 DTA asks, what criteria would you suggest to determine whether a task or function is better executed on a permissionless blockchain as compared to a centralized system? Do you think permissioned blockchains are real blockchains? Do they have a role too? This is an interesting question, DTA. First of all, permissioned blockchains are blockchains. Sure, what they're not is open blockchains or permissionless blockchains. They are blockchains. They just don't have any of the interesting features that I think we find in open blockchains. One thing to understand is that some of the features that people ascribe to blockchains are actually not features of blockchains. They are features of open decentralized blockchains. For example, immutability, the ability to record something and have a guarantee that it cannot be changed even if all of the verifiers are being coerced into changing it. Bitcoin, for example, is a system that provides that immutability guarantee. Even if 100% of the miners wanted to change the blockchain and were being coerced to do so, they would still have to expend the proof-of-work energy in order to do that, or risk getting their blocks invalidated by the rest of the system. There is no shortcut to that. They still have to expend the energy. Proof-of-work creates immutability in that particular case, and the decentralized nature of the consensus algorithm makes it immutable. If you have a system of federated signers, a permissioned blockchain, or decentralized ledger technology, as it is sometimes called, or private blockchain, as it is sometimes called, then maybe you have 16 signers. These 16 signers are members of a coalition that are part of the participants in this group. Let's say it is 16 of the largest participants in a stock market or in a bank transfer network, and they are all federated signing. Well, you serve a subpoena to all 16 of them, and you tell them, you must change this transaction and make sure it never happens. So, you see, this transaction back in January was paid to WikiLeaks, and we don't like that. So, here is a court order that says that transaction never happened. Please amend your blockchain. Well, the federated signers can do that, and if they can do that, then under the law, they must do that, so it is no longer immutable. It is no longer censorship-resistant. It is no longer neutral. It is no longer borderless, because they are subject to the jurisdiction, these federated signers, of one state, or whichever states they are in, so they can't open it up. Of course, it is no longer permissionless, because they have to vet every participant. So, this is the issue here. Once you take out the decentralized nature of validation, the consensus algorithm, then a lot of the things you think blockchains do, which is give you censorship-resistant, neutral, permissionless, immutable transactions, go away. What you have is a distributed database that allows you to record transactions if the federated signers want to allow it. You have something that is not immutable, censorship-resistant, neutral, borderless, or permissionless anymore. Is that thing useful? That is an interesting question, because it depends on what you are trying to achieve. If the application you are trying to achieve doesn't need censorship-resistance or neutrality or borderless access or immutability, then yes, maybe it is useful. Of course, then you have the other challenge, which is that in an environment like that, a federated signing, you have the fundamental problem that the federated signers are usually competitors. Therefore, in any such environment, they are going to try to tweak the system to give each one of them maximum advantage. In a decentralized blockchain, the selfish approach, which is everyone acting purely in their self-interest, is the basis of the game theory that makes it secure, meaning that as long as everybody acts in their best interest, the system is actually fair, predictable, and secure, because those actions lead directly to fairness. That is how proof of work works. For example, it assumes that everyone will act purely in their self-interest in very selfish ways, but because they are constrained by the system, they are forced to operate it securely, because it is in their best interest. In a permission system, however, if the federated participants are all acting in their own self-interest, you have a problem. Because they can be identified, because they can be coerced, and because they have to participate in a collaborative manner, the incentives really get misaligned. You can see this every time you look at an industry trying to create common standards by committee, and they start off with good intentions. Let's make a new standard for how we do financial exchange protocols or whatever. As the participants get together, each one of them has a vision of what will be in their best interest, and they try to add that to the standard. The standard gradually gets more and more and more complex, because there is all of this jockeying for position. In the end, it is not really a standard. It is just a collection of the wish list and kitchen sink, a bike shedding that happened by all of the participants. These standards do not get applied in the real world, because they are too complex and there is too much opportunity for one party to take advantage of another. A classic thing you see in protocol development is where you get all of these big companies together to build a common standard. At the same time that they are sitting down at the table and proposing common aspects to the standard, they are lawyers in the background of filing patents for those same things in order to gain an unfair advantage. This happens all the time. It is why, over decades, the attempts to do common standards in banking continue again and again to collapse. They collapse because, whenever the standard is designed by committee, all of this jockeying for position results in a mess. Theoretically, at least, permissioned blockchains with federated signers based on a common standard would work. They would actually bring the industry together, create more collaboration, allow banks to have essentially faster and more fair networks for doing backend transactions. In practice, they never get there. The reason they never get there is because the squabbling and jockeying for position internally ends up creating either a terrible standard that does not serve anybody's needs, or a standard that nobody uses because they feel they will be at a disadvantage. Because the standard expresses somebody else's interests. We have seen this again and again, most recently with R3, and their efforts to create these standardized financial services blockchains. Again, all of these prototype implementations have not succeeded. We saw this with Internet protocols, too. TCPIP was not the obvious winner. Now, everybody is clear that the Internet is TCPIP, TCPIP is the Internet. But if you look back in the early 90s, the conversation was very different. People said TCPIP is going to be an interesting but edge case of the information superhighway, that will be primarily based on robust enterprise protocols like the ISO and OSI protocols, TP4, for example, and protocols like ATM, protocols like those proposed by IBM and Microsoft and others. This information superhighway would have a small corner, mostly of academics, which would use TCPIP. But the TCPIP wasn't really suitable for enterprise use because it didn't have enough features that the enterprise wanted. Where did we end up? We ended up with the information superhighway being a silly term that people laugh at today. The Internet being TCPIP and only TCPIP, all of the other protocols you've probably never heard of, TP4 and ATM and the OSI stack that were proposed by the telecom companies. You don't run ISDN probably. All of these things went to the wayside. Why? Because in the end, the value came from the open interoperability of a protocol where no one had a distinct advantage. We're going to see the same thing happen with blockchains.