So, every x days, every user of the currency in the country has to upgrade their software, because the government has blocked the protocol, so they need new software that in essence uses a different protocol???
If using this currency is that inconvenient, people will just go back to using credit cards and Paypal.
I don't have to download a new copy of uTorrent if I decide to use different ports.
The client could probably just check periodically for a signed message from a central server (or a broadcast on the network itself) with instructions to currently operate on the network.
This isn't really a big deal or usability issue that I can see.
I see I've been modded down. Why? What do you people know that I don't?
It seems to me like I'm asking a simple, obvious question: what is stopping governments from simply shutting down Bitcoin within their physical borders? You think they will not be smart enough to handle a simple port number change?
Regarding the comparison with Bittorrent, my ISP (Comcast) did in fact block and throttle Bittorrent, successfully, until someone sued them. It seem to me Bittorrent is an example of how ISP's can block an application, not an example of them being unable to do so.
"The client could probably just check periodically for a signed message from a central server (or a broadcast on the network itself) with instructions to currently operate on the network." -- why could the ISP not block this, also?
Especially if the software is open source, as Bitcoin is, all the knowledge of the inner workings of the protocol is public knowledge, which makes it impossible to stick in something like "just check periodically for a signed message from a central server (or a broadcast on the network itself) " secretly without governments wanting to block the system knowing about it.
It's fortunate (for Bitcoin) that governments and ISPs generally move at a sloth's pace. If it comes down to an arms race, they can't win more than extremely temporary victories. If they could, they'd have completely stopped filesharing over Bittorrent, IRC, AIM, MSN, Skype, HTTP, email, Usenet, various P2P services like Kazaa and Limewire, ... and so on.
If they start blocking/interfering with the protocol (like Comcast injecting RSTs into suspected torrent connections), you can just encrypt the entire transport layer and randomise the ports. People were configuring their firewalls to drop the falsified RSTs from Comcast.
If they blacklist hostnames, there's a near limitless number of them that can be generated. The client can precalculate a domain and ping it at a given time for instructions the same way botnet clients work. The government can't register/block every possible domain name that will be generated. Another alternative: http://en.wikipedia.org/wiki/Fast_flux There's nothing illegal about having a hostname resolving to an IP.
> Especially if the software is open source, as Bitcoin is, all the knowledge of the inner workings of the protocol is public knowledge
This is also true for GPG, ciphers like AES/Twofish/Serpent, etc. Openness does not necessarily imply weakness.
Weakness from the standpoint of the ability of a network operator to block the protocol? GPG could be blocked quite easily. Email encrypted with GPG declares itself so
I feel upset about being modded down -- I feel I asked a fair question. Governments gain their power from being able to tax and dilute currency. Bitcoin, if it gains traction, will be a direct threat to both. It does not seem realistic to think governments will not fight back, and hard. If I'm right, it means simple tricks like changing ports and changing IP's won't work. You say "The government can't register/block every possible domain name that will be generated." -- maybe they can if they know the algorithm that is being used to generate the domain names? Or maybe they can examine the contents of the packets, so there is no need to block every domain name (or IP in the case of Fast flux). For every change to the protocol to thward getting blocked, the blockers and respond to the change because the protocol is open.
I suppose the "worst case scenario" is that Bitcoin has to be used over a generic VPN protocol, similar to what people do now to get around the Great Firewall Of China. As I understand it, the Chinese government has not blocked the VPN protocols, mostly because few enough of the Chinese people use them -- but if a large percentage of Chinese people started using VPN's, wouldn't the Chinese government start blocking VPN protocols?
Perhaps the Great Firewall Of China is the best example of the capability a government has to control its internet within its physical territory?
Blocking every VPN is something that should eventually fail because large enterprises (Fortune 500 Co) won't stand for it. So I can understand the argument that governments _ultimately_ can't stop Bitcoin or something like it. But it seems to me like they won't give up without a fight.
If using this currency is that inconvenient, people will just go back to using credit cards and Paypal.