One Ring Signature To Rule Them All
How blockchains can store your data, without knowing who you are
Article also available on Mirror
The word “Blockchain” is being used about as much as “Adkins” or “Y2K” was 15 years ago, but unlike a cheatcode for losing weight or the fear of tech-financial armageddon, not many people seem very interested in finding out what a blockchain actually is. And why would they? If the days of making a quick cash grab from buying crypto are over, what does blockchain have to do with them?
Now, before all the blockchain enthusiasts jump down to the comments to eagerly explain why exactly blockchain will revolutionize the world, save your energy. The average person isn’t that interested in a decentralized, anarchist, censor-free internet. So, what might they be interested in? What can blockchains offer them? And what has, until this point, proved to be difficult when using a public ledger? Let’s start with the good, the bad, and then how to get past the ugly.
The Good
The good is very good. Blockchains provide a public ledger, something that could be compared to a stone holding records, that everyone can see and everyone can verify. This makes contracts and transparency super awesome. For the first time, we can have contracts that are enforced without enforcers, accountability without bureaucracy, and data that can’t be destroyed or altered without permission. It’s the Wild West of the internet! Except…
In the new Information Age, one of the biggest concerns is exactly that we don’t want all of our information to be public, persistently existing in the Ether until the days of Ragnarok. Sure, we might be able to have privacy when it comes to using Monero to buy LSD on a Silk Road clone (I’ve only heard about this from friends, of course), but when it comes to other information, the public ledger might be our greatest enemy. Someone could figure out your medical records on a public ledger, or who you voted for (gods forbid, if you voted for the person everyone in your community told you not to vote for). So, while blockchains are amazing in some ways, how do we get past this icky-side?
How to get past The Ugly
The most promising method to get past this is known as a Ring Signature. I won’t get into the heavy-duty math involved, though you can read all about it here. The basic concept is that it puts all the public keys into a group, adding each private one in a “ring” formation. The result of this means a person can use their public key in a group of public keys, without anyone knowing which public key belongs to who. In other words, this means you can vote in a decentralized, all-party verifiable election, and no one will know who you voted for. With new additions being made to Ring Signatures, it can also prevent the same private key from being used in a group more than once: meaning you can’t vote more than once. You could even do this in a polling booth, showing authorities your identification, and yet still no one will be able to find out how you voted (well, unless they peak over your shoulder). You might say “Oh, I’m not concerned about that, I trust our election system.” And even if you do feel this way, there are many places in the world where independently-verified elections just are not possible, or else very expensive and difficult. This could change this, and remove the biggest challenge elections face forever.
Just a bit more detail
Ring Signatures contain mathematical functions that can be computed using a public key. The private key gives a specific input which affects the public key’s output. The signature contains a list of values, with each value being set to the previous value’s function, the private key containing the ability to “close the loop” (hence, Ring Signature), causing the last value to equal the function of the first. Due to this ring, it is verifiable, or else the loop would not be closed, but it is impossible to tell which private key belongs to which public one. With Linkable Ring Signatures, a private key cannot be used more than once. They can now be implemented on Ethereum, and are already used for Monero.
Conclusion
I’ve been told to close blog posts with a conclusion of some kind, so I’ll give it a Go. 1. Blockchains offer great potential for solving some of our greatest coordination failures. 2. They kind of suck if everyone knows what you’re doing all the time. 3. Though it may not be One Solution To Rule Them All, Ring Signatures provide a very promising method of solving some of the biggest hurtles blockchain protocols currently face. 4. Voting, medical records, and many other applications are possible with a decentralized blockchain that utilizes this new form of signing. 5. And they also look really cool, too.
