In August 2019, Coinbase announced that it was targeted by a sophisticated hacking attack attempt in mid-June. This reported attack used spear-phishing and social engineering tactics (including sending fake e-mails from compromised email accounts and created a landing page at the University of Cambridge) and two Firefox browser zero-day vulnerabilities. One of the Firefox vulnerabilities could allow an attacker to escalate privileges from JavaScript on a browser page (CVE-2019–11707) and the second one could allow the attacker to escape the browser sandbox and execute code on the host computer (CVE-2019–11708). Coinbase's security team detected and blocked the attack, the network was not compromised, and no cryptocurrency was stolen.[39][40][41] 


2) Pseudonymous: Neither transactions nor accounts are connected to real-world identities. You receive Bitcoins on so-called addresses, which are randomly seeming chains of around 30 characters. While it is usually possible to analyze the transaction flow, it is not necessarily possible to connect the real world identity of users with those addresses. 


^ Iansiti, Marco; Lakhani, Karim R. (January 2017). "The Truth About Blockchain". Harvard Business Review. Harvard University. Archived from the original on 18 January 2017. Retrieved 17 January 2017. The technology at the heart of bitcoin and other virtual currencies, blockchain is an open, distributed ledger that can record transactions between two parties efficiently and in a verifiable and permanent way.

什么是RCN Cryptocurrency

This flexibility makes Ethereum the perfect instrument for blockchain -application. But it comes at a cost. After the Hack of the DAO – an Ethereum based smart contract – the developers decided to do a hard fork without consensus, which resulted in the emerge of Ethereum Classic. Besides this, there are several clones of Ethereum, and Ethereum itself is a host of several Tokens like DigixDAO and Augur. This makes Ethereum more a family of cryptocurrencies than a single currency.


One of the most important problems that any payment network has to solve is double-spending. It is a fraudulent technique of spending the same amount twice. The traditional solution was a trusted third party - a central server - that kept records of the balances and transactions. However, this method always entailed an authority basically in control of your funds and with all your personal details on hand.
When it comes to other, less popular cryptocurrencies, the buying options aren’t as diverse. However, there are still numerous exchanges where you can acquire various crypto-coins for flat currencies or Bitcoins. Face-to-face trading is also a popular way of acquiring coins. Buying options depend on particular cryptocurrencies, their popularity as well as your location. 


Welcome to the 32nd Coin Report. In today’s report, I will be assessing the fundamental and technical strengths and weaknesses of ExchangeCoin. This will be comprised of an analysis of a number of significant metrics, an evaluation of the project’s community and development and an overview of its price-history. The report will conclude with a grading out of 10. ExchangeCoin was launched in November 2017 with an ICO that raised 650 BTC, equating to over $5,000,000 at the time. The token issued, EXCC, has a maximum supply of 32,003,133, with 4mn EXCC sold during the ICO. Further, the project also has a premine of 12.1mn EXCC, equating to 37.95% of the maximum supply (from which the 4mn was sold to the public in the token sale). The token itself operates on the Equihash algorithm, and underwent a hard fork in July 2018, after which the network migrated to a dual Proof-of-Work/Proof-of-Stake consensus mechanism, with 30% of block rewards rewarded to stakers and 70% to miners. The block reward is progressively diminishing, with the current reward at 24.5 EXCC per block, with 2.5-minute block times.


To understand the revolutionary impact of cryptocurrencies you need to consider both properties. Bitcoin as a permissionless, irreversible, and pseudonymous means of payment is an attack on the control of banks and governments over the monetary transactions of their citizens. You can‘t hinder someone to use Bitcoin, you can‘t prohibit someone to accept a payment, you can‘t undo a transaction.


On 21 November 2017, the Tether cryptocurrency announced they were hacked, losing $31 million in USDT from their primary wallet.[71] The company has 'tagged' the stolen currency, hoping to 'lock' them in the hacker's wallet (making them unspendable). Tether indicates that it is building a new core for its primary wallet in response to the attack in order to prevent the stolen coins from being used.

比特币与莱特币都采用了区块链技术,且都有51%攻击的问题。它们采用区块链技术,所有历史记录按照时间先后顺序,打包成一个个单独的区块,再把这些单独的区块链接在一起形成一个总账本 [5]  。这些区块内除了包含交易记录外,还包含新发行的莱特币和交易的手续费,这两笔钱支付给挖矿的矿工作为酬劳。无论谁挖到该区块,那么该区块内含有的新发行的莱特币和交易的手续费这两笔钱都归挖到者,以鼓励矿工积极参与结算。区块链技术容易产生51%攻击的问题:无论任何组织甚至个人,只要掌控某一种基于区块链原理的虚拟货币的全部运算能力的51%,这个人或组织就能够任意操纵该虚拟货币的所有交易。如果区块链只认运算能力最大者,谁的运算能力最大,谁就能抢到下一个区块,如果某个个人或组织掌控了全部运算能力的51%,那就意味着没人比他运算能力更强,故而他就可以随意操纵。所以,对于基于区块链原理的虚拟货币,参与挖矿的越多就越健壮,运算能力越分散就越健壮;挖坑者越少越脆弱,运算能力越集中就越脆弱,矿池越集中也就越脆弱 [1]  。
The validity of each cryptocurrency's coins is provided by a blockchain. A blockchain is a continuously growing list of records, called blocks, which are linked and secured using cryptography.[23][26] Each block typically contains a hash pointer as a link to a previous block,[26] a timestamp and transaction data.[27] By design, blockchains are inherently resistant to modification of the data. It is "an open, distributed ledger that can record transactions between two parties efficiently and in a verifiable and permanent way".[28] For use as a distributed ledger, a blockchain is typically managed by a peer-to-peer network collectively adhering to a protocol for validating new blocks. Once recorded, the data in any given block cannot be altered retroactively without the alteration of all subsequent blocks, which requires collusion of the network majority. 


“If the trend continues, the average person will not be able to afford to purchase one whole bitcoin in 2 years. As global economies inflate and markets exhibit signs of recession, the world will turn to Bitcoin as a hedge against fiat turmoil and an escape against capital controls. Bitcoin is the way out, and cryptocurrency as a whole is never going away, it’s going to grow in use and acceptance as it matures.”