Bitcoin Forum

I think there should be some kind of universal warning system which broadcasts emergency warnings such as the recent blockchain fork.

How it could work:

1) Have a domain setup with simple JSON service with a few simple fields such as, alert status, alert message, more info link
2) A small select/vetted number of developers and community members would have access to update the status/alert message
3) Bitcoin client software could be coded to the check the warning system and show alerts.

Something like this:
http://i50.tinypic.com/1053xg1.jpg

For example I use Electrum, I received some bitcoins right around the time of the fork, in Electrum it was showing 6+ confirms, so I transferred out some money to the sender.  When I later heard about the fork and potential double spends on transactions with less than 11+ confirms I just about shit myself.  Luckily there was no double spend, but we can't really expect all users, merchants etc...to be constantly monitoring the forums and IRC to know whether they should trust the confirmed transactions in their wallets.

I think the main argument against this might be "What if the alert system got hacked or abused"....well at the end of the day what's the worst that could happen?  Users see a "See sexy p0rn click here" type of message for a few hours?  But if you compare this risk, to the risk of users being totally unaware of major network issue; I'd prefer to have the warning system.

If I get some feed back that people think this could be a good idea, and some devs would consider integrating it I'd be happy to setup and maintain the warning service.

Just propagate the message broadcasted on the Bitcoin network to lightweight clients too (Bitcoin-qt displayed a warning about the network split when it happened).

I suppose it's only a matter of adding the public key used for such messages to Electrum and add support for these broadcasts in the Electrum<->Electrum server protocol.

well it took some time until gavin did it and another ~15 until ppl saw it

If the message is broadcast across the bitcoin network itself then doesn't it run the risk that if the network is misbehaving then the message may never arrive?

It's kind of like twitter tweeting that their network is down...(ie no one is going to see the tweet anyway)?

There is. See https://en.bitcoin.it/wiki/Alerts

However you need to be running a Bitcoin client that will accept and publish the alert. Since not everyone all the time is running such a client I just implemented an email relay service:

https://en.bitcoin.it/wiki/Alerts_mailing_list

Regards,
Gary

nice service ;)

There is a slight problem with showing the Bitcoin-QT alerts in lightweight clients as you will often get a message like 'URGENT: Upgrade required' but of course that may not be actionable to the lightweight client user.

If there was a tag for 'network' alerts versus 'bitcoind' alerts we could distinguish them. It could just be a Twitter style tag that was guaranteed to be only in the 'network' alerts. '#URGENT' would probably do it - if you are broadcasting an alert to absolutely everybody it is almost certainly time critical.

The alerts are available in bitcoinj for instance but so far they aren't shown in MultiBit as they can be quite confusing to the end user.