Bitcoin's $137k Jackpot • Hacker News Board

Re: Bitcoin's $137k Jackpot

#121

Post by pbhjpbhj » Sat, Apr 30, 2016, 10:01 AM UTC

fiatmoney wrote: post #107

derefr wrote: post #96

Earlier quoted context omitted.

Coming from a perspective of competitive multiplayer game networking, that seems insane. You can't trust the client. An ideal stock exchange, I'd think, would include the same sort of logic as a payment processor: blocking any orders that seem to be "not the sort of order this client would make", to prevent e.g. orders being executed by people who have illegitimately gained access to the account. Of course, these typ…

Multiplayer games are a completely different genre than a professional-level API like a stock exchange. You absolutely must trust that a client's business logic is sound; as long as their credentials validate it's simply out of scope for you to do anything other than explicitly execute their instructions, because that's how the traders make money. "Trust the client" doesn't mean state, it means actions - the equivale…

> the equivalent reasoning in a game would be disallowing the player from "playing badly", which is nonsensical //

Self and team damage is often turned off (on games I've played, I'm not really a big gamer). That would seem to correspond to blocking a sell order that represents more shares than you could possibly have?

Re: Bitcoin's $137k Jackpot

#122

Post by tdebroc » Sat, Apr 30, 2016, 10:05 AM UTC

Intersting explanation: http://bitcoin.stackexchange.com/questions/35986/are-the-hug...

Re: Bitcoin's $137k Jackpot

#123

Post by Nilzor » Sat, Apr 30, 2016, 10:36 AM UTC

fiatmoney wrote: post #107

derefr wrote: post #96

Earlier quoted context omitted.

Coming from a perspective of competitive multiplayer game networking, that seems insane. You can't trust the client. An ideal stock exchange, I'd think, would include the same sort of logic as a payment processor: blocking any orders that seem to be "not the sort of order this client would make", to prevent e.g. orders being executed by people who have illegitimately gained access to the account. Of course, these typ…

Multiplayer games are a completely different genre than a professional-level API like a stock exchange. You absolutely must trust that a client's business logic is sound; as long as their credentials validate it's simply out of scope for you to do anything other than explicitly execute their instructions, because that's how the traders make money. "Trust the client" doesn't mean state, it means actions - the equivale…

.. Or sending the action "deal 1000 damage" when the maximum damage any weapon can do is 5

Re: Bitcoin's $137k Jackpot

#124

Post by pbhjpbhj » Sat, Apr 30, 2016, 10:51 AM UTC

Matthias247 wrote: post #56

jameshart wrote: post #54

Earlier quoted context omitted.

The transaction value is the same either way - 610,000 Yen.

But it should be able to check the current share value and then display a warning that this would be massive loss.

It's more nuanced than that though isn't it - you can sell shares at a loss to push the market so you can buy and profit off the rebound (ie go short)? Kinda like losing your queen in chess in order to check-mate your opponent.

Re: Bitcoin's $137k Jackpot

#125

Post by seanalltogether » Sat, Apr 30, 2016, 11:08 AM UTC

Wouldn't sending a transaction directly to the miner be more reliable then trying to hide it in the fee? If the goal is to hide your money in the high volume of BTC that a big name miner processes per day, why not just send it straight to their wallet?

From an investigators perspective there is no difference between the two scenarios.

1. Miner A has received 500 BTC from Suspect B over the past year and may be laundering it.

2. Miner A has processed 500 BTC in transaction fees from Suspect B over the past year and may be laundering it.

Re: Bitcoin's $137k Jackpot

#126

Post by drcross » Sat, Apr 30, 2016, 11:09 AM UTC

felipeerias wrote: post #118

wimagguc wrote: post #114

Earlier quoted context omitted.

All types of costly mistakes happen in non-bitcoin land too: Deutsche Bank accidentally transfers $6bn to hedge fund client ( http://www.theguardian.com/business/2015/oct/20/deutsche-ban... ) ...as long as humans are involved in transactions (by writing software if anything), human errors seem to be bound to happen.

The diference with Bitcoin-land is right there in the article: "and recovered one day later".

Miners will typically return obviously erroneous transactions to keep bitcoin users in good faith. It's happened numerous times, including this week.

Re: Bitcoin's $137k Jackpot

#127

Post by Rexxar » Sat, Apr 30, 2016, 11:28 AM UTC

pbhjpbhj wrote: post #124

Matthias247 wrote: post #56

Earlier quoted context omitted.

But it should be able to check the current share value and then display a warning that this would be massive loss.

It's more nuanced than that though isn't it - you can sell shares at a loss to push the market so you can buy and profit off the rebound (ie go short)? Kinda like losing your queen in chess in order to check-mate your opponent.

This is market manipulation and it's illegal nearly everywhere.

Re: Bitcoin's $137k Jackpot

#128

Post by speeder » Sat, Apr 30, 2016, 12:05 PM UTC

Houshalter wrote: post #112

gertef wrote: post #41

Earlier quoted context omitted.

unusual, like paying 1 billion times over recent prices?

Yes of course. I'm just saying that usually these systems are badly designed, and recognizing errors correctly is a surprisingly hard problem. In the medical world, many people have been killed by mistakes in prescriptions, despite everything going through computers and multiple humans checking it. The problem was that the machines were too sensitive to mistakes and trained the humans to ignore warnings. They also di…

My mother use computers all day, and also hates them and think they are illogical.

In a way she is correct, I saw her many times freaking out at a dialog box and calling me to "fix it", and it was just some absolutely useless "warning", but I also saw her many times clicking "ok" on a important message without reading and then wondering why things broke.

Re: Bitcoin's $137k Jackpot

#129

Post by harryh » Sat, Apr 30, 2016, 1:27 PM UTC

Nilzor wrote: post #123

fiatmoney wrote: post #107

Earlier quoted context omitted.

Multiplayer games are a completely different genre than a professional-level API like a stock exchange. You absolutely must trust that a client's business logic is sound; as long as their credentials validate it's simply out of scope for you to do anything other than explicitly execute their instructions, because that's how the traders make money. "Trust the client" doesn't mean state, it means actions - the equivale…

.. Or sending the action "deal 1000 damage" when the maximum damage any weapon can do is 5

You can't send an action "deal 1000 damage." The client says "shoot in that direction" the server determines what damage, if any, occurs.

Re: Bitcoin's $137k Jackpot

#130

Post by CydeWeys » Sat, Apr 30, 2016, 1:37 PM UTC

mnx wrote: post #120

CydeWeys wrote: post #82

Earlier quoted context omitted.

I don't understand your objection. The mechanism I explained works to launder and obscure the auditable trail of Bitcoin. All I figure is that you're pointing out some there is some risk inherent in the mining pool simply walking away with the money. OK, sure. There's lots of trust involved in the Bitcoin ecosystem. Every time I buy something on the Internet with Bitcoin I'm trusting the retailer to send me what I or…

Which... they historically are not that unlikely to do.

Well you are laundering money (which is likely illegal depending on your reason for doing so), so it'd be unreasonable not to expect there to be some risk. You're just trading off risk from government for risk from mining pool. But if you do the laundering over a series of transactions spread out in time, you are limiting your potential losses. Say you do it in fifty blocks over a week -- if the miner betrays you your maximum loss is 2%. If you don't tell the miner how much you're laundering through them (they'll just know when you are finished), and you give them an acceptable cut (say, 3%), it would be in their vested interest not to betray you because the expected value of more laundering from you is greater than what they could make by eating any one given attempt.

Also, if they are doing laundering as a service, then trust in them is very important, and screwing over one customer at the cost of potentially losing all future customers is not worth it. For instance, let's say I'm selling $5K of Bitcoin. I'm not worried too much that any given exchange is going to screw me over and eat it, because the big exchanges are doing many millions of dollars in business a day, and stand to lose a lot more from a hit to their reputation from stealing from me than they do to gain from eating my money. The only worry is if an entire exchange goes down (a la MtGox), but you can minimize that risk by not keeping money in an exchange.