Greedy developers want to call off Bitcoin Mass adoption - long term down trend?

[thezerg]

Sure accepting zero-conf has a few problems.  But its a LOT safer then using a string of letters and numbers that any other individual can also use (credit card).  

Large merchants could accept cheap zero conf if they have a relationship with a significant amount of the mining resources:
Don't replace TXes coming from me.  Forward but flag as illegal double spend attempts (and notify me).  This makes it likely you can refuse service instantly or if it becomes a problem arrest the guy right there.

Given mining pools this relationship would not be hard.  Or the merchant makes his own pool.

If the double-spender was in collusion with a significant fraction (say X%) of the hashing power, and those miners were configured to NOT forward his TX then the double-spender would have X% likelihood of a successful double spend.  

That's a lot of work for a 1% (say) chance for a free $5 coffee and BTW never show your face at that store again :-).


So in practice we are fine for small brick and mortar payments.  But it may be a problem for $100+ brick and mortar txns.

[melvster]

Sure accepting zero-conf has a few problems.  But its a LOT safer then using a string of letters and numbers that any other individual can also use (credit card).  

Large merchants could accept cheap zero conf if they have a relationship with a significant amount of the mining resources:
Don't replace TXes coming from me.  Forward but flag as illegal double spend attempts (and notify me).  This makes it likely you can refuse service instantly or if it becomes a problem arrest the guy right there.

Given mining pools this relationship would not be hard.  Or the merchant makes his own pool.

If the double-spender was in collusion with a significant fraction (say X%) of the hashing power, and those miners were configured to NOT forward his TX then the double-spender would have X% likelihood of a successful double spend.  

That's a lot of work for a 1% (say) chance for a free $5 coffee and BTW never show your face at that store again :-).


So in practice we are fine for small brick and mortar payments.  But it may be a problem for $100+ brick and mortar txns.

+1

Cash is not safe.  I read that about 1% of all cash is counterfeit.  But we dont spend ten minutes checking cash for forgery in all instances. 

[dandirk]

None of this is really new... zero confs are probably more secure then checks back in the day when there wasn't any way to confirm the account/amount like they can do today.  Heck remember credit cards with that mechanical carbon/copy form and slider thingy...  The vendor had NO clue if the credit was worth anything, neither with checks...

I find it sort of amusing that BTC is basically this generations version of a check, slow as hell (in relation to technology today).  Back in the day and even today, checks are delayed by days to confirm funds.

How many people use paper checks?  A lot less then there used to be.  I wonder if the privacy aspect of btc is so important to go backwards in usefulness especially when every other option is almost instant.

Basically people will have to trust btc as much as they did with credit cards and checks 15 years ago.

I assume what will happen is that banks or services will offer some sort of trusted account network... like PayPal or something where you BTC in that service is considered trusted for faster transactions.  The cost of this obviously is the privacy aspect of BTC... Just the same as with checks when you had to have your DL on the check and show ID...

[BitcoinAshley]

"All I can say is, this is bitcoin... I don't trust it until I see six confirmations"

Lol @ people who think zero-conf transactions should be regularly used and considered safe. Haven't we been telling people for ages that they aren't safe? But we still have the whiners...

For things like candy machines and cigarettes and petrol and pizza delivery and starbucks $8 lattes and tiny purchases at vendor locations, there are a hundred great ideas for user-friendly services or protocols layered on top of bitcoin that would allow for instantaneous transactions that are SAFE. Use your brain instead of assuming one rigid solution and then whining about centralization or something. The bitcoin protocol simply does not allow for safe zero-conf transactions. Security needs to be robust and if a bunch of idiots trick themselves into thinking zero-conf is safe, bitcoin is not safe.

Relying on zero-conf transactions and whining when someone actually writes a patch to point out that they are not safe, well. Bitcoin isn't for the faint of heart.

Zero-conf transactions are not safe.

Zero-conf transactions are not safe.

Does anyone not understand this yet?

We keep saying over and over again to stop accepting zero-conf transactions, but people do it anyway because it seems secure. It's a very dangerous situation because the security of zero-conf transactions can change overnight simply by some fraction of the hashing power implementing that exact change.

[Zaih]

This is legitimately a terrible idea. Seriously stupid.

I'm sure there's perfectly good logic behind it, but it doesn't change the fact it's bad news.

I'm sure developers will find sufficient ways to get around this however, it surely can't be that hard, right?

[johnyj]

Bitcoin's main advantage over traditional payment network is it's low fee and international reach, not instant payment. A merchant could price all the risk in 0 confirmation payment in his pricing

[amencon]

Zero-conf transactions are not safe.

I don't think the argument is whether zero-conf transactions are safe or not, but if in certain use cases they are safe enough.

As far as I understand it, for cheap transactions the theory goes that it is too costly to make double spending worth it, not that they couldn't be done.  Much like bitcoin itself isn't "safe" from a prolonged 51% since it's theoretically possible someone could buy that much hashing power, more that the incentive doesn't outweigh the cost.

If merchants priced in double spends as fees or increased costs as johnyj says, I could really only see a problem if, to remain profitable, merchants would have to raise rates enough that bitcoins were cost prohibitive when compared to other methods of payment, however I haven't heard anyone make an argument that this is or would be the case.