曝光」信息,结果会发现杰瑞米·阿奇把从暗网获得的比特币发送到了四个不同的交易所。

执法机构可能希望更深入地挖掘ETIKING在这些交易所里使用了哪些接收地址,关于这个问题我们会在稍后进一步探讨该使用哪些处理方法。在此,先让我们继续看看使用Reactor还可以发现哪些其他线索。

如果我们更加仔细地观察ETIKING「发送曝光」中的一笔不太寻常的交易,就会找到更多有价值的「花絮」。在2015年至2016年期间,我们看到杰瑞米·阿奇向位于西班牙巴塞罗那的药物效能测试实验室Energy Control International发送了0.71比特币。

这些交易表明ETIKING居然寻求合法的药物实验室来帮助测试药物质量,这在执法机构眼里绝对是另一个值得跟进的、极具价值的线索。

最后,通过回溯ETIKING的存款,我们可以识别出ETIKING使用的比特币地址集群,分别包括其最喜欢的三家加密货币交易所中使用的相同地址(绿色箭头)、来自相同暗网平台接收资金的地址(蓝色箭头)——这些地址集群很可能同样被ETIKING控制了。

综上所述,我们已经拥有了一副非常详尽的图表,让我们可以深入了解ETIKING的运营情况、以及其中连的概念。

那么,执法机构可以使用这些信息做些什么呢?正如我们在上文中所提到的那样,执法机构可以调查ETIKING将比特币存入到了哪些交易所——这是他们真正的「金矿」。

执法机构可以传唤这些交易所并获取更多与ETIKING相关的账户信息,然后他们就能知道ETIKING其实就是杰瑞米·阿奇并将其逮捕,并在Reactor披露的交易模式支持下开始审理案件。

区块链分析推动了毒品调查的发展

阿片类药物一直在夺去人们的生命,但暗网市场却为毒品交易者们提供了一个全新的、看似匿名的销售渠道。但是,正如ETIKING案件所揭示的那样,当执法人员拥有、并使用正确的调查工具,匿名性并不会阻碍他们调查那些使用加密货币交易的犯罪分子。

像Chainalysis这样的工具可以让执法机构深入了解非法获得,不仅仅定位比特币地址,还能监控交易、识别犯罪、并让案件更容易被陪审团理解。

By 平行区块链

暗网都用哪些币

如今,我们把比特币和互联网看做是同一个时代的产物也未尝不可。

上个世纪70年代,在互联网刚刚兴起的时间,“加密朋克”思想便开始在一些注重个人隐私的学者圈子中流行起来;80年代末,有人开始公开讨论加密技术是否应该被应用在政治社会领域,随后关于这类问题的争论演变成了一场运动,被后人称为“加密朋克”。

1993年,加利福尼亚大学伯克利分校数学家Eric Hughes教授在《加密朋克宣言》中写到:“电子信息时代,个人隐私在一个开放的社会环境中是必需品。我们不指望政府、公司或者其他什么组织来承诺我们的隐私权。但必须有人站出来做一个软件,用以保护我们的隐私安全。”

1996年,随着“加密朋克”队伍的不断发展,他们建立了一个邮件列表,通过邮件来进行交流和沟通,这份邮件列表的名单中有一个名字现在看来格外显眼——“中本聪”。当初在不少科学家和极客眼中,“中本聪”就是那个为了个人隐私安全挺身而出的人。 

诞生于“加密朋克”时期的比特币核心思想萌芽,经过多年的沉淀和探索,终于在2009年成功落地。那一年,中本聪发布了《比特币:一种点对点的电子现金系统》的论文,详细论述了比特币去中心和匿名性的特点。

但事与愿违的是,比特币没能成为个人隐私的保护伞,反而与暗网的需求不谋而合。2013年10月1日,暗网“丝绸之路”的缔造者Ulbricht被逮捕,丝绸之路通过比特币做非法交易的事实浮出水面,整个平台26000枚比特币全部被查封,Ulbricht本人被判处无期徒刑。据FBI公布的数据显示,丝绸之路从创建之初到被迫关闭,总交易额在950万枚比特币左右。这一事件,让比特币名声远扬,从此与暗网和非法交易结下不解之缘。

早在2012年就曾有数据显示,30%的比特币交易指向暗网。到了2014年,六大暗网中平均每天的比特币交易量达到65万美元,而当年BitPay平均每天的交易量才只有43.5万。暗网市场成了比特币在现实世界最大的价值来源。

而比特币在不见天日的暗网世界风光了近八年时间,却从2016年起走上了下坡路,其在暗网中的市场份额从之前的30%下降到了这两年的1%。数据显示,靠暗网发家的比特币正在被暗网所抛弃。

1. 悄悄“崛起”的莱特币

今年二月,加密货币市场调查公司Recorded Future通过对150个暗网市场及地下交易网络留言板的调查发现,比特币的好评率大幅下降。

从2016年起,网络犯罪分子的地下组织中,关于加密货币的功能、安全性以及可用性的讨论频率开始增加。大部分人都在吐槽比特币作为一种支付方式的手续费高昂以及转账龟速;与此同时,莱特币的使用率逐渐上升,成为了暗网中仅次于比特币的,第二大受欢迎的加密货币,其发展之势大有超过比特币的劲头。

被“抛弃”的比特币与前赴后继的暗网新宠

(图片来源:Recorded Future)

用今天的话来说,莱特币实际上就是比特币的一种分叉币,和比特币使用了相同的代码框架,除了挖矿算法不同之外,其他的功能和特性几乎一模一样。

自2017年年中以来,随着价格的大涨,比特币在全球用户、投机者以及机构投资者中的受欢迎的程度急剧增加,这给其网络带来了巨大的负荷,从而导致支付手续费暴增,链上交易拥堵不堪。在暗网,大部分交易都是通过线上进行的,你不知道在电脑的另一端坐着的是道貌岸然的伪君子、十恶不赦的无赖还是手艺精湛的黑客,所以时间就是金钱,每一秒钟的拖延都意味着资产被盗的风险。

况且,组织庞大的暗网系统实际上是由日常性的小额支付支撑起来的。因此,当比特币的交易手续费动不动就超过成交额30%的时候,与比特币功能相似,但交易速度和手续费价格俱佳的莱特币,就成为了暗网商家们青睐的对象。

被“抛弃”的比特币与前赴后继的暗网新宠

(图片来源:Recorded Future)

从Recorded Future的调查结果可以发现,方便快捷的莱特币正在欧洲市场迅速虏获人心;但在英文市场,人们似乎更加关注交易的安全性和匿名性。

加密货币分析公司Chainalysis日前曾发出声明表示,他们可以追踪与犯罪活动相关的加密货币钱包;Chainalysis 首席执行官 Michael Gronager 认为,是由于目前使用加密货币进行违法活动的人数还不是很多,因此追踪犯罪行为相对容易;但对于门罗币和Zcash这种以匿名性为中心的加密货币仍然是难以追踪的。

2. 门罗币的晋升之路

在各国情报机构的穷追猛打下,比特币和莱特币的匿名性几乎不堪一击。

目前,大多数的银行和加密货币交易平台都添加了直接与用户个人身份信息挂钩的KYC功能,任何通过这些银行进行的比特币与法币的兑换,都有迹可循;通过这类交易平台进行的比特币交易,其区块链上不可篡改的数据,都会成为证明资产流向的铁证。

从斯诺登泄露的政府机密文件来看,美国国家安全局(NSA)从2013年开始就一直在通过代号为“OAKSTAR”的计划追踪比特币用户的行动,目前该机构的这种监控行为似乎已经开始向明确用户身份的方向发展了;据最新的文件内容,NSA可能正在通过“OAKSTAR”的另一个子项目“MONKEYROCKET” 来进一步锁定发起比特币交易用户的真实身份。

被“抛弃”的比特币与前赴后继的暗网新宠
被“抛弃”的比特币与前赴后继的暗网新宠

(图片来源:网络)

而对暗网用户来说,一种匿名性更强,更难追踪的数字货币成为了他们更为迫切的需求。

这个时候,门罗币(Monero)就在暗网闪亮登场了。

与莱特币直接复制自比特币不同,门罗币硬分叉自2012年7月发行的“Bytecoin(字节币)”。字节币是第一个基于CryptoNote算法的隐私性加密货币;但由于在它公诸于世之前,就已经被预挖了将近82%,因此Riccardo Spagni等人在字节币的基础之上发行了门罗币,又在其中添加了环形签名和混淆地址等技术来增加匿名性,使门罗币能够达到隐藏交易金额和交易双方地址信息的目的。

美国陆军和美国国家安全局也对开发追踪门罗币用户的方案而感到头疼。

2016年8月底,当时主要的两个暗网市场OASIS和阿尔法湾宣布整合门罗币的支付功能。然而一年之后的2017年7月,最大的暗网市场阿尔法湾被查封,美国FBI对外宣称,没收了该网站价值近880万美元的加密资产,其中包括1605枚比特币、8309枚以太坊、3691枚Zcash,但唯独由论坛匿名管理员保管的门罗币,由于缺乏私钥而数量不详。今年四月,克隆阿尔法湾发展起来的替代网络Empire宣布,接受门罗币支付。

被“抛弃”的比特币与前赴后继的暗网新宠

(图片来源:bitcointalk)

至此,门罗币至少已经在暗网市场生存了三年时间。但是,只有强大的匿名性是无法完全获得暗网信赖的,今年四月为了抵抗比特大陆在算力方面的垄断,门罗币宣布将实施硬分叉修改挖矿算法,而此举险些让它失去在暗网中的地位。

通常情况下为了实现功能升级,门罗币基本上是每六个月强制硬分叉一次,然而其针对比特大陆的方案打乱了原有的分叉节奏,而这也被反映在了暗网市场当中。当时,不少用户在暗网论坛上投诉,硬分叉之后,他们从旧的钱包中提出了门罗币,但是无法通过升级之后的新钱包接受这笔资金,以至于他们根本不知道自己到底还有多少门罗币可以使用。

对此,暗网市场Dream Market 表示,暂时停止使用门罗币的支付选项;直到四月底,门罗币的硬分叉事件告一段落,功能稳定之后,他们才又重新开启了对门罗币的支持。

但一言不合就硬分叉的技术发展方式,也成了门罗币在实际支付场景中的不定时炸弹。

3. “黑暗”中的达世币

达世币DASH,原名叫做DarkCoin;光听名字就知道,它是为暗网而生的。

目前,达世币总市值排名第14位,相对币圈个个堪比“戏精”的生存模式,达世币则显得低调了许多。但这并不影响它成为暗网中位列于比特币和莱特币之后的,第三大受欢迎的加密货币。和莱特币一样,达世币也是基于比特币的代码框架开发而来的。

它在比特币的基础之上添加了双层奖励机制,即为整个区块链网络的全节点增加了补偿方案,所有全节点被称为达世币网络的主节点,每个主节点必须对网络提供服务,同时抵押代币,以利息的方式获取运行全节点所需要的资金和带宽资源。这种机制倒是和EOS的超级节点模式有些相似,但不同的是,达世币的主节点不需要通过竞选,而是自主选择是否要加入网络。

达世币的匿名性是通过混币技术所实现的。所谓混币技术,指的是将几笔交易的全部代币混在一起,然后再发往不同的收款方,这样一来每一次混币,都会使得追查到交易发起方地址的难度呈指数型增加。通常达世币会进行三轮混币,来提高其匿名性。

除此之外,达世币还可以做到防篡改的即时交易。它利用主网中随机六个主节点暂扣支付DASH的方式,先确定完成支付过程,使达世币即时到账,然后才在网络中进行交易广播,等待六次确认之后,收款方才能够继续使用刚收到的达世币。

根据Recorded Future的调查结果,截至今年二月份,达世币在暗网中的接受率已经超过20%。

被“抛弃”的比特币与前赴后继的暗网新宠

即使在市场舆论方面没有引起大风大浪的达世币,依靠其天生为暗网而生的匿名性和即时交易的特性也得以成功上位。

4. 暗网市场所使用的加密货币最终都将成为主流币?

一位加密货币论坛中的活跃者曾评论称:“通常,毒品贩子所使用的加密货币最终都将成为主流币”。

不可否认的是,暗网确实促进了加密货币市场的发展。

  • 在暗网中占据主流地位的比特币八年暴涨300万倍,而其价格的上涨吸引了众多用户和投机者参与其中,最终也成为使其被暗网抛弃的最大原因之一;
  • 达世币2017年增幅8000%,最高时其增幅是比特币的六倍;
  • 动荡的门罗币受暗网影响最为明显,2016年阿尔法湾和OASIS两大暗网宣布接受门罗币,使其价格增长50%,2018年4月,当门罗币身处硬分叉风波时,阿尔法湾的替代网络Empire添加门罗币支付选项,使其价格逆转跌势,掉头向上。
被“抛弃”的比特币与前赴后继的暗网新宠
被“抛弃”的比特币与前赴后继的暗网新宠

但实际上,与其说莱特币的便宜便捷、门罗币的匿名特性以及达世币的即时支付是暗网的需求,不如说是加密货币在现实应用场景中的实际需求仅仅于此。大多数技术都是带着美好的愿景被开发出来的,但能坚持初心的寥寥无几,聊天工具Facebook成了虚假新闻的集散地,社交平台Twitter也成了ISIS招兵买马的媒介,到了加密货币自然也不列外。

在加密朋克的理想中诞生的比特币,却在暗网巨大的匿名性需求中成长,在市场投机性的催化下壮大;以保护隐私和去中心为初衷的比特币,最终难免沦为不法者逃避罪责的工具或者投机者实现暴富的手段。

现在,从暗网发家的比特币开始向主流金融圈靠拢,而更多的加密货币步上了比特币的后尘。那些想要通过加密货币实现财富自由的投机者们,在担心自己钱袋子的同时,也该担心一下正在失去暗网“宠幸”的比特币,之后的应用场景会在何方?或者下一个被暗网抛弃的代币将会是谁。

What is Yearn Finance

Yearn Finance is a gateway for a set of Decentralized Finance solutions, powered by the Ethereum blockchain, that allows one to maximize your investments through lending aggregation, yield-generation, and insurance. The revolutionary YFI can be seen as the first step towards a secured and better investment in the DeFi. While volatility seems to be the most consistent characteristic of the overall cryptocurrency market volatility, its effect on the YFI token seems undeniably low.

The following article explores what Yearn Finance is, the basics, and how you can use it.

Tl;dr – think yield farming on autopilot.

1. What is Yearn Finance?

Essentially, Yearn Finance allows users to automatically get the highest yields on several DeFi platforms.  Like we mentioned before, Yearn Finance runs on the Ethereum blockchain and provides lending aggregation, yield generation, and insurance. Yields on Yearn Finance

Yields on Yearn Finance

It’s maintained by a series of independent developers while being governed by YFI holders. It was developed by Andre Cronje, a well-known cryptocurrency expert with extensive knowledge in mobile development and distributed systems. Prior to dedicating his time to developing Yearn Finance, Cronje was a Head of Technology for several companies where he started grasping blockchain and cryptocurrencies. After that, he dove deep into this technology and performed roles as advisor, engineer, analyst, and consultant for a series of companies such as CryptoCurve or Kosmos Kapital and projects such as FUSION foundation or Fantom Foundation.Yearn Finance comprises four core products that function together seamlessly to enable a smooth running of the protocol and enable users to gain on their investment: 

Vaults: A passive-investing tool that automatically generates yields through capital pools;

Yinsure: A KYC-less insurance policy for smart contracts;

Zap: A tool that allows you to swap in and out of certain liquidity pools;

Earn: A lending aggregator that continuously searches for the best interest rates.

2. Highs and Lows of YFI

To better understand the Yearn Finance of today, let’s take a look at its history.

Initially, Yearn.Finance was created by Cronje with the goal of allowing investors to find the best yield for their investments in a practical and automatic way. Its native token is called YFI and acts as a governance token concerning voting and decision-making on the protocol. 

YFI was listed on Coinbase Pro on the 11th of September of 2020, and four days later it was ready to be used for trading. Coinbase described Yearn.Finance as a decentralized platform with the automated functions of aggregated liquidity and marketing movement of providers’ funds between platforms like dYdX, Aave, and Compound.

The surge of YFI is one of the more unexpected coin booms in recent cryptocurrency history.

Just four days after its listing on Coinbase Pro, YFI’s price grew from $32,382 to $41,381. This burst in per-token price met with Bitcoin’s price at around $43,966.Experts concluded that the explosive burst of YFI might be related to its union of strong technical, new products, yield farming, and the growing popularity of DeFi liquidity pools. 

The DeFi and Yearn Finance communities look towards its products such as Vaults, Yinsure.Finance, and “StableCredit USD” to further push the network (and price) forward.

3. The evolution of Yearn Finance

The Yearn Finance protocol started under the name of iEarn and it was built single-handedly by Andre Cronje. The protocol suffered an attack in 2020, which led to the founder taking time off the platform following an outcry from the project’s community. 

This attack basically exploited the fact that Cronje tests his software in a “live” environment. This allowed a user to “lose” more than $400k via slippage in Curve Finance, but it also allowed his friend to step into the scene with large pockets and reverse the slippage. This then resulted in a small loss for the first user mentioned here and a small profit for a third user. Even if a lot of people were suspicious, the attack was not as damaging as it could have been.Yearn finance

Various proposals on Yearn finance

In any case, he came back to the protocol and the project was rebranded to Yearn Finance.

The rebranding also resulted in the introduction of new products on the platform such as Vaults, StableCredit, yInsure, and Earn. However, it was the introduction of the protocol’s native token YFI that projected the protocol to the spotlight

Before the token’s introduction, the available liquidity on the protocol was just $8M but this changed swiftly to more than $400M in just a week after launching the token.

Initially, only the Founder Cronje had the right to mint tokens, which has since been extended to include 9 members. These nine members are the closest there is to a board of directors. To make any changes to the protocol, at least 6 out of those 9 members need to approve through a Multi-sig wallet. Only active members of the DeFi community are included in the Multi-signature ownership and Cronje is not included as part of the signatory.Yearn finance

Various proposals on Yearn finance

The Yearn Finance community members and contributors have explored the addition of extra YFI tokens to incentivize developers.  They planned to add 6666 tokens to the existing pool of 30.000 and voted on the proposal on January 28, 2021. The vote to inflate the token supply by 22% passed with 1670 YFI voting in support of the proposal and 331 YFI voting against it.

4. How to use Yearn Finance

Now that you know what is Yearn Finance, let’s explore how people are actually using it. 

You can use Yearn Finance for trading and lending through its product known as Earn, Zap, and APY. For example, Earn allows users to earn the highest interest on lending via all lending protocols. Earn searches all these lending protocols to get the best rate for users. Users can earn these interest rates by depositing USDT, sUSD, DAI, USDC, and TUSD on the Yearn Finance protocol.

Zap enables users to make many investments in a single click. That means that you can exchange your USDC for yCRV in a single stroke rather than repeated steps across different platforms. This is time-saving and cheaper in terms of the transaction cost. If tokens like yCRV are unfamiliar to you, do not worry. They do involve a few more steps to get but once you dominate the platform, it will come naturally to you. 

Annual Percentage Yield (APY) on the other hand, analyzes the lending protocols available to Earn users then gives an estimation of the amount of interest they should expect to make annually for a specific amount of money.

You can also use Yearn Finance vaults on the protocol to gain earnings on your investment. However, it is a bit more complex than the other products we have talked about. Yearn Finance vaults utilize the protocol’s self-executing code to enable traders to track active investment strategies. There are 10 vault strategies available to users as of August 30, 2020.

However, for users to grasp how vaults work they have to be familiar with code as the strategies on it are expressed in Solidity. It sounds complicated, but actually investing in a vault isn’t as technical as it seems. The user interface on Yearn Finance does a pretty good job at simplifying the process. 

Essentially, users will see a list of vaults with historical ROIs and can deposit USDC into any given vault. Then, the profits generated are used to invest in the same asset of each vault, creating a “continuous buy-and-hold strategy”. Finally, for those that wish to withdraw their funds, they will be proportionally allocated, based on the share of contribution of each investor to the pool.

Final Thoughts: Is Yearn Finance Legit?

The astronomical rise of its token YFI put it on the radar, but Yearn Finance is more than just a rapidly growing token. Yearn Finance has cemented itself as a key player in the DeFi market due to its ability to interface with multiple pools and offer the best possible rates.

Its technical capabilities allied with a valuable token and a large and passionate community make this project one of the most exciting ones in the DeFi space. The expectation of getting new products, new Vault strategies, and new integrations cannot allow any crypto enthusiast to avoid following the Yearn Finance community.

By Alex Moskov

What is Sushiswap

SushiSwap is the newest decentralised finance (DeFi) liquidity pool platform. With SushiSwap, people can add their tokens into the liquidity pools and earn. In this article, we’ll have a look at the Sushi Swap platform and how to participate in the liquidity pool. Anyone can participate.

View Sushi Price Chart

Summary

  • SushiSwap is a platform that allows anyone to provide liquidity. In return, the person gets rewarded with token(s) and SUSHI tokens. 
  • As of September 4, 2020, there are 1 billion dollars of locked liquidity.
  • Possibility of very high APY (up to 1,000%) on some liquidity pools. You can check the current yields on SushiBoard.

Why is SushiSwap so popular?

Sushi Swap markets itself as an “improved and community-friendly” Uniswap. Unlike a traditional exchange like Binance where they employ market makers, SushiSwap is a community-oriented platform where users provide liquidity. In return, they get rewarded. Indeed, the users are the market makers.

SUSHI token

SUSHI tokens are given as rewards for liquidity mining. The token allows its holders to participate in the governance of the platform and entitles them to a portion of the fees paid to the protocol by traders. For the governance of the platform, SUSHI holders can submit a SushiSwap Improvement Proposal (SIP) which token holders can vote on with their tokens.

Of course, some people also speculate on the prices of SUSHI and the token can be traded on major exchanges such as Binance, FTX and OKEx exchanges.

Advantages of SushiSwap

There is no KYC (Know Your Customer) policy. This means anyone can trade and contribute to the liquidity pools. The platform is permissionless, meaning anyone can contribute millions of dollars without asking for permission. 

Earn tokens from Sushi Swap. SUSHI is Sushi Swap’s native token. When you contribute to the liquidity pool, you earn sushi tokens. You can exchange SUSHI for ETH. 

Sushi Swap model: 0.25% go directly to the active liquidity providers and 0.05% get converted back to SUSHI and is rewarded to sushi holders. 

Sounds interesting? Let’s visit Sushi Swap’s home page.

SushiSwap beginners guide 

When you first arrive on Sushi Swap’s home page, you’ll see this:

Sushiswap.fi homepage
Sushiswap.fi homepage

Click on “Unlock Wallet” or “See The Menu”, either way you will need to connect your ETH wallet in order to this platform. 

Sushi Swap has the option to use MetaMask, WalletConnect or many other non-custodial wallets. Pick the one of your choice.

Connect wallet
Connect wallet

Give permission for Meta Mask or Wallet Connect to connect to Sushi Swap. Once you’re connected, you’re ready to add your tokens into the liquidity pools.

Liquidity pools
Liquidity pools

You’re presented with various liquidity pools (LPs). Each liquidity pool has a different annual percentage yield (APY).

In this example, I’ll contribute to the ETH-USDT pool. I add my USDT into the liquidity pool. In return, I’ll get a percentage of USDT and SUSHI tokens. Think of Sushi Swap as a “community revenue share” model.

Contribute to liquidity pool
Contribute to liquidity pool

To contribute to the liquidity pool, click “Approve USDT-ETH UNI-V2 LP” and give your Meta Mask permission to move your tokens into the liquidity pool. 

Now what? You wait. The “SUSHI earned” box should populate with your earned SUSHI. You can withdraw your SUSHI token anytime by clicking on “Harvest”.

2020 roundup and new roadmap!

Many things have happened within the Sushiswap ecosystem in the last months: it is now time for a quick recap and to look at what the future will bring to this project!

The number of all the partnerships finalized by the protocol is countless, but one of the most important ones, if not the most important, is certainly the merger with Yearn. The news also sparked controversies: Sushiswap was still considered a sort of “copycat” of Uniswap by some, and when Andre Cronje (Yearn’s father) wrote an article on how it is difficult to build in Defi and how conversely it is easy for anyone to just copy other people’s code, this wasn’t seen as really coherent. The collaboration was born to allow the two teams to cooperate on Deriswap.

Nevertheless, Sushiswap has been evolving so much that, according to Mira Christanto (one of Messari’s data analysts) they have “put their past behind” and, not being backed by Venture Capitals, they can move faster than competitors. January has seen a real growth in Sushiswap’s TVL (now at $2.1 billion), mostly at the expense of Uniswap’s.

Among the important milestones in 2020, we find Onsen, the new Sushiswap liquidity mining incentivization program which replaces the old Menu of the week. It brings communities together into the ecosystem and allows voted tokens to become accredited and participate in the mining program. The website also has a new layout of and a lite version.

2021 Roadmap

As the new year has already begun, it is also interesting to have a look at what Sushiswap is working on for 2021. The team released a long and detailed roadmap in early January. Notable upgrades are the following:

  • Mirin will be the new upgraded version of Sushiswap’s V3 protocol. It will include many new features like franchised pools, double yield, dynamic yield rebalancing, and many more as you can read here.
  • Bentobox (which should have launched in January) was born in the team’s mind as a new Lending Platform. While they were was working on its code though, it became something more. In simple terms, it will be a single vault that holds all tokens for any protocols and future extensions. It will support several oracles and it will also benefit all the $SUSHI holders.
  • Miso (Minimal Initial Sushi Offering) will be a sort of token launchpad, designed to drive new projects’ launches on the platform. It will include crowd sale options, IDOs (Initial Dex Offering), auctions, and more. We could think of it as something similar to Binance’s launchpad.
  • As Ethereum fees are and will keep growing in the next future until ETH2 will be a reality, most platforms are studying alternative solutions for their users such as Layer 2 possibilities. Unlike Uniswap, which is working on Optimistic Rollups, Sushiswap decided to move in sync with the greater Yearn ecosystem and thus will probably offer Zk-rollups options.

Together with all these big news, Sushiswap is also planning to move to a new domain as the old one, in their view, is not enough to describe the diversity of the platform anymore. A transition to a fully decentralized governance structure is also planned by the end of 2021. Last but not least, Sushiswap has created a proposal page for people to express their ideas on what they would like to see on the platform. Everyone can be a chef is the place where you can voice your opinion if you like to suggest new ideas.

FAQs

Is it risky to provide liquidity to SushiSwap?

The pool could get hacked if the code isn’t audited. There have been cases of hackers draining funds from smart contracts. It helps if the code is audited by a reputable firm. In the case of SushiSwap, it has been given a “security review” (not an audit) by Quantstamp. 10 issues were identified but they do not appear to be fatal. Subsequently, Peckshield had completed an audit on SushiSwap. They found no critical or high severity issues relating to business logistics but 2 high severity opsec issues that need to be fixed through extra care with deployment.What is the reward model of Sushi Swap?

0.25% go directly to the active liquidity providers and 0.05% gets converted back to sushi and is distributed to active SUSHI holders.

By Michael – Boxmining