Zcoin is a privacy focused cryptocurrency that was originally built on the Zerocoin protocol. However, given a number of vulnerabilities in that protocol, they recently moved to a new "Sigma" Protocol that was launched in 2019. Transactions are made private by a privacy enhancement in the protocol called "minting". Before you are able to send transactions, you have to mint new coins. Given that all coin’s transactions originate from a newly minted coin, it is hard to track the origin. Privacy on Zcoin is made possible through the use of Zero Knowledge proofs. You also have Tor integration as well as their recently released "Dandelion" protocol. This will further help to cement user privacy on the network. ZCoin uses a the Merkle Tree Proof of Work algorithm (MTP). This is a memory hard algorithm that is considered to be ASIC resistant and hence less prone to centralisation. Zcoin also has a masternode architecture with their "Znodes" (require 1,000 XZC to stake). In compensation for running this full node, the Znode will receive 30% of the newly minted Zcoins. The team behind the Zcoin protocol is quite extensive experience in blockchain engineering, software development, cryptography and many more. The developers have also been hard at work if you take a look into their GitHub repository. When it comes to markets, XZC is listed on a number of exchanges including MXC, Coinex, Binance, Huobi etc. There appears to be reasonable liquidity on these exchanges which will ease execution. However, XZC is still volatile so trade with caution. *Coin Bureau's views are not investment advice. Do Your Own Research.


In May 2018, Bitcoin Gold (and two other cryptocurrencies) were hit by a successful 51% hashing attack by an unknown actor, in which exchanges lost estimated $18m.[citation needed] In June 2018, Korean exchange Coinrail was hacked, losing US$37 million worth of altcoin. Fear surrounding the hack was blamed for a $42 billion cryptocurrency market selloff.[72] On 9 July 2018 the exchange Bancor had $23.5 million in cryptocurrency stolen.[73]


Coinbase has lost my money twice now. Once was due to an old account that, thanks to a bug in their verification process, I cannot re-authenticate. I bought 1 bitcoin back when they were only about $50 each with Coinbase. That money is gone forever now. And I acknowledge that it’s my fault that I did not set up a forwarding email with Coinbase, their support just refused to help. The second time was a month ago. I made a trade on Coinbase, and for some reason, the app glitched to think I have 5x more money than I actually… Read more »

NO WAY. How do some many people trust Coinbase with their money When their website’s software is full of faulty programs that they won’t or can’t fix. IE, I tried to add a new debit card to my account. I gave them my cards info and was told to check my account for two small charges made by coinbase and enter the amounts in a designated page. Both amounts were over $3.00, but the verification page only allowed me to submit amounts under $2.00. I was never able to add another card to my account. For me, no big deal,… Read more »


Once you bought your cryptocurrency, you need a way to store it. All major exchanges offer wallet services. But, while it might seem convenient, it’s best if you store your assets in an offline wallet on your hard drive, or even invest in a hardware wallet. This is the most secure way of storing your coins and it gives you full control over your assets.

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To realize digital cash you need a payment network with accounts, balances, and transaction. That‘s easy to understand. One major problem every payment network has to solve is to prevent the so-called double spending: to prevent that one entity spends the same amount twice. Usually, this is done by a central server who keeps record about the balances.
Coinbase has lost my money twice now. Once was due to an old account that, thanks to a bug in their verification process, I cannot re-authenticate. I bought 1 bitcoin back when they were only about $50 each with Coinbase. That money is gone forever now. And I acknowledge that it’s my fault that I did not set up a forwarding email with Coinbase, their support just refused to help. The second time was a month ago. I made a trade on Coinbase, and for some reason, the app glitched to think I have 5x more money than I actually… Read more »


The legal status of cryptocurrencies varies substantially from country to country and is still undefined or changing in many of them. While some countries have explicitly allowed their use and trade,[51] others have banned or restricted it. According to the Library of Congress, an "absolute ban" on trading or using cryptocurrencies applies in eight countries: Algeria, Bolivia, Egypt, Iraq, Morocco, Nepal, Pakistan, and the United Arab Emirates. An "implicit ban" applies in another 15 countries, which include Bahrain, Bangladesh, China, Colombia, the Dominican Republic, Indonesia, Iran, Kuwait, Lesotho, Lithuania, Macau, Oman, Qatar, Saudi Arabia and Taiwan.[52] In the United States and Canada, state and provincial securities regulators, coordinated through the North American Securities Administrators Association, are investigating "bitcoin scams" and ICOs in 40 jurisdictions.[53]


The term altcoin has various similar definitions. Stephanie Yang of The Wall Street Journal defined altcoins as "alternative digital currencies,"[20] while Paul Vigna, also of The Wall Street Journal, described altcoins as alternative versions of bitcoin.[21] Aaron Hankins of the MarketWatch refers to any cryptocurrencies other than bitcoin as altcoins.[22]

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]  。


Then, in early 2009, an anonymous programmer or a group of programmers under an alias Satoshi Nakamoto introduced Bitcoin. Satoshi described it as a ‘peer-to-peer electronic cash system.’ It is completely decentralized, meaning there are no servers involved and no central controlling authority. The concept closely resembles peer-to-peer networks for file sharing.


In 1983, the American cryptographer David Chaum conceived an anonymous cryptographic electronic money called ecash.[7][8] Later, in 1995, he implemented it through Digicash,[9] an early form of cryptographic electronic payments which required user software in order to withdraw notes from a bank and designate specific encrypted keys before it can be sent to a recipient. This allowed the digital currency to be untraceable by the issuing bank, the government, or any third party.

Within a cryptocurrency network, only miners can confirm transactions by solving a cryptographic puzzle. They take transactions, mark them as legitimate and spread them across the network. Afterwards, every node of the network adds it to its database. Once the transaction is confirmed it becomes unforgeable and irreversible and a miner receives a reward, plus the transaction fees.


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.


All of those factors make mining cryptocurrencies an extremely competitive arms race that rewards early adopters. However, depending on where you live, profits made from mining can be subject to taxation and Money Transmitting regulations. In the US, the FinCEN has issued a guidance, according to which mining of cryptocurrencies and exchanging them for flat currencies may be considered money transmitting. This means that miners might need to comply with special laws and regulations dealing with this type of activities.


1) Irreversible: After confirmation, a transaction can‘t be reversed. By nobody. And nobody means nobody. Not you, not your bank, not the president of the United States, not Satoshi, not your miner. Nobody. If you send money, you send it. Period. No one can help you, if you sent your funds to a scammer or if a hacker stole them from your computer. There is no safety net.
Blockchains are secure by design and are an example of a distributed computing system with high Byzantine fault tolerance. Decentralized consensus has therefore been achieved with a blockchain.[29] Blockchains solve the double-spending problem without the need of a trusted authority or central server, assuming no 51% attack (that has worked against several cryptocurrencies).


Hey to all. Since around 2 months, I am with 99bitcoins reading and getting info and I am very happy here, thanks for a good site. For my bad luck I did not check here for a review of coinbase, I would have save a lot of worthless time. To tell the truth, I hope there is a internet god out there and shut them down. I did not know about their support in US, but as I read the first reviews here, it seems they make themselves a pretty bad place there too. I am located in the D.R.,… Read more »
As of May 2018, over 1,800 cryptocurrency specifications existed.[24] Within a cryptocurrency system, the safety, integrity and balance of ledgers is maintained by a community of mutually distrustful parties referred to as miners: who use their computers to help validate and timestamp transactions, adding them to the ledger in accordance with a particular timestamping scheme.[14]




In 2018 Coinbase launched their independant mobile wallet for iOS and Android. The wallet stores the private keys on the user’s device and only they have access to the funds. This brings Coinbase full circle as it started out as a wallet, transitioned to an exchange only (claiming that they are not a wallet) and now they are offering wallet services again.


“In 2 years from now, I believe cryptocurrencies will be gaining legitimacy as a protocol for business transactions, micropayments, and overtaking Western Union as the preferred remittance tool. Regarding business transactions – you’ll see two paths: There will be financial businesses which use it for it’s no fee, nearly-instant ability to move any amount of money around, and there will be those that utilize it for its blockchain technology. Blockchain technology provides the largest benefit with trustless auditing, single source of truth, smart contracts, and color coins.”

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Coinbase is not just a “wallet” for digital money, it is an entire platform that makes it is possible to store, transfer, buy and sell it. The process of signing up is similar to any other website. After logging in, it is possible to choose any national currency in the settings to show the relative rate of Bitcoin. In order to transfer money, it is necessary to add some to the account and then submit the information about the receiver. The latest news concerning Coinbase is that access to its system is now available for 24 countries. Coinbase offers two-factor authentication, exchange on stock markets where all operations are possible without leaving the account, instant confirmation of transfers, and partnership programs which gives users $10 for inviting friends to join the platform.

On May 7, 2019, Binance revealed that it had been the victim of a “large scale security breach” in which hackers had stolen 7,000 Bitcoin worth around U.S.$40 million at the time.[11] Binance CEO Changpeng Zhao said the hackers “used a variety of techniques, including phishing, viruses and other attacks” and structured their transaction “in a way that passed our existing security checks.”[12] Binance halted further withdrawals and deposits but allowed trading to continue. The site pledged to reimburse customers through its secure asset fund.


In February 2019, Coinbase announced that it had acquired "blockchain intelligence platform" Neutrino, an Italy-based startup, for an undisclosed price.[33] The acquisition raised concern among some Coinbase users[34] based on Neutrino founders' connection to the Hacking Team, which has been accused of providing internet surveillance technology to governments with poor human rights records.[35] On March 4, 2019, Coinbase CEO Brian Armstrong said his company "did not properly evaluate" the deal from a due diligence perspective and thus any Neutrino staff who previously worked at Hacking Team "will transition out of Coinbase."[36]


“While it’s still fairly new and unstable relative to the gold standard, cryptocurrency is definitely gaining traction and will most certainly have more normalized uses in the next few years. Right now, in particular, it’s increasing in popularity with the post-election market uncertainty. The key will be in making it easy for large-scale adoption (as with anything involving crypto) including developing safeguards and protections for buyers/investors. I expect that within two years, we’ll be in a place where people can shove their money under the virtual mattress through cryptocurrency, and they’ll know that wherever they go, that money will be there.” – Sarah Granger, Author, and Speaker.