Topic: [ANN] Reality Keys: An oracle letting you use external state in transactions - page 3. (Read 7751 times)

Could you explain why you've chosen to publish keys rather than using Mike Hearn's algorithm? I have to admit I find the writeup on the Bitcoin wiki confusing, but maybe you could shed some light on it.

One advantage your approach appears to have is that you are not signing a transaction, in fact you need not even know what transaction it might unlock if it used P2SH or hasn't been published. This could limit temptations or threats you might be exposed to, including legal liability.

A potential complication is that people could send money to the published public keys. What would you do with such funds?

Great stuff! I wonder if you guys could use a blockchain-based trusted timestamping service like virtual-notary.org, proofofexistence.com etc to keep a record of events that you've registered, together with the public keys for the two possible outcomes. Once you've published the correct private key for an event, you could have that fact notarised too. In this way you could build up a reliability record that people can check.

Thanks, I'll take a look at the feeds Reuters can provide and see if there's anything we can use. Some of the commercial feeds provide very good quality data, but I'm a little bit nervous about tripping over something in their Terms of Service, or them stumbling on some of the more mind-blowing implications of what we're doing here and suddenly terminating our access, which could suddenly leave people using keys based on that data SOL.

Great to hear, let us know if there's anything we can do to help.

Right, that's my assumption too. Like I told the Coindesk guys, it's a chicken-and-egg problem where we need a few different parts, and none of them are much use without the others. Anyhow we have to start somewhere, so here's a chicken. It won't cost much to run and we're not depending on it to pay next month's rent, so we're happy to keep it running for as long as it takes for the ecosystem to develop.

Anyhow I was a little bit taken aback by the amount of attention the CoinDesk piece got last week. It really does look like there's a lot of interest, and all kinds of potential if we can bring all the pieces together.

Edmund, you have no idea how excited I am about your project. 

I've been working on a project for the last month and a half which uses oracles extensively.  Reality Keys may rapidly accelerate development of my project!

Very interesting.  Even better if you are able to plug into more authorative sources such as Reuters monitor systems.  The quality of the data is obviously very important.

Ha, glad to help!

You know, I'm really excited to see this service pop up - I was expecting to see the software to actually use this stuff get developed first and see people struggle to actually get the important oracle infrastructure developed, but you've done the exact opposite. I will say, don't be surprised if adoption is slow at first, the infrastructure to actually use the oracle for real transactions isn't really there yet. But hang in there and give it time for use-cases to develop; I'm sure they will in the long run.

I'm pleased to announce the release of Reality Keys. We provide information about things happening in the world - everything from exchange rates to election results, drawn from services with public APIs - in a form that can be understood by miners and used to confirm Bitcoin transactions. Our service is a little bit different from the  "external state oracle" Mike Hearn discusses here:
https://en.bitcoin.it/wiki/Contracts
...but we hope people will find it useful for some of the use-cases he describes.

Specifically, you can register an event - "1 USD will be worth more than 1 Euro on Feb 24th", or "Edward Snowden will win the Nobel Peace Prize by the end of 2015" - and we give you a pair of public keys, one representing the event happening and another representing it not happening. When that date comes around, we'll query the relevant API to find out whether the thing happened or not and release the private key for the public key that corresponds to the outcome. You can then use those keys in multi-sig crypto-currency transactions in the same way you might use a normal signature.

Currently our data comes from Coindesk (Bitcoin exchange rates vs USD), the ECB (exchange rates of legacy currencies), blockchain.info (Bitcoin address balances) and Freebase (everything in the known universe). Let us know if anyone has anything else they'd like us to monitor; In principle we can handle any API you can point us to as long as it has reasonably permissive Terms of Service and some other feasible way to double-check the information we get from the it in the event that it misbehaves. Please be patient with us if we run into performance issues over the next week or two, or if you manage to turn up some patterns of information in Freebase that we hadn't bargained for.

Our service can be used free of charge, to the extent that you are happy to abide by the automated results we pull from our data sources. However, we also allow you to pay a fee, currently 10 mBTC, to have a human check what happened, in the event that you think the API-generated result was wrong. For exchange rates etc we expect that this facility will hardly ever be used, but it may be useful for if you've made - say - a high-rolling bet on an election result, and the loser tries to rip you off by tinkering with one of the community-curated databases that feed into Freebase.

Note that although we think this will be useful for people making all kinds of Bitcoin contracts, including some of the scenarios described in this CoinDesk piece, we aren't going to do anything to help you find someone to make a contract with or actually create the transaction. Obviously our service isn't much use without being able to do these things one way or another, but software for brokering advanced transactions and (potentially p2p) order books are big projects in themselves, which we hope to leave to the people already working on them, who are generally much smarter than us. We've provided a simple, authentication-free API that you can use to register facts, grab the resulting keys and check on their status. Please don't hesitate to get in touch if there's anything we can do to make our service more useful to you.

Also note that, since we only issue keys to say what happened in the world rather than actually taking part in contracts, we're not in a position to confirm the legality of using our keys to create any particular contract in your particular jurisdiction. Please make sure you check these things yourself and abide by your local laws and regulations.

Finally, special thanks to a couple of people on these forums: Mike Hearn, who has long been blowing everybody's minds on all things contract-related, and Peter Todd, who seems to come out with at least one important bitcoin-related insight every weekend, and two on bank holidays.