2 CommentsHere’s what happened this week in Bitcoin in 99 seconds.
Some disappointing news came out when Samsung revealed that the hardware wallet on their newly-released S10 phone will only support Ethereum, ERC20 tokens, and four dApps. It appears that Samsung will upgrade the wallet to also support Bitcoin and further altcoins in the future.
Chinese ASIC producer, Canaan Creative, has raised several hundred million Dollars in funding. The firm’s valuation is now placed at over $1 billion. Although details are scarce, it is assumed the majority of the investment will be put towards the production of new ASIC miners.
Calgary police are seeking to identify 4 suspects who stole over $200,000 Canadian Dollars’ worth of BTC from Bitcoin ATMs. The suspects used double spend attacks to defraud BTMs across 7 Canadian cities.
Former Mt. Gox CEO, Mark Karpeles was handed a two and a half year suspended sentence by a Japanese court. Karpeles was convicted of tampering with financial records but exonerated of embezzlement charges. Karpeles will remain outside prison unless he violates the terms of his probation.
And finally, popular stablecoin Tether has updated its Terms of Service, once again raising questions over its dollar peg. Social media users noticed that they had removed the previous claims that Tether was fully backed by US Dollars. Instead, the site currently says reserves may include other assets and receivables from loans made by Tether to third parties.
That’s what happened this week in Bitcoin. See you next week.
I thought the bitcoin solved the double spend problem and that’s what made it so revolutionary. How could someone have done a double spend attack?
Hi Louis,
Good question. Bitcoin does indeed solve the double spending problem but in a graded way… You’re probably familiar with transaction confirmations? After you send a transaction, you have to wait a while for a miner to pick it up and include it in a block they mine, right? Once included in a block, it’s impossible to spend those sames coins again (apart from the fairly rare circumstance of a blockchain reorganisation).
The more confirmations you receive on a transaction (in other words, the more blocks are “piled on top” of the original block your transaction was included in) the more secure and permanent your transaction becomes, as the amount of hashpower required to re-org the chain multiplies with each block found.
Now, the reason the guys in Canada were able to scam the BTMs was that these machines paid out before receiving a single confirmation on the blockchain. In other words, as soon as the machines saw the transaction in the mempool, they would pay out the cash… At least, that is my understanding of how this occurred and I don’t really see how it could be otherwise.
This is why Bitcoin Cash’s reliance on zero-conf (or zero-confirmation transactions) as a way to provide instant transactions and work as an “alternative” to Lightning Network is so flawed – it’s really insecure and anyone who knows how can double-spend an unconfirmed transaction with minimal effort. I mention this because the https://doublespend.cash/ site displays a list of such double-spends on unconfirmed transactions in case you want to dig into this topic using real data.