Virtual-Currency Craze Spawns Bitcoin Wannabes
online.wsj.com
online.wsj.com
http://themisescircle.org/blog/2013/08/22/the-problem-with-a...
The current implementation works pretty well, but other currencies have other advantages. Litecoin, for example, is designed to be mined on more commodity CPUs than GPUs, and has an algorithm specifically designed to deter faster GPU processing. Meanwhile, WorldCoin (WDC) is optimized for faster transfer times.
I don't know the ultimate long-term value on the former, but WorldCoin's advantage is pretty big, as currently BitCoin is too slow in transfer without slowing up the line to purchase a cup of coffee, for example.
It's possible that other currencies come out mitigating more of BitCoin's deficiencies, or maybe BitCoin can be altered in such a way that its shortcomings can be ameliorated, or maybe they aren't really so painful that they're actually a problem that needs a solution. I dunno.
Either way, I'd be surprised if the first-mover becomes the most entrenched permanently.
That's not exactly true. The transfer is immediate. The verification that ensures you aren't the victim of double-spend fraud takes an average of 5 minutes (during which they are waiting for their coffee). The transaction will show up as unverified on the blockchain even sooner than that, during which a future merchant could choose to not accept payment until the previous payment clears.
Even if they were successful once, the merchant could choose not to sell to them again. Considering the merchant charges on a credit card vs. the low transaction fees of Bitcoin, I would be surprised if Bitcoin didn't come way ahead in this scenario.
In practice you may find that your starbucks coffee will take 10 minutes to buy with a newly created wallet, but comes in immediately when paid with a wallet that you've been using for a while (so it has a 'reputation').
1. Submit transaction A to miners
2. Submit another transaction B (spending the same coins as A) to the vulnerable merchant
3. This is the really hard part: make sure that the merchant doesn't know about transaction A until you got your purchase and ran away.
If the merchant has good network connectivity, it is very, very hard to perform this attack successfully, certainly not something that would be done to get a free newspaper or coffee.
I just dug up an interesting and relevant bit of history. Here is, to my knowledge, the very first response, ever, to the original bitcoin proposal on the cryptography mailing list:
http://www.mail-archive.com/cryptography@metzdowd.com/msg099...
"For transferable proof of work tokens to have value, they must have monetary value. To have monetary value, they must be transferred within a very large network - for example a file trading network akin to bittorrent.
To detect and reject a double spending event in a timely manner, one must have most past transactions of the coins in the transaction, which, naively implemented, requires each peer to have most past transactions, or most past transactions that occurred recently. If hundreds of millions of people are doing transactions, that is a lot of bandwidth - each must know all, or a substantial part thereof."
So it appears the timeliness of verification on a large scale was possibly the very first concern ever voiced about bitcoin.
One confirmation takes an average of 10 minutes.
Exhibit A: HTML
Exhibit B: SMTP
Exhibit C: IPv4
If something kinda sucks, but kinda works pretty well, chances are that we'll still be arguing over it in ~10 years.
Heh. That was their goal, but it didn't work. Then they redefined Litecoin as GPU-friendly and ASIC-hard. Do we believe they're right this time?