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Re:Coinbase Card by nooyurrsdey on Wednesday October 28, 2020 @05:33PM (#24924366)
Good business move for them. I always chuckle to myself how these things come full circle - this is now back to the old "banking with a credit card" model. The core value of crypto and it's anonymity are now gone, and it's regulated.
Re:Coinbase Card by null0pointer on Thursday October 29, 2020 @01:37AM (#24927598)
Coinbase was never about the original cryptocurrency vision anyway. They always wanted to be the crypto ‘bank’ and be the middleman collecting fees. Even the name ‘Coinbase’ [0] was deliberately chosen to confuse people and make them think that they are somehow core to Bitcoin.

0: In the Bitcoin protocol a transaction which generates new coins and issues them to the miner of a block is called a coinbase transaction.

Re:Coinbase Card by vkou on Thursday October 29, 2020 @03:49AM (#24928170)
Yes, it was quite devious of them to name themselves in a manner that would confuse some tiny fraction of the cryptocurrency geeks [1] that know what a coinbase is, but don't know what Coinbase is.

[1] Which constitute some tiny fraction of the user-base of cryptocurrencies - which is predominantly a gaggle of day-traders, conmen, and the occasional normie who needs to pay a ransomware operator in Belarus.

Re:Coinbase Card by bdcravens on Thursday October 29, 2020 @01:56AM (#24927694)
I don't think anonymity is THE core value; it's more of an added advantage. (I'm looking to the Bitcoin white paper, where anonymity is given one mention, under the tenth heading) The core value is removing custodians (which of course, storing your money at Coinbase or another exchange violates that value)
Re:Coinbase Card by shemnon42 on Thursday October 29, 2020 @12:54PM (#24932527)
Anonymity is part of the censorship resistance. You can't censor something you don't know about. Along the lines of "Can't Be Evil" vs "Don't Be Evil"
Re:Coinbase Card by bouncycastle on Thursday October 29, 2020 @05:43AM (#24928719)
I think that "irreversible payment" is the core value feature. Of course, there's no point if you use Visa.
Re:Coinbase Card by novaleaf on Thursday October 29, 2020 @04:59PM (#24935799)
as the users of this card will soon find out, Debit card payments are pretty much irreversible.
Re:Coinbase Card by john_alan on Wednesday October 28, 2020 @05:51PM (#24924523)
Bitcoin is as traceable as a SWIFT payment. Monero is about the truest to the original cypher punk dream as we have now.
Re:Coinbase Card by brian_cloutier on Wednesday October 28, 2020 @06:14PM (#24924714)
It depends on your trust model. If you believe in fancy cryptography then shielded zcash is even better than monero. Monero keeps increasing the size of the anonymity set as it becomes more clear to them that modern deanonymization techniques are quite good: https://mudit.blog/mixers-are-insufficient/

Though, of course, neither are perfect, we're going to keep finding attacks on these things for a while: https://crypto.stanford.edu/timings/

Re:Coinbase Card by blueprint on Thursday October 29, 2020 @01:15AM (#24927494)
Monero is not a mixer, and actually calculations show a small ring size is usually very sufficient. Read more.
Re:Coinbase Card by brian_cloutier on Thursday October 29, 2020 @09:27PM (#24938169)
If you give me a link I'm happy to "read more" but you're going to have to give me a link or make an argument, I have no interest in going searching for something so likely to be wrong.

Here is an active deanonymization attack [1]:

> We show how an attacker can take advantage of Monero’s Bulletproof protocol, which reduces transaction fees, to flood the network with his own transactions and, consequently, remove mixins from transaction inputs. Assuming an attack timeframe of 12 months, our findings show that an attacker can trace up to 47.63% of the transaction inputs at a cost of just 1,746.53 USD.

Sounds pretty bad to me.

Here's another attack [2]:

> First, about 62% of transaction inputs with one or more mixins are vulnerable to “chain-reaction” analysis — that is, the real input can be deduced by elimination. Second, Monero mixins are sampled in such away that they can be easily distinguished from the real coins by their age distribution; in short, the real input is usually the “newest” input. We estimate that this heuristic can be used to guess the real input with 80 %accuracy over all transactions with 1 or more mixins.

I don't care what "calculations" say, if so many transactions can be deanonymized then those calculations were calculating the wrong thing.

[1] https://eprint.iacr.org/2019/455 [2] https://arxiv.org/pdf/1704.04299/

Re:Coinbase Card by john_alan on Saturday October 31, 2020 @04:00AM (#24949814)
The attacks you link to have been mitigated. I’m an applied cryptographer, I like ZKPs but ZEC is dead in the water for obvious reasons.
Re:Coinbase Card by tootahe45 on Thursday October 29, 2020 @02:17AM (#24927800)
Wasn;t there a day where zcash had only 2 transactions total? these anon coins suffer from their very small user-base.
Re:Coinbase Card by brian_cloutier on Thursday October 29, 2020 @09:35PM (#24938203)
A small user base is absolutely a problem, if there are only so many zcash nodes then traffic analysis becomes very easy.

Though, if there are only a few transactions each day that's not as large of an issue as it sounds; the blockchain still has no linkability between transactions. Active attacks might work but few attackers can pull those off, and no attacker is able to go back in time to deanonymize older transactions (assuming the cryptography holds).

Re:Coinbase Card by jjeaff on Wednesday October 28, 2020 @10:07PM (#24926323)
Bitcoin is not as traceable as a swift payment. You don't have to register your name and address and social security number to transfer bitcoin.

You may be able to trace the addresses that bitcoin is connected to, but you will at some point have to do additional work to investigate ip addresses and hope that they don't all lead to anonymous VPNs ran through a coffee shop wifi before the bitcoin is passed on to someone else.

Re:Coinbase Card by closeparen on Thursday October 29, 2020 @12:35AM (#24927258)
You have to register those things at the fiat currency entry/exit points, and every hop thereafter is public.
Re:Coinbase Card by richardknop on Thursday October 29, 2020 @02:39AM (#24927914)
You can buy bitcoin in cash.
Re:Coinbase Card by shemnon42 on Thursday October 29, 2020 @12:56PM (#24932555)
Only if people re-use bitcoin addresses, or deal with people who re-use addresses. If there is one thing I would change about the protocol it would be to prohibit address reuse. There are techniques like HD wallets that allow you to do this.
Re:Coinbase Card by jhoechtl on Wednesday October 28, 2020 @06:23PM (#24924795)
Sure it is, thats the whole point of it. But nobody knows who I am.
Re:Coinbase Card by jerry1979 on Wednesday October 28, 2020 @10:10PM (#24926340)
I think grin would like word with you.
Re:Coinbase Card by thinkmassive on Thursday October 29, 2020 @12:13AM (#24927133)
Tari is an evolution grin’s mimblewimble chain combined with being merge-mined with monero for increased security. The testnet has been operational for a while, although I don’t follow it closely and haven’t heard anything since they were stress testing it a couple months ago.

https://tarilabs.com/

Re:Coinbase Card by RandomBacon on Wednesday October 28, 2020 @11:52PM (#24927009)
It's been a while since I looked into Grin. My understanding is that it lacks some privacy features compared to Monero, which is what allows Grin to scale better.
Re:Coinbase Card by tromp on Thursday October 29, 2020 @06:13AM (#24928863)
Mimblewimble is about simplicity and elegance which benefit both scalability and privacy. It solves 2 of the 3 major privacy issues (amounts and addresses), while leaving potential to reduce the 3rd (linkability) by making coinjoins trivial (tx aggregation). Monero has much better privacy, but it pays a heavy price in having 20x more chain bloat, and needing to have random access to some info of all spent outputs. It also lacks (scriptless) scripts which makes possible things like payment channels.
Re:Coinbase Card by john_alan on Saturday October 31, 2020 @04:02AM (#24949820)
Interactive protocol, non-private notional.
Re:Coinbase Card by biolurker1 on Thursday October 29, 2020 @02:19AM (#24927810)
Bitcoin is not by design anonymous but only pseudonymus. Blockchain is traceable and transparent.
Re:Coinbase Card by Geee on Wednesday October 28, 2020 @06:07PM (#24924660)
This is just an another payment method on top of Bitcoin. It doesn't have any effect on the properties of the underlying currency.
Re:Coinbase Card by acdha on Wednesday October 28, 2020 @06:18PM (#24924754)
It further highlights how Bitcoin has failed to deliver on any of the heavily advertised changes. Most people do not use Bitcoin and if you talk to to the few who do they almost inevitably are using something like this which keeps all transactions in a real currency.

The reason you should care about that is a pure fiat currency like Bitcoin only has value with other people who agree. Using USD for all real transactions means that merchants continue to have no reason to take on the additional risk and expense of directly accepting it. It lets some speculators cash out but it's not contributing to the growth of the system or give anyone who hasn't already bought in a reason to do so.

Re:Coinbase Card by Geee on Wednesday October 28, 2020 @06:56PM (#24925128)
I fail to see your point. It's much better to keep your money as bitcoin because it appreciates in value vs. fiat currency. With payment solutions like this, you get the benefit of a solid currency and also be able to spend it easily.
Re:Coinbase Card by mundo on Wednesday October 28, 2020 @07:28PM (#24925348)
> because it appreciates in value vs. fiat currency

So did Beanie Babies, until they didn't. But the point of Bitcoin was not supposed to be a vehicle for speculation, it was supposed to be...

well, I've been around HN long enough to know that it's impossible to finish that sentence in a way everyone would agree with. But, remember all those breathlessly optimistic posts and essays from early 2010s about what Bitcoin could be? It seems pretty inarguable that the Bitcoin of 2020 ain't that, and isn't on track to be.

Re:Coinbase Card by sjtindell on Wednesday October 28, 2020 @08:17PM (#24925701)
I think most of the progress is actually being slept on. The other day I was checking in with a buddy who works in the crypto space, and he was describing a whole world I wasn’t aware of where people have been driving forward many of those original ideas - decentralized exchanges, flash loans, literally billions (with a B) of dollars of value being moved through a ton of different systems and use cases. Not the “one currency to rule them all” vision, but people are creating lots of cool things with crypto whether they see a lot of use or not.
Re:Coinbase Card by acdha on Wednesday October 28, 2020 @07:26PM (#24925334)
Bitcoin is a pure fiat currency, which means it only appreciates if you can talk other people into believing it's worth more since it lacks intrinsic value or the inherent demand of a sovereign currency. The theoretical basis for its value is the network of other people who have also bought in but if you're using the credit card network to make transactions in USD you're not giving merchants a reason to accept it directly or seeing any advantages from using Bitcoin.

If you enjoy speculation, that's no more weird than keeping your money in a stamp collection but you don't grow into a real part of the financial system by giving people fewer reasons to care.

Re:Coinbase Card by gvhst on Wednesday October 28, 2020 @09:50PM (#24926227)
I don't think you're using the term Fiat currency properly. Gold is only worth something if other believe it is worth something. It's use in electronics and industry only makes up around 7% of total supply [0].

Yet, gold isn't a fiat asset because its value is anchored to its physical properties. It is finite and cannot be freely created. It doesn't oxidize, is resistant to most acids and other corrosives, and has the highest specific gravity of any naturally occurring element. It is a naturally good store of value because of these properties.

Bitcoin also has underlying properties, but instead they are guaranteed by mathematics and game theory instead of physics. Take that as you will, but both assets are much more solid than Fed Coin (USD) which is effectively backed by the government's commitment to enforce the federal reserve act while trying their best--and failing--to resist printing more and more money to perpetuate an unsustainable system.

[0] - https://www.statista.com/statistics/299609/gold-demand-by-in...

Re:Coinbase Card by acdha on Thursday October 29, 2020 @10:00AM (#24930545)
Here’s the definition of the term I’m using - note that the term does not require government backing:

https://en.m.wikipedia.org/wiki/Fiat_money

The source of your misunderstanding is here:

> Bitcoin also has underlying properties, but instead they are guaranteed by mathematics and game theory instead of physics.

The Bitcoin algorithm has some interesting properties but they don’t have much practical value to balance the enormous inefficiency and, far more important to this topic, that doesn’t make any particular blockchain valuable - anyone who wants those properties can set up their own for free without enriching the current Bitcoin holders. The only reason why you would consider those hashes to be worth paying money for is the community belief that they have a certain value - nobody has any need to use it otherwise. That’s why Bitcoin is an especially pure fiat currency: the community consensus is quite literally the only thing backing it’s valuation. In contrast a currency like the US dollar has curbs on fluctuation not just from much greater usage but also because millions of people receive it from government salaries and purchases or need that currency to pay taxes — unlike Bitcoin, which has value only to the extent that you can find someone else who thinks it’ll be worth more in the future.

Re:Coinbase Card by s0rce on Thursday October 29, 2020 @12:16AM (#24927156)
Other elements have higher specific gravity than gold (iridium, osmium, maybe tungsten and Platinum, id have to check the last two. )
Re:Coinbase Card by michaelt on Thursday October 29, 2020 @06:32AM (#24928974)
Presumably what gvhst means is "It's useful gold is dense, as if there were cheaper denser metals you could create fake gold bars by gold-plating alloys of equal density"

After all, you can already get gold-plated tungsten bars [1] from companies like chinatungsten as 'novelty paperweights' [2] - even though tungsten is fractionally less dense than gold.

As iridium and osmium are traded in very low volumes and toxic/acidic, platinum is more expensive than gold, and tungsten is fractionally lighter, fake gold is seldom undetectable.

[1] https://www.google.com/search?q=tungsten+gold+bar&tbm=isch [2] http://www.paper-weight.cn/products-show.html

Re:Coinbase Card by jkhdigital on Wednesday October 28, 2020 @08:25PM (#24925745)
Bitcoin is digital gold, essentially a reserve currency but not very useful for small daily transactions. All of the criticisms of Bitcoin can be equally leveled against gold, and have been (“barbaric relic” as Bernanke called it). And yet even central banks still hold massive amounts of gold. So I don’t see any reason why Bitcoin can’t fill the same role that gold does in the modern financial system.
Re:Coinbase Card by kypro on Wednesday October 28, 2020 @09:48PM (#24926217)
Unlike gold, Bitcoin has zero intrinsic value and hasn't been used by as currency by civilisations throughout human history.

Central banks would be crazy to hold Bitcoin. If a better technology came along which had mass adoption Bitcoin could be made worthless overnight. Many people predicted this could happen in 2017 during the rise of Ethereum.

Personally I can't ever see bitcoin surpassing the the market cap. of gold.

Re:Coinbase Card by ur-whale on Thursday October 29, 2020 @05:46AM (#24928738)
There is no such thing as "intrinsic value".

There is only the law of supply and demand. Econ 101.

Even the argument that something has intrinsic value because you have a use for it is flawed: how much is a gallon of breathable air worth?

A gallon of air is tremendously useful. How much does it cost ?

Infinite Supply = Zero Value.

There is no such thing as "Intrinsic Value".

Re:Coinbase Card by acdha on Thursday October 29, 2020 @09:48AM (#24930419)
You might want to read this:

https://en.m.wikipedia.org/wiki/Intrinsic_value_(numismatics...

Gold has intrinsic value based on the industrial and jewelry uses: you could lose a lot more over the industrial demand point but it won’t go below that point because people use it for things other than speculation.

In contrast, random hashes have no value outside of a particular community consensus. You can’t do anything with them and the ones in the Bitcoin blockchain have no more inherent value than those in any other network.

Re:Coinbase Card by frank2 on Wednesday October 28, 2020 @08:31PM (#24925784)
>[Bitcoin] only appreciates if you can talk other people into believing it's worth more

I would say the same about gold (though you probably disagree). Gold has some "intrinsic value" (e.g., as a plating on electrical conductors) but would be worth much much less if no one believed that it is a good way to store money.

But perhaps more importantly, Bitcoin differs drastically from most fiat currencies in that its rate of inflation is capped: over 85% of all bitcoin that will ever be created have already been created.

The same BTW cannot be said of gold, which is being mined at an increasing rate:

https://fee.org/media/30406/figure-1_bitcoin_inflation.png

https://fee.org/media/30407/figure-2_inflation_bitcoin_gold....

Re:Coinbase Card by jjdin14 on Wednesday October 28, 2020 @07:17PM (#24925281)
Why does bitcoin appreciate in value vs. fiat currency?
Re:Coinbase Card by dnautics on Wednesday October 28, 2020 @08:10PM (#24925656)
it doesn't have to, but governments can't steal from the poor and give to the rich as effectively if they don't devalue the currency. It's such a mind trick that it gets nearly universal support regardless of if the policymakers is on the left or the right, and everyone who is opposed to it is labeled a kook. If it's gradual enough the increasing divide between the rich and poor will be pointed at other causes like 'capitalism'. Naturally, governments would like to continue such a universally beloved source of revenue, so the state of affairs of bitcoin vs fiat is unlikely to change, and of course bitcoin and similar forms are like to suffer restrictions and limitations imposed on it by governments.

It's also worth noting that the meteoric rises of bitcoin since its inception has very little to do with this fundamental form of cryptocurrency relative appreciation, outside of attracting the kooks who want to believe in alternatives.

Re:Coinbase Card by jkhdigital on Wednesday October 28, 2020 @08:17PM (#24925707)
Because it has a rapidly declining stock to flow ratio, which will soon be even lower than gold. It will be the hardest form of money ever devised.
Re:Coinbase Card by tromp on Thursday October 29, 2020 @06:28AM (#24928951)
This rapidly declining inflation rate is undesirable as it necessarily concentrates wealth in early adopters.

Other coins are even harder in just creating ALL supply in one instant. That makes them both harder and worse.

A constant emission would minimize concentration of wealth yet still have inflation rate going to zero.

Re:Coinbase Card by arthurcolle on Wednesday October 28, 2020 @07:24PM (#24925319)
Because central banks are hyperinflating fiat currencies whereas bitcoin has a fixed supply and a lower velocity of money.
Re:Coinbase Card by acdha on Wednesday October 28, 2020 @07:35PM (#24925406)
Hyperinflation is an economics term with a defined meaning which does not match how you're using it: https://en.wikipedia.org/wiki/Hyperinflation

You're also making the mistake of assuming equal demand: Bitcoin is inherently deflationary but it's also completely voluntary — few people use it and nobody is required to use it. Bitcoin's high variability over the years shows that speculator demand can last for years but there's no lock-in and many competing options. There are a few people who've put large amounts of money into it but statistically almost nobody uses it so there's little defense against a competitor because most people have no sunk cost and most of the percentage who do have only a small holding at risk.

Re:Coinbase Card by arthurcolle on Wednesday October 28, 2020 @08:10PM (#24925658)
https://www.federalreserve.gov/monetarypolicy/bst_recenttren...

USD is being actively and significantly devalued (take a look at the US Dollar Index, as an example), as are most other major fiat currencies. I was using hyperinflation a bit hyperbolically, but the point still stands. One potential interpretation for the the appreciation of bitcoin vs. USD (which, I should add, is the longest its ever been over 10K/btc spot) over the last few weeks is a reaction to the ongoing attempts to jumpstart the various economies of the world that have been put on life support since the start of the pandemic.

Obviously bitcoin and USD don't have equal demand curves, but compare the supply curves: stable vs. arbitrary. If you're comparing two assets, they don't necessarily need to have equivalent instantaneous demand functions - that seems a bit specious.

Re:Coinbase Card by dnautics on Wednesday October 28, 2020 @08:13PM (#24925681)
https://krugman.blogs.nytimes.com/2010/02/13/the-case-for-hi...

> even in the long run, it’s really, really hard to cut nominal wages. Yet when you have very low inflation, getting relative wages right would require that a significant number of workers take wage cuts.

Sir, do you want workers to make a fair wage? We can't have that. You should be supporting inflation.

Re:Coinbase Card by arthurcolle on Wednesday October 28, 2020 @08:56PM (#24925934)
"The growth of the Internet will slow drastically, as the flaw in ‘Metcalfe’s law’ — which states that the number of potential connections in a network is proportional to the square of the number of participants — becomes apparent: most people have nothing to say to each other! By 2005 or so, it will become clear that the Internet’s impact on the economy has been no greater than the fax machine’s."

- Paul Krugman, visionary & scholar

Re:Coinbase Card by Kbelicius on Thursday October 29, 2020 @03:10AM (#24928037)
And how does that refute what he says about inflation and deflation?
Re:Coinbase Card by Geee on Wednesday October 28, 2020 @08:11PM (#24925666)
Because it is better money, and it's more desirable to own. There isn't a simple answer on why it's better money.

Here's a long answer to the question: https://medium.com/@danhedl/planting-bitcoin-sound-money-72e...

Re:Coinbase Card by beaner on Wednesday October 28, 2020 @06:49PM (#24925075)
The core value of crypto and its anonymity are not gone, you simply have the same old option of not utilizing them, in a new package.

If you want those things, go ahead and use them. Coinbase Card isn't stopping you.