This means parking meters, vending machines, laundromats, etc. can receive bitcoin payments without an internet connection. That is actually really cool.
Also, things like DVB tuners are not exactly cheap enough to be integrated into many devices (though FM receivers, which may be used in the future, are).
Are there any such chips other than the Broadcom chip that was announced last year?
[1] http://www.broadcom.com/press/release.php?id=s736006 [2] http://www.digitaltvnews.net/?p=24266
If the payment terminal used an SPV-like technology, the attacker would have to have a tremendous amount of computing power. This attack is not feasible, especially considering the relatively small reward of fooling an ATM or a parking meter.
In this case, there's a single communications channel that could be spoofed by anyone with a transmitter powerful enough to drown out the legitimate signal.
You could stop sending new blocks, but that would alarm the endpoint because it will be stuck at block 100 (in our example).
The Proof-of-work scheme is pretty innovative.
As noted in the article (under the "technology" page), signing is planned but not yet implemented.
> Also, things like DVB tuners are not exactly cheap enough to be integrated into many devices (though FM receivers, which may be used in the future, are).
What kind of devices are you thinking of? It seems to me that the most useful applications of this system would be for vending machines. A $10 DVB-T demodulator (at scale they can be had much cheaper than that) is a rounding error in the cost of those devices.
Cryptocurrency's design targeted the libertarian dystopia related to the interdependent nature (and potential abuse) of governments and their currencies. Given that the dystopian context doesn't exist strongly enough, other options will continue to have advantages within the current context.
You're more likely to show benefits with this when you can provide oppressed peoples' crypto-wallets with balances that can be converted into subversive tools. This, of course, will gain more of certain types of attention than a young currency could want.
Paying for parking is easy as it is. Same with paying to wash clothes. If you can't get cities and coin-op owners to upgrade to card swipe technology, good luck with selling them on immature digi-currencies.
Cryptocurrency needs to think less about catching up in various verticals and more on creating the killer value app... and the problem is nobody is seeing big $'s around the things that today's currency transfer technology has trouble with. We're on the cusp of IoT. Internetless internet-based currency?