Multisignatur-Bitcoin-Wallets als Diebstahlschutz c't ...

Electrum - Simply the best thin Bitcoin client

The best, cutting edge thin Bitcoin wallet.
[link]

BCexchange, the decentralized cryptocurrency exchange for everyone

Subreddit for BCexchange (short for ​Blocks & Chains Decentralized Exchange). B&C Exchange will be an open-source decentralized exchange that completes cryptocurrency trades between users by utilizing multisig signers that compete for blockchain rewards based on their effectiveness and honesty. Trades occur using real cryptocurrencies such as Bitcoin and NuBits.
[link]

SUPERCOIN - Unique Most Advanced Anonymous Trustless Multisig Technology

SUPERCOIN - First P2P Decentralized Trustless Anonymous Coin
[link]

Bitcoin Q&A: How is a Multisig Address Created? | Blockchained.news

submitted by Thornsb to BLOCKCHAINEDNews [link] [comments]

"@Bitstamp Thank-you for being a good steward of the Bitcoin blockchain!" (SegWit + Batching - MultiSig = 52 sat/byte tx fee)

submitted by Bastiat to Bitcoin [link] [comments]

"@Bitstamp Thank-you for being a good steward of the Bitcoin blockchain!" (SegWit + Batching - MultiSig = 52 sat/byte tx fee)

submitted by BitcoinAllBot to BitcoinAll [link] [comments]

Tokyo Bitcoin Hackers Presentations, hosted by wiz, mind blowing stuff! Building wallets, Blockchain analysis and multisig.

Tokyo Bitcoin Hackers Presentations, hosted by wiz, mind blowing stuff! Building wallets, Blockchain analysis and multisig. submitted by leakypat to Bitcoin [link] [comments]

BitcoinShowerthought: A 2 of 2 multisig on a private blockchain running securly in a nuclear silo could be used to secure a Nuclear Arsenal, the same way two keys held be two men are used. /r/Bitcoin

BitcoinShowerthought: A 2 of 2 multisig on a private blockchain running securly in a nuclear silo could be used to secure a Nuclear Arsenal, the same way two keys held be two men are used. /Bitcoin submitted by BitcoinAllBot to BitcoinAll [link] [comments]

Tokyo Bitcoin Hackers Presentations, hosted by wiz, mind blowing stuff! Building wallets, Blockchain analysis and multisig.

Tokyo Bitcoin Hackers Presentations, hosted by wiz, mind blowing stuff! Building wallets, Blockchain analysis and multisig. submitted by moon_drone to BetterBitcoin [link] [comments]

How to safely trade Bitcoin for cash with a stranger?

Hello I'm looking to obtain Bitcoin for cash. I've been refered to a complete stranger who'm I've been told is trustworthy, but how would the transaction work so I know I'm not going to get scammed?
I'm going to propose meeting in a popular coffee shop but aside from that I'm quite clueless about how to safely go about it.
I have a Ledger hardware wallet for storage.
Any help would be greatly appreciated, Many thanks
submitted by lawrencespratt to Bitcoin [link] [comments]

Proposal: The Sia Foundation

Vision Statement

A common sentiment is brewing online; a shared desire for the internet that might have been. After decades of corporate encroachment, you don't need to be a power user to realize that something has gone very wrong.
In the early days of the internet, the future was bright. In that future, when you sent an instant message, it traveled directly to the recipient. When you needed to pay a friend, you announced a transfer of value to their public key. When an app was missing a feature you wanted, you opened up the source code and implemented it. When you took a picture on your phone, it was immediately encrypted and backed up to storage that you controlled. In that future, people would laugh at the idea of having to authenticate themselves to some corporation before doing these things.
What did we get instead? Rather than a network of human-sized communities, we have a handful of enormous commons, each controlled by a faceless corporate entity. Hey user, want to send a message? You can, but we'll store a copy of it indefinitely, unencrypted, for our preference-learning algorithms to pore over; how else could we slap targeted ads on every piece of content you see? Want to pay a friend? You can—in our Monopoly money. Want a new feature? Submit a request to our Support Center and we'll totally maybe think about it. Want to backup a photo? You can—inside our walled garden, which only we (and the NSA, of course) can access. Just be careful what you share, because merely locking you out of your account and deleting all your data is far from the worst thing we could do.
You rationalize this: "MEGACORP would never do such a thing; it would be bad for business." But we all know, at some level, that this state of affairs, this inversion of power, is not merely "unfortunate" or "suboptimal" – No. It is degrading. Even if MEGACORP were purely benevolent, it is degrading that we must ask its permission to talk to our friends; that we must rely on it to safeguard our treasured memories; that our digital lives are completely beholden to those who seek only to extract value from us.
At the root of this issue is the centralization of data. MEGACORP can surveil you—because your emails and video chats flow through their servers. And MEGACORP can control you—because they hold your data hostage. But centralization is a solution to a technical problem: How can we make the user's data accessible from anywhere in the world, on any device? For a long time, no alternative solution to this problem was forthcoming.
Today, thanks to a confluence of established techniques and recent innovations, we have solved the accessibility problem without resorting to centralization. Hashing, encryption, and erasure encoding got us most of the way, but one barrier remained: incentives. How do you incentivize an anonymous stranger to store your data? Earlier protocols like BitTorrent worked around this limitation by relying on altruism, tit-for-tat requirements, or "points" – in other words, nothing you could pay your electric bill with. Finally, in 2009, a solution appeared: Bitcoin. Not long after, Sia was born.
Cryptography has unleashed the latent power of the internet by enabling interactions between mutually-distrustful parties. Sia harnesses this power to turn the cloud storage market into a proper marketplace, where buyers and sellers can transact directly, with no intermediaries, anywhere in the world. No more silos or walled gardens: your data is encrypted, so it can't be spied on, and it's stored on many servers, so no single entity can hold it hostage. Thanks to projects like Sia, the internet is being re-decentralized.
Sia began its life as a startup, which means it has always been subjected to two competing forces: the ideals of its founders, and the profit motive inherent to all businesses. Its founders have taken great pains to never compromise on the former, but this often threatened the company's financial viability. With the establishment of the Sia Foundation, this tension is resolved. The Foundation, freed of the obligation to generate profit, is a pure embodiment of the ideals from which Sia originally sprung.
The goals and responsibilities of the Foundation are numerous: to maintain core Sia protocols and consensus code; to support developers building on top of Sia and its protocols; to promote Sia and facilitate partnerships in other spheres and communities; to ensure that users can easily acquire and safely store siacoins; to develop network scalability solutions; to implement hardforks and lead the community through them; and much more. In a broader sense, its mission is to commoditize data storage, making it cheap, ubiquitous, and accessible to all, without compromising privacy or performance.
Sia is a perfect example of how we can achieve better living through cryptography. We now begin a new chapter in Sia's history. May our stewardship lead it into a bright future.
 

Overview

Today, we are proposing the creation of the Sia Foundation: a new non-profit entity that builds and supports distributed cloud storage infrastructure, with a specific focus on the Sia storage platform. What follows is an informal overview of the Sia Foundation, covering two major topics: how the Foundation will be funded, and what its funds will be used for.

Organizational Structure

The Sia Foundation will be structured as a non-profit entity incorporated in the United States, likely a 501(c)(3) organization or similar. The actions of the Foundation will be constrained by its charter, which formalizes the specific obligations and overall mission outlined in this document. The charter will be updated on an annual basis to reflect the current goals of the Sia community.
The organization will be operated by a board of directors, initially comprising Luke Champine as President and Eddie Wang as Chairman. Luke Champine will be leaving his position at Nebulous to work at the Foundation full-time, and will seek to divest his shares of Nebulous stock along with other potential conflicts of interest. Neither Luke nor Eddie personally own any siafunds or significant quantities of siacoin.

Funding

The primary source of funding for the Foundation will come from a new block subsidy. Following a hardfork, 30 KS per block will be allocated to the "Foundation Fund," continuing in perpetuity. The existing 30 KS per block miner reward is not affected. Additionally, one year's worth of block subsidies (approximately 1.57 GS) will be allocated to the Fund immediately upon activation of the hardfork.
As detailed below, the Foundation will provably burn any coins that it cannot meaningfully spend. As such, the 30 KS subsidy should be viewed as a maximum. This allows the Foundation to grow alongside Sia without requiring additional hardforks.
The Foundation will not be funded to any degree by the possession or sale of siafunds. Siafunds were originally introduced as a means of incentivizing growth, and we still believe in their effectiveness: a siafund holder wants to increase the amount of storage on Sia as much as possible. While the Foundation obviously wants Sia to succeed, its driving force should be its charter. Deriving significant revenue from siafunds would jeopardize the Foundation's impartiality and focus. Ultimately, we want the Foundation to act in the best interests of Sia, not in growing its own budget.

Responsibilities

The Foundation inherits a great number of responsibilities from Nebulous. Each quarter, the Foundation will publish the progress it has made over the past quarter, and list the responsibilities it intends to prioritize over the coming quarter. This will be accompanied by a financial report, detailing each area of expenditure over the past quarter, and forecasting expenditures for the coming quarter. Below, we summarize some of the myriad responsibilities towards which the Foundation is expected to allocate its resources.

Maintain and enhance core Sia software

Arguably, this is the most important responsibility of the Foundation. At the heart of Sia is its consensus algorithm: regardless of other differences, all Sia software must agree upon the content and rules of the blockchain. It is therefore crucial that the algorithm be stewarded by an entity that is accountable to the community, transparent in its decision-making, and has no profit motive or other conflicts of interest.
Accordingly, Sia’s consensus functionality will no longer be directly maintained by Nebulous. Instead, the Foundation will release and maintain an implementation of a "minimal Sia full node," comprising the Sia consensus algorithm and P2P networking code. The source code will be available in a public repository, and signed binaries will be published for each release.
Other parties may use this code to provide alternative full node software. For example, Nebulous may extend the minimal full node with wallet, renter, and host functionality. The source code of any such implementation may be submitted to the Foundation for review. If the code passes review, the Foundation will provide "endorsement signatures" for the commit hash used and for binaries compiled internally by the Foundation. Specifically, these signatures assert that the Foundation believes the software contains no consensus-breaking changes or other modifications to imported Foundation code. Endorsement signatures and Foundation-compiled binaries may be displayed and distributed by the receiving party, along with an appropriate disclaimer.
A minimal full node is not terribly useful on its own; the wallet, renter, host, and other extensions are what make Sia a proper developer platform. Currently, the only implementations of these extensions are maintained by Nebulous. The Foundation will contract Nebulous to ensure that these extensions continue to receive updates and enhancements. Later on, the Foundation intends to develop its own implementations of these extensions and others. As with the minimal node software, these extensions will be open source and available in public repositories for use by any Sia node software.
With the consensus code now managed by the Foundation, the task of implementing and orchestrating hardforks becomes its responsibility as well. When the Foundation determines that a hardfork is necessary (whether through internal discussion or via community petition), a formal proposal will be drafted and submitted for public review, during which arguments for and against the proposal may be submitted to a public repository. During this time, the hardfork code will be implemented, either by Foundation employees or by external contributors working closely with the Foundation. Once the implementation is finished, final arguments will be heard. The Foundation board will then vote whether to accept or reject the proposal, and announce their decision along with appropriate justification. Assuming the proposal was accepted, the Foundation will announce the block height at which the hardfork will activate, and will subsequently release source code and signed binaries that incorporate the hardfork code.
Regardless of the Foundation's decision, it is the community that ultimately determines whether a fork is accepted or rejected – nothing can change that. Foundation node software will never automatically update, so all forks must be explicitly adopted by users. Furthermore, the Foundation will provide replay and wipeout protection for its hard forks, protecting other chains from unintended or malicious reorgs. Similarly, the Foundation will ensure that any file contracts formed prior to a fork activation will continue to be honored on both chains until they expire.
Finally, the Foundation also intends to pursue scalability solutions for the Sia blockchain. In particular, work has already begun on an implementation of Utreexo, which will greatly reduce the space requirements of fully-validating nodes (allowing a full node to be run on a smartphone) while increasing throughput and decreasing initial sync time. A hardfork implementing Utreexo will be submitted to the community as per the process detailed above.
As this is the most important responsibility of the Foundation, it will receive a significant portion of the Foundation’s budget, primarily in the form of developer salaries and contracting agreements.

Support community services

We intend to allocate 25% of the Foundation Fund towards the community. This allocation will be held and disbursed in the form of siacoins, and will pay for grants, bounties, hackathons, and other community-driven endeavours.
Any community-run service, such as a Skynet portal, explorer or web wallet, may apply to have its costs covered by the Foundation. Upon approval, the Foundation will reimburse expenses incurred by the service, subject to the exact terms agreed to. The intent of these grants is not to provide a source of income, but rather to make such services "break even" for their operators, so that members of the community can enrich the Sia ecosystem without worrying about the impact on their own finances.

Ensure easy acquisition and storage of siacoins

Most users will acquire their siacoins via an exchange. The Foundation will provide support to Sia-compatible exchanges, and pursue relevant integrations at its discretion, such as Coinbase's new Rosetta standard. The Foundation may also release DEX software that enables trading cryptocurrencies without the need for a third party. (The Foundation itself will never operate as a money transmitter.)
Increasingly, users are storing their cryptocurrency on hardware wallets. The Foundation will maintain the existing Ledger Nano S integration, and pursue further integrations at its discretion.
Of course, all hardware wallets must be paired with software running on a computer or smartphone, so the Foundation will also develop and/or maintain client-side wallet software, including both full-node wallets and "lite" wallets. Community-operated wallet services, i.e. web wallets, may be funded via grants.
Like core software maintenance, this responsibility will be funded in the form of developer salaries and contracting agreements.

Protect the ecosystem

When it comes to cryptocurrency security, patching software vulnerabilities is table stakes; there are significant legal and social threats that we must be mindful of as well. As such, the Foundation will earmark a portion of its fund to defend the community from legal action. The Foundation will also safeguard the network from 51% attacks and other threats to network security by implementing softforks and/or hardforks where necessary.
The Foundation also intends to assist in the development of a new FOSS software license, and to solicit legal memos on various Sia-related matters, such as hosting in the United States and the EU.
In a broader sense, the establishment of the Foundation makes the ecosystem more robust by transferring core development to a more neutral entity. Thanks to its funding structure, the Foundation will be immune to various forms of pressure that for-profit companies are susceptible to.

Drive adoption of Sia

Although the overriding goal of the Foundation is to make Sia the best platform it can be, all that work will be in vain if no one uses the platform. There are a number of ways the Foundation can promote Sia and get it into the hands of potential users and developers.
In-person conferences are understandably far less popular now, but the Foundation can sponsor and/or participate in virtual conferences. (In-person conferences may be held in the future, permitting circumstances.) Similarly, the Foundation will provide prizes for hackathons, which may be organized by community members, Nebulous, or the Foundation itself. Lastly, partnerships with other companies in the cryptocurrency space—or the cloud storage space—are a great way to increase awareness of Sia. To handle these responsibilities, one of the early priorities of the Foundation will be to hire a marketing director.

Fund Management

The Foundation Fund will be controlled by a multisig address. Each member of the Foundation's board will control one of the signing keys, with the signature threshold to be determined once the final composition of the board is known. (This threshold may also be increased or decreased if the number of board members changes.) Additionally, one timelocked signing key will be controlled by David Vorick. This key will act as a “dead man’s switch,” to be used in the event of an emergency that prevents Foundation board members from reaching the signature threshold. The timelock ensures that this key cannot be used unless the Foundation fails to sign a transaction for several months.
On the 1st of each month, the Foundation will use its keys to transfer all siacoins in the Fund to two new addresses. The first address will be controlled by a high-security hot wallet, and will receive approximately one month's worth of Foundation expenditures. The second address, receiving the remaining siacoins, will be a modified version of the source address: specifically, it will increase the timelock on David Vorick's signing key by one month. Any other changes to the set of signing keys, such as the arrival or departure of board members, will be incorporated into this address as well.
The Foundation Fund is allocated in SC, but many of the Foundation's expenditures must be paid in USD or other fiat currency. Accordingly, the Foundation will convert, at its discretion, a portion of its monthly withdrawals to fiat currency. We expect this conversion to be primarily facilitated by private "OTC" sales to accredited investors. The Foundation currently has no plans to speculate in cryptocurrency or other assets.
Finally, it is important that the Foundation adds value to the Sia platform well in excess of the inflation introduced by the block subsidy. For this reason, the Foundation intends to provably burn, on a quarterly basis, any coins that it cannot allocate towards any justifiable expense. In other words, coins will be burned whenever doing so provides greater value to the platform than any other use. Furthermore, the Foundation will cap its SC treasury at 5% of the total supply, and will cap its USD treasury at 4 years’ worth of predicted expenses.
 
Addendum: Hardfork Timeline
We would like to see this proposal finalized and accepted by the community no later than September 30th. A new version of siad, implementing the hardfork, will be released no later than October 15th. The hardfork will activate at block 293220, which is expected to occur around 12pm EST on January 1st, 2021.
 
Addendum: Inflation specifics
The total supply of siacoins as of January 1st, 2021 will be approximately 45.243 GS. The initial subsidy of 1.57 GS thus increases the supply by 3.47%, and the total annual inflation in 2021 will be at most 10.4% (if zero coins are burned). In 2022, total annual inflation will be at most 6.28%, and will steadily decrease in subsequent years.
 

Conclusion

We see the establishment of the Foundation as an important step in the maturation of the Sia project. It provides the ecosystem with a sustainable source of funding that can be exclusively directed towards achieving Sia's ambitious goals. Compared to other projects with far deeper pockets, Sia has always punched above its weight; once we're on equal footing, there's no telling what we'll be able to achieve.
Nevertheless, we do not propose this change lightly, and have taken pains to ensure that the Foundation will act in accordance with the ideals that this community shares. It will operate transparently, keep inflation to a minimum, and respect the user's fundamental role in decentralized systems. We hope that everyone in the community will consider this proposal carefully, and look forward to a productive discussion.
submitted by lukechampine to siacoin [link] [comments]

d down, k up, everybody's a game theorist, titcoin, build wiki on Cardano, (e-)voting, competitive marketing analysis, Goguen product update, Alexa likes Charles, David hates all, Adam in and bros in arms with the scientific counterparts of the major cryptocurrency groups, the latest AMA for all!

Decreasing d parameter
Just signed the latest change management document, I was the last in the chain so I signed it today for changing the d parameter from 0.52 to 0.5. That means we are just about to cross the threshold here in a little bit for d to fall below 0.5 which means more than half of all the blocks will be made by the community and not the OBFT nodes. That's a major milestone and at this current rate of velocity it looks like d will decrement to zero around March so lots to do, lots to talk about. Product update, two days from now, we'll go ahead and talk about that but it crossed my desk today and I was really happy and excited about that and it seemed like yesterday that d was equal to one and people were complaining that we delayed it by an epoch and now we're almost at 50 percent. For those of you who want parameter-level changes, k-level changes, they are coming and there's an enormous internal conversation about it and we've written up a powerpoint presentation and a philosophy document about why things were designed the way that they're designed.
Increasing k parameter and upcoming security video and everybody's a game theorist
My chief scientist has put an enormous amount of time into this. Aggelos is very passionate about this particular topic and what I'm going to do is similar to the security video that I did where I did an hour and a half discussion about a best practice for security. I'm going to actually do a screencasted video where I talk about this philosophy document and I'm going to read the entire document with annotations with you guys and kind of talk through it. It might end up being quite a long video. It could be several hours long but I think it's really important to talk around the design philosophy of this. It's kind of funny, everybody, when they see a cryptographic paper or math paper, they tend to just say okay you guys figure that out. No one's an expert in cryptography or math and you don't really get strong opinions about it but game theory despite the fact that the topics as complex and in some cases more complex you tend to get a lot of opinions and everybody's a game theorist. So, there was enormous amount of thought that went into the design of the system, the parameters of system, everything from the reward functions to other things and it's very important that we explain that thought process in as detailed of a way as possible. At least the philosophy behind it then I feel that the community is in a really good position to start working on the change management. It is my position that I'd love to see k largely increased. I do think that the software needs some improvements to get there especially partial delegation delegation portfolios and some enhancements into the operation of staking especially.
E-voting
I'd love to see the existence of hybrid wallets where you have a cold part a hot part and we've had a lot of conversations about that and we will present some of the progress in that matter at the product updates. If not this October certainly in November. A lot of commercialization going along, a lot of things going on and flowing around and you know, commercial teams working hard. As I mentioned we have a lot of deals in the pipeline. The Wyoming event was half political, half sales. We were really looking into e-voting and we had very productive conversations along those lines. It is my goal that Cardano e-voting software is used in political primaries and my hope is for eventually to be used in municipal and state and eventually federal elections and then in national elections for countries like Ethiopia, Mongolia and other places. Now there is a long road, long, long road to get there and many little victories that have to begin but this event. Wyoming was kind of the opener into that conversation there were seven independent parties at the independent national convention and we had a chance to talk to the leadership of many of them. We will also engage in conversation with the libertarian party leadership as well and at the very least we could talk about e-voting and also blockchain-based voting for primaries that would be great start and we'll also look into the state of Wyoming for that as well. We'll you know, tell you guys about that in time. We've already gotten a lot of inquiries about e-voting software. We tend to get them along with the (Atala) Prism inquiries. It's actually quite easy to start conversations but there are a lot of security properties that are very important like end-to-end verifiability hybrid ballots where you have both a digital and a paper ballot delegation mechanics as well as privacy mechanics that are interesting on a case-by-case basis.
Goguen, voting, future fund3, competitive marketing analysis of Ouroboros vs. EOS, Tezos, Algorand, ETH2 and Polkadot, new creative director
We'll keep chipping away at that, a lot of Goguen stuff to talk about but I'm going to reserve all of that for two days from now for the product update. We're right in the middle, Goguen metadata was the very first part of it. We already have some commercialization platform as a result of metadata, more to come and then obviously lots of smart contract stuff to come. This update and the November update are going to be very Goguen focused and also a lot of alternatives as well. We're still on schedule for an HFC event in I think November or December. I can't remember but that's going to be carrying a lot of things related multisig token locking. There's some ledger rule changes so it has to be an HFC event and that opens up a lot of the windows for Goguen foundations as well as voting on chain so fund3 will benefit very heavily from that. We're right in the guts of Daedalus right now building the voting center, the identity center, QR-code work. All this stuff, it's a lot of stuff, you know, the cell phone app was released last week. Kind of an early beta, it'll go through a lot of rapid iterations every few weeks. We'll update it, google play is a great foundation to launch things on because it's so easy to push updates to people automatically so you can rapidly iterate and be very agile in that framework and you know we've already had 3500 people involved heavily in the innovation management platform ideascale and we've got numerous bids from everything. From John Buck and the sociocracy movement to others. A lot of people want to help us improve that and we're going to see steady and systematic growth there. We're still chipping away at product marketing. Liza (Horowitz) is doing a good job, meet with her two three-times a week and right now it's Ouroboros, Ouroboros, Ouroboros... We're doing competitive analysis of Ouroboros versus EOS, Tezos, Algorand, ETH2 and Polkadot. We think that's a good set. We think we have a really good way of explaining it. David (David Likes Crypto now at IOHK) has already made some great content. We're going to release that soon alongside some other content and we'll keep chipping away at that.
We also just hired a creative director for IO Global. His name's Adam, incredibly experienced creative director, he's worked for Mercedes-Benz and dozens of other companies. He does very good work and he's been doing this for well over 20 years and so the very first set of things he's going to do is work with commercial and marketing on product marketing. In addition to building great content where hope is make that content as pretty as possible and we have Rod heavily involved in that as well to talk about distribution channels and see if we can amplify the distribution message and really get a lot of stuff done. Last thing to mention, oh yeah, iOS for catalyst. We're working on that, we submitted it to the apple store, the iOS store, but it takes a little longer to get approval for that than it does with google play but that's been submitted and it's whenever apple approves it or not. Takes a little longer for cryptocurrency stuff.
Wiki shizzle and battle for crypto, make crypto articles on wiki great again, Alexa knows Charles, Everpedia meets Charles podcast, holy-grail land of Cardano, wiki on Cardano, titcoin
Wikipedia... kind of rattled the cage a little bit. Through an intermediary we got contact with Jimmy Wales. Larry Sanger, the other co-founder also reached out to me and the everpedia guys reached out to me. Here's where we stand, we have an article, it has solidified, it's currently labeled as unreliable and you should not believe the things that are said in it which is David Gerard's work if you look at the edits. We will work with the community and try to get that article to a fair and balanced representation of Cardano and especially after the product marketing comes through. We clearly explain the product I think the Cardano article can be massively strengthened. I've told Rod to work with some specialized people to try to get that done but we are going to work very hard at a systematic approval campaign for all of the scientific articles related to blockchain technology in the cryptocurrency space. They're just terrible, if you go to the proof of work article, the proof of stake or all these things, they're just terrible. They're not well written, they're out of date and they don't reflect an adequate sampling of the science. I did talk to my chief scientist Aggelos and what we're gonna do is reach out to the scientific counterparts that most of the major cryptocurrency groups that are doing research and see if they want to work with us at an industry-wide effort to systematically improve the scientific articles in our industry so that there are a fair and balanced representation of what the current state of the art are, the criticisms, the trade-offs as well as the reference space and of course obviously we'll do quite well in that respect because we've done the science. We're the inheritor of it but it's a shame because when people search proof of stake on google usually wikipedia results are highly biased. We care about wikipedia because google cares about wikipedia, amazon cares about wikipedia.
If you ask Alexa who is Charles Hoskinson, the reason why Alexa knows is because it's reading directly from the wikipedia page. If I didn't have a wikipedia page Alexa would know that so if somebody says Alexa what is Cardano it's going to read directly from the wikipedia page and you know and we can either just pretend that reality doesn't exist or we can accept it and we as a community working with partners in the broader cryptocurrency community can universally improve the quality of cryptocurrency pages. There's been a pattern of commercial censorship on wikipedia for cryptocurrencies in general since bitcoin itself. In fact I think the bitcoin article is actually taken down once back in, might have been, 2010 or 2009 but basically wikipedia has not been a friend of cryptocurrencies. That's why everpedia exists and actually their founders reached out to me and I talked to them over twitter through PMs and we agreed to actually do a podcast. I'm going to do a streamyard, stream with these guys and they'll come on talk all about everpedia and what they do and how they are and we'll kind of go through the challenges that they've encountered. How their platform works and so forth and obviously if they want to ever leave that terrible ecosystem EOS and come to the holy-grail land of Cardano we'd be there to help them out. At least they can tell the world how amazing their product is and also the challenges they're having to overcome. We've also been in great contact with Larry Sanger.
He's going to do an internal seminar at some point with with us and talk about some protocols he's been developing since he left wikipedia specifically to decentralize knowledge management and have a truly decentralized encyclopedia. I'm really looking forward to that and I hope that presentation gives us some inspiration as an ecosystem of things we can do. That's a great piece of infrastructure regardless and after we learn a lot more about it and we talk to a lot of people in ecosystem. If we can't get people to move on over, it would be really good to see through ideascale in the innovation management platform for people to utilize the dc fund to build their own variant of wikipedia on Cardano. In the coming months there will certainly be funding available. If you guys are so passionate about this particular problem that you want to go solve it then I'd be happy to play Elon Musk with the hyperloop and write a white paper on a protocol design and really give a good first start and then you guys can go and try to commercialize that technology as Cardano native assets and Plutus smart contracts in addition to other pieces of technology that have to be brought in to make it practical.
Right now we're just, let's talk to everybody phase, and we'll talk to the everpedia guys, we're going to talk to Larry and we're going to see whoever else is in this game and of course we have to accept the incumbency as it is. So, we're working with obviously the wikipedia side to improve the quality of not only our article but all of the articles and the scientific side of things so that there's a fair and accurate representation of information. One of the reasons why I'm so concerned about this is that I am very worried that Cardano projects will get commercially censored like we were commercially censored. So, yes we do have a page but it took five years to get there and we're a multi-billion dollar project with hundreds of thousands of people. If you guys are doing cutting-edge novel interesting stuff I don't want your experience to be the same as ours where you have to wait five years for your project to get a page even after government's adopted. That's absurd, no one should be censored ever. This is very well a fight for the entire ecosystem, the entire community, not just Cardano but all cryptocurrencies: bitcoin, ethereum and Cardano have all faced commercial censorship and article deletions during their tenure so I don't want you guys to go through that. I'm hoping we can prove that situation but you know you don't put all your eggs in one basket and frankly the time has come for wikipedia to be fully decentralized and liberated from a centralized organization and massively variable quality in the editor base. If legends of valor has a page but Cardano didn't have one until recently titcoin, a pornography coin from 2015, that's deprecated, no one uses it, has a page but Cardano couldn't get one there's something seriously wrong with the quality control mechanism and we need to improve that so it'll get done.
submitted by stake_pool to cardano [link] [comments]

Technical: Taproot: Why Activate?

This is a follow-up on https://old.reddit.com/Bitcoin/comments/hqzp14/technical_the_path_to_taproot_activation/
Taproot! Everybody wants it!! But... you might ask yourself: sure, everybody else wants it, but why would I, sovereign Bitcoin HODLer, want it? Surely I can be better than everybody else because I swapped XXX fiat for Bitcoin unlike all those nocoiners?
And it is important for you to know the reasons why you, o sovereign Bitcoiner, would want Taproot activated. After all, your nodes (or the nodes your wallets use, which if you are SPV, you hopefully can pester to your wallet vendoimplementor about) need to be upgraded in order for Taproot activation to actually succeed instead of becoming a hot sticky mess.
First, let's consider some principles of Bitcoin.
I'm sure most of us here would agree that the above are very important principles of Bitcoin and that these are principles we would not be willing to remove. If anything, we would want those principles strengthened (especially the last one, financial privacy, which current Bitcoin is only sporadically strong with: you can get privacy, it just requires effort to do so).
So, how does Taproot affect those principles?

Taproot and Your /Coins

Most HODLers probably HODL their coins in singlesig addresses. Sadly, switching to Taproot would do very little for you (it gives a mild discount at spend time, at the cost of a mild increase in fee at receive time (paid by whoever sends to you, so if it's a self-send from a P2PKH or bech32 address, you pay for this); mostly a wash).
(technical details: a Taproot output is 1 version byte + 32 byte public key, while a P2WPKH (bech32 singlesig) output is 1 version byte + 20 byte public key hash, so the Taproot output spends 12 bytes more; spending from a P2WPKH requires revealing a 32-byte public key later, which is not needed with Taproot, and Taproot signatures are about 9 bytes smaller than P2WPKH signatures, but the 32 bytes plus 9 bytes is divided by 4 because of the witness discount, so it saves about 11 bytes; mostly a wash, it increases blockweight by about 1 virtual byte, 4 weight for each Taproot-output-input, compared to P2WPKH-output-input).
However, as your HODLings grow in value, you might start wondering if multisignature k-of-n setups might be better for the security of your savings. And it is in multisignature that Taproot starts to give benefits!
Taproot switches to using Schnorr signing scheme. Schnorr makes key aggregation -- constructing a single public key from multiple public keys -- almost as trivial as adding numbers together. "Almost" because it involves some fairly advanced math instead of simple boring number adding, but hey when was the last time you added up your grocery list prices by hand huh?
With current P2SH and P2WSH multisignature schemes, if you have a 2-of-3 setup, then to spend, you need to provide two different signatures from two different public keys. With Taproot, you can create, using special moon math, a single public key that represents your 2-of-3 setup. Then you just put two of your devices together, have them communicate to each other (this can be done airgapped, in theory, by sending QR codes: the software to do this is not even being built yet, but that's because Taproot hasn't activated yet!), and they will make a single signature to authorize any spend from your 2-of-3 address. That's 73 witness bytes -- 18.25 virtual bytes -- of signatures you save!
And if you decide that your current setup with 1-of-1 P2PKH / P2WPKH addresses is just fine as-is: well, that's the whole point of a softfork: backwards-compatibility; you can receive from Taproot users just fine, and once your wallet is updated for Taproot-sending support, you can send to Taproot users just fine as well!
(P2WPKH and P2WSH -- SegWit v0 -- addresses start with bc1q; Taproot -- SegWit v1 --- addresses start with bc1p, in case you wanted to know the difference; in bech32 q is 0, p is 1)
Now how about HODLers who keep all, or some, of their coins on custodial services? Well, any custodial service worth its salt would be doing at least 2-of-3, or probably something even bigger, like 11-of-15. So your custodial service, if it switched to using Taproot internally, could save a lot more (imagine an 11-of-15 getting reduced from 11 signatures to just 1!), which --- we can only hope! --- should translate to lower fees and better customer service from your custodial service!
So I think we can say, very accurately, that the Bitcoin principle --- that YOU are in control of your money --- can only be helped by Taproot (if you are doing multisignature), and, because P2PKH and P2WPKH remain validly-usable addresses in a Taproot future, will not be harmed by Taproot. Its benefit to this principle might be small (it mostly only benefits multisignature users) but since it has no drawbacks with this (i.e. singlesig users can continue to use P2WPKH and P2PKH still) this is still a nice, tidy win!
(even singlesig users get a minor benefit, in that multisig users will now reduce their blockchain space footprint, so that fees can be kept low for everybody; so for example even if you have your single set of private keys engraved on titanium plates sealed in an airtight box stored in a safe buried in a desert protected by angry nomads riding giant sandworms because you're the frickin' Kwisatz Haderach, you still gain some benefit from Taproot)
And here's the important part: if P2PKH/P2WPKH is working perfectly fine with you and you decide to never use Taproot yourself, Taproot will not affect you detrimentally. First do no harm!

Taproot and Your Contracts

No one is an island, no one lives alone. Give and you shall receive. You know: by trading with other people, you can gain expertise in some obscure little necessity of the world (and greatly increase your productivity in that little field), and then trade the products of your expertise for necessities other people have created, all of you thereby gaining gains from trade.
So, contracts, which are basically enforceable agreements that facilitate trading with people who you do not personally know and therefore might not trust.
Let's start with a simple example. You want to buy some gewgaws from somebody. But you don't know them personally. The seller wants the money, you want their gewgaws, but because of the lack of trust (you don't know them!! what if they're scammers??) neither of you can benefit from gains from trade.
However, suppose both of you know of some entity that both of you trust. That entity can act as a trusted escrow. The entity provides you security: this enables the trade, allowing both of you to get gains from trade.
In Bitcoin-land, this can be implemented as a 2-of-3 multisignature. The three signatories in the multisgnature would be you, the gewgaw seller, and the escrow. You put the payment for the gewgaws into this 2-of-3 multisignature address.
Now, suppose it turns out neither of you are scammers (whaaaat!). You receive the gewgaws just fine and you're willing to pay up for them. Then you and the gewgaw seller just sign a transaction --- you and the gewgaw seller are 2, sufficient to trigger the 2-of-3 --- that spends from the 2-of-3 address to a singlesig the gewgaw seller wants (or whatever address the gewgaw seller wants).
But suppose some problem arises. The seller gave you gawgews instead of gewgaws. Or you decided to keep the gewgaws but not sign the transaction to release the funds to the seller. In either case, the escrow is notified, and if it can sign with you to refund the funds back to you (if the seller was a scammer) or it can sign with the seller to forward the funds to the seller (if you were a scammer).
Taproot helps with this: like mentioned above, it allows multisignature setups to produce only one signature, reducing blockchain space usage, and thus making contracts --- which require multiple people, by definition, you don't make contracts with yourself --- is made cheaper (which we hope enables more of these setups to happen for more gains from trade for everyone, also, moon and lambos).
(technology-wise, it's easier to make an n-of-n than a k-of-n, making a k-of-n would require a complex setup involving a long ritual with many communication rounds between the n participants, but an n-of-n can be done trivially with some moon math. You can, however, make what is effectively a 2-of-3 by using a three-branch SCRIPT: either 2-of-2 of you and seller, OR 2-of-2 of you and escrow, OR 2-of-2 of escrow and seller. Fortunately, Taproot adds a facility to embed a SCRIPT inside a public key, so you can have a 2-of-2 Taprooted address (between you and seller) with a SCRIPT branch that can instead be spent with 2-of-2 (you + escrow) OR 2-of-2 (seller + escrow), which implements the three-branched SCRIPT above. If neither of you are scammers (hopefully the common case) then you both sign using your keys and never have to contact the escrow, since you are just using the escrow public key without coordinating with them (because n-of-n is trivial but k-of-n requires setup with communication rounds), so in the "best case" where both of you are honest traders, you also get a privacy boost, in that the escrow never learns you have been trading on gewgaws, I mean ewww, gawgews are much better than gewgaws and therefore I now judge you for being a gewgaw enthusiast, you filthy gewgawer).

Taproot and Your Contracts, Part 2: Cryptographic Boogaloo

Now suppose you want to buy some data instead of things. For example, maybe you have some closed-source software in trial mode installed, and want to pay the developer for the full version. You want to pay for an activation code.
This can be done, today, by using an HTLC. The developer tells you the hash of the activation code. You pay to an HTLC, paying out to the developer if it reveals the preimage (the activation code), or refunding the money back to you after a pre-agreed timeout. If the developer claims the funds, it has to reveal the preimage, which is the activation code, and you can now activate your software. If the developer does not claim the funds by the timeout, you get refunded.
And you can do that, with HTLCs, today.
Of course, HTLCs do have problems:
Fortunately, with Schnorr (which is enabled by Taproot), we can now use the Scriptless Script constuction by Andrew Poelstra. This Scriptless Script allows a new construction, the PTLC or Pointlocked Timelocked Contract. Instead of hashes and preimages, just replace "hash" with "point" and "preimage" with "scalar".
Or as you might know them: "point" is really "public key" and "scalar" is really a "private key". What a PTLC does is that, given a particular public key, the pointlocked branch can be spent only if the spender reveals the private key of the given public key to you.
Another nice thing with PTLCs is that they are deniable. What appears onchain is just a single 2-of-2 signature between you and the developemanufacturer. It's like a magic trick. This signature has no special watermarks, it's a perfectly normal signature (the pledge). However, from this signature, plus some datta given to you by the developemanufacturer (known as the adaptor signature) you can derive the private key of a particular public key you both agree on (the turn). Anyone scraping the blockchain will just see signatures that look just like every other signature, and as long as nobody manages to hack you and get a copy of the adaptor signature or the private key, they cannot get the private key behind the public key (point) that the pointlocked branch needs (the prestige).
(Just to be clear, the public key you are getting the private key from, is distinct from the public key that the developemanufacturer will use for its funds. The activation key is different from the developer's onchain Bitcoin key, and it is the activation key whose private key you will be learning, not the developer's/manufacturer's onchain Bitcoin key).
So:
Taproot lets PTLCs exist onchain because they enable Schnorr, which is a requirement of PTLCs / Scriptless Script.
(technology-wise, take note that Scriptless Script works only for the "pointlocked" branch of the contract; you need normal Script, or a pre-signed nLockTimed transaction, for the "timelocked" branch. Since Taproot can embed a script, you can have the Taproot pubkey be a 2-of-2 to implement the Scriptless Script "pointlocked" branch, then have a hidden script that lets you recover the funds with an OP_CHECKLOCKTIMEVERIFY after the timeout if the seller does not claim the funds.)

Quantum Quibbles!

Now if you were really paying attention, you might have noticed this parenthetical:
(technical details: a Taproot output is 1 version byte + 32 byte public key, while a P2WPKH (bech32 singlesig) output is 1 version byte + 20 byte public key hash...)
So wait, Taproot uses raw 32-byte public keys, and not public key hashes? Isn't that more quantum-vulnerable??
Well, in theory yes. In practice, they probably are not.
It's not that hashes can be broken by quantum computes --- they're still not. Instead, you have to look at how you spend from a P2WPKH/P2PKH pay-to-public-key-hash.
When you spend from a P2PKH / P2WPKH, you have to reveal the public key. Then Bitcoin hashes it and checks if this matches with the public-key-hash, and only then actually validates the signature for that public key.
So an unconfirmed transaction, floating in the mempools of nodes globally, will show, in plain sight for everyone to see, your public key.
(public keys should be public, that's why they're called public keys, LOL)
And if quantum computers are fast enough to be of concern, then they are probably fast enough that, in the several minutes to several hours from broadcast to confirmation, they have already cracked the public key that is openly broadcast with your transaction. The owner of the quantum computer can now replace your unconfirmed transaction with one that pays the funds to itself. Even if you did not opt-in RBF, miners are still incentivized to support RBF on RBF-disabled transactions.
So the extra hash is not as significant a protection against quantum computers as you might think. Instead, the extra hash-and-compare needed is just extra validation effort.
Further, if you have ever, in the past, spent from the address, then there exists already a transaction indelibly stored on the blockchain, openly displaying the public key from which quantum computers can derive the private key. So those are still vulnerable to quantum computers.
For the most part, the cryptographers behind Taproot (and Bitcoin Core) are of the opinion that quantum computers capable of cracking Bitcoin pubkeys are unlikely to appear within a decade or two.
So:
For now, the homomorphic and linear properties of elliptic curve cryptography provide a lot of benefits --- particularly the linearity property is what enables Scriptless Script and simple multisignature (i.e. multisignatures that are just 1 signature onchain). So it might be a good idea to take advantage of them now while we are still fairly safe against quantum computers. It seems likely that quantum-safe signature schemes are nonlinear (thus losing these advantages).

Summary

I Wanna Be The Taprooter!

So, do you want to help activate Taproot? Here's what you, mister sovereign Bitcoin HODLer, can do!

But I Hate Taproot!!

That's fine!

Discussions About Taproot Activation

submitted by almkglor to Bitcoin [link] [comments]

Taproot, CoinJoins, and Cross-Input Signature Aggregation

It is a very common misconception that the upcoming Taproot upgrade helps CoinJoin.
TLDR: The upcoming Taproot upgrade does not help equal-valued CoinJoin at all, though it potentially increases the privacy of other protocols, such as the Lightning Network, and escrow contract schemes.
If you want to learn more, read on!

Equal-valued CoinJoins

Let's start with equal-valued CoinJoins, the type JoinMarket and Wasabi use. What happens is that some number of participants agree on some common value all of them use. With JoinMarket the taker defines this value and pays the makers to agree to it, with Wasabi the server defines a value approximately 0.1 BTC.
Then, each participant provides inputs that they unilaterally control, totaling equal or greater than the common value. Typically since each input is unilaterally controlled, each input just requires a singlesig. Each participant also provides up to two addresses they control: one of these will be paid with the common value, while the other will be used for any extra value in the inputs they provided (i.e. the change output).
The participants then make a single transaction that spends all the provided inputs and pays out to the appropriate outputs. The inputs and outputs are shuffled in some secure manner. Then the unsigned transaction is distributed back to all participants.
Finally, each participant checks that the transaction spends the inputs it provided (and more importantly does not spend any other coins it might own that it did not provide for this CoinJoin!) and that the transaction pays out to the appropriate address(es) it controls. Once they have validated the transaction, they ratify it by signing for each of the inputs it provided.
Once every participant has provided signatures for all inputs it registered, the transaction is now completely signed and the CoinJoin transaction is now validly confirmable.
CoinJoin is a very simple and direct privacy boost, it requires no SCRIPTs, needs only singlesig, etc.

Privacy

Let's say we have two participants who have agreed on a common amount of 0.1 BTC. One provides a 0.105 coin as input, the other provides a 0.114 coin as input. This results in a CoinJoin with a 0.105 coin and a 0.114 coin as input, and outputs with 0.1, 0.005, 0.014, and 0.1 BTC.
Now obviously the 0.005 output came from the 0.105 input, and the 0.014 output came from the 0.114 input.
But the two 0.1 BTC outputs cannot be correlated with either input! There is no correlating information, since either output could have come from either input. That is how common CoinJoin implementations like Wasabi and JoinMarket gain privacy.

Banning CoinJoins

Unfortunately, large-scale CoinJoins like that made by Wasabi and JoinMarket are very obvious.
All you have to do is look for a transactions where, say, more than 3 outputs are the same equal value, and the number of inputs is equal or larger than the number of equal-valued outputs. Thus, it is trivial to identify equal-valued CoinJoins made by Wasabi and JoinMarket. You can even trivially differentiate them: Wasabi equal-valued CoinJoins are going to have a hundred or more inputs, with outputs that are in units of approximately 0.1 BTC, while JoinMarket CoinJoins have equal-valued outputs of less than a dozen (between 4 to 6 usually) and with the common value varying wildly from as low as 0.001 BTC to as high as a dozen BTC or more.
This has led to a number of anti-privacy exchanges to refuse to credit custodially-held accounts if the incoming deposit is within a few hops of an equal-valued CoinJoin, usually citing concerns about regulations. Crucially, the exchange continues to hold private keys for those "banned" deposits, and can still spend them, thus this is effectively a theft. If your exchange does this to you, you should report that exchange as stealing money from its customers. Not your keys not your coins.
Thus, CoinJoins represent a privacy tradeoff:

Taproot

Let's now briefly discuss that nice new shiny thing called Taproot.
Taproot includes two components:
This has some nice properties:

Taproot DOES NOT HELP CoinJoin

So let's review!
CoinJoin:
Taproot:
There is absolutely no overlap. Taproot helps things that CoinJoin does not use. CoinJoin uses things that Taproot does not improve.

B-but They Said!!

A lot of early reporting on Taproot claimed that Taproot benefits CoinJoin.
What they are confusing is that earlier drafts of Taproot included a feature called cross-input signature aggregation.
In current Bitcoin, every input, to be spent, has to be signed individually. With cross-input signature aggregation, all inputs that support this feature are signed with a single signature that covers all those inputs. So for example if you would spend two inputs, current Bitcoin requires a signature for each input, but with cross-input signature aggregation you can sign both of them with a single signature. This works even if the inputs have different public keys: two inputs with cross-input signature aggregation effectively define a 2-of-2 public key, and you can only sign for that input if you know the private keys for both inputs, or if you are cooperatively signing with somebody who knows the private key of the other input.
This helps CoinJoin costs. Since CoinJoins will have lots of inputs (each participant will provide at least one, and probably will provide more, and larger participant sets are better for more privacy in CoinJoin), if all of them enabled cross-input signature aggregation, such large CoinJoins can have only a single signature.
This complicates the signing process for CoinJoins (the signers now have to sign cooperatively) but it can be well worth it for the reduced signature size and onchain cost.
But note that the while cross-input signature aggregation improves the cost of CoinJoins, it does not improve the privacy! Equal-valued CoinJoins are still obvious and still readily bannable by privacy-hating exchanges. It does not improve the privacy of CoinJoin. Instead, see https://old.reddit.com/Bitcoin/comments/gqb3udesign_for_a_coinswap_implementation_fo

Why isn't cross-input signature aggregation in?

There's some fairly complex technical reasons why cross-input signature aggregation isn't in right now in the current Taproot proposal.
The primary reason was to reduce the technical complexity of Taproot, in the hope that it would be easier to convince users to activate (while support for Taproot is quite high, developers have become wary of being hopeful that new proposals will ever activate, given the previous difficulties with SegWit).
The main technical complexity here is that it interacts with future ways to extend Bitcoin.
The rest of this writeup assumes you already know about how Bitcoin SCRIPT works. If you don't understand how Bitcoin SCRIPT works at the low-level, then the TLDR is that cross-input signature aggregation complicates how to extend Bitcoin in the future, so it was deferred to let the develoeprs think more about it.
(this is how I understand it; perhaps pwuille or ajtowns can give a better summary.)
In detail, Taproot also introduces OP_SUCCESS opcodes. If you know about the OP_NOP opcodes already defined in current Bitcoin, well, OP_SUCCESS is basically "OP_NOP done right".
Now, OP_NOP is a do-nothing operation. It can be replaced in future versions of Bitcoin by having that operation check some condition, and then fail if the condition is not satisfied. For example, both OP_CHECKLOCKTIMEVERIFY and OP_CHECKSEQUENCEVERIFY were previously OP_NOP opcodes. Older nodes will see an OP_CHECKLOCKTIMEVERIFY and think it does nothing, but newer nodes will check if the nLockTime field has a correct specified value, and fail if the condition is not satisfied. Since most of the nodes on the network are using much newer versions of the node software, older nodes are protected from miners who try to misspend any OP_CHECKLOCKTIMEVERIFY/OP_CHECKSEQUENCEVERIFY, and those older nodes will still remain capable of synching with the rest of the network: a dedication to strict backward-compatibility necessary for a consensus system.
Softforks basically mean that a script that passes in the latest version must also be passing in all older versions. A script cannot be passing in newer versions but failing in older versions, because that would kick older nodes off the network (i.e. it would be a hardfork).
But OP_NOP is a very restricted way of adding opcodes. Opcodes that replace OP_NOP can only do one thing: check if some condition is true. They can't push new data on the stack, they can't pop items off the stack. For example, suppose instead of OP_CHECKLOCKTIMEVERIFY, we had added a OP_GETBLOCKHEIGHT opcode. This opcode would push the height of the blockchain on the stack. If this command replaced an older OP_NOP opcode, then a script like OP_GETBLOCKHEIGHT 650000 OP_EQUAL might pass in some future Bitcoin version, but older versions would see OP_NOP 650000 OP_EQUAL, which would fail because OP_EQUAL expects two items on the stack. So older versions will fail a SCRIPT that newer versions will pass, which is a hardfork and thus a backwards incompatibility.
OP_SUCCESS is different. Instead, old nodes, when parsing the SCRIPT, will see OP_SUCCESS, and, without executing the body, will consider the SCRIPT as passing. So, the OP_GETBLOCKHEIGHT 650000 OP_EQUAL example will now work: a future version of Bitcoin might pass it, and existing nodes that don't understand OP_GETBLOCKHEIGHT will se OP_SUCCESS 650000 OP_EQUAL, and will not execute the SCRIPT at all, instead passing it immediately. So a SCRIPT that might pass in newer versions will pass for older versions, which keeps the back-compatibility consensus that a softfork needs.
So how does OP_SUCCESS make things difficult for cross-input signatur aggregation? Well, one of the ways to ask for a signature to be verified is via the opcodes OP_CHECKSIGVERIFY. With cross-input signature aggregation, if a public key indicates it can be used for cross-input signature aggregation, instead of OP_CHECKSIGVERIFY actually requiring the signature on the stack, the stack will contain a dummy 0 value for the signature, and the public key is instead added to a "sum" public key (i.e. an n-of-n that is dynamically extended by one more pubkey for each OP_CHECKSIGVERIFY operation that executes) for the single signature that is verified later by the cross-input signature aggregation validation algorithm00.
The important part here is that the OP_CHECKSIGVERIFY has to execute, in order to add its public key to the set of public keys to be checked in the single signature.
But remember that an OP_SUCCESS prevents execution! As soon as the SCRIPT is parsed, if any opcode is OP_SUCCESS, that is considered as passing, without actually executing the SCRIPT, because the OP_SUCCESS could mean something completely different in newer versions and current versions should assume nothing about what it means. If the SCRIPT contains some OP_CHECKSIGVERIFY command in addition to an OP_SUCCESS, that command is not executed by current versions, and thus they cannot add any public keys given by OP_CHECKSIGVERIFY. Future versions also have to accept that: if they parsed an OP_SUCCESS command that has a new meaning in the future, and then execute an OP_CHECKSIGVERIFY in that SCRIPT, they cannot add the public key into the same "sum" public key that older nodes use, because older nodes cannot see them. This means that you might need more than one signature in the future, in the presence of an opcode that replaces some OP_SUCCESS.
Thus, because of the complexity of making cross-input signature aggregation work compatibly with future extensions to the protocol, cross-input signature aggregation was deferred.
submitted by almkglor to Bitcoin [link] [comments]

The power of "import electrum" as a python bitcoin scripting engine

I've been a big fan of Electrum as a wallet for a while now. Traditionally, when I wanted to do bitcoin scripting I would use either trezorlib, pycoin, or bitcoinlib. But recently I was digging a bit deeper into the Electrum source and found it to be one of the simpler python libraries to use to craft bitcoin transactions.
One of the nicer things about Electrum as a scripting engine is that you can drop the standalone app or AppImage on a system and run your scripts directly through the console. This makes doing things on Tails or other locked down systems much easier. To run one one of your scripts (without the event loop) simply type (assuming you correct the file path):
with open(r"myscript.py", 'r') as s: exec(s.read())
Obviously only do this with scripts you've personally authored. Never run random code on your machine especially when wallet private keys are in play.
There are already some great scripting examples in the electrum\scripts folder, but most of these use the event loop which brings in a lot of overhead. I found simple TXN processing can easily be done without spawning an full electrum thread. I'd be happy to PR the samples if there is any interest in this style from the maintainers.
Here's two examples I put together that craft a BIP65 spending transaction. It turned out to be much simpler than I imagined. I did it both in bitcoinlib and electrum. The structure is very similar and should hopefully be easier to follow. Feel free to start a PythonRoastMe on it.
Two things of note. I had to disable R-value grinding (nuked while loop) so that I had parity with bitcoinlib, which hasn't rolled it out yet. This is why the TXIDs differ. I also had to override the the PartialTransaction.get_preimage_script method since it makes certain multisig assumptions that don't apply to generic scripting.
Reference: * Electrum script to spend an OP_HODL P2WSH address (txid 3a461e6...78de2b6) * Electrum script to spend an OP_HODL P2SH address (txid a8110bb...3dadc93) * BitcoinLib script to spend an OP_HODL P2WSH address (txid 3a461e6...78de2b6) * BitcoinLib script to spend an OP_HODL P2SH address (txid a8110bb...3dadc93) * TXID 3a461e6...78de2b6 (P2WSH) on the blockchain * TXID a8110bb...3dadc93 (P2SH) on the blockchain * BIP-0065: OP_CHECKLOCKTIMEVERIFY (aka OP_HODL) * BIP-0141: P2WSH symantics * BIP-0016: P2SH symantics
submitted by brianddk to Electrum [link] [comments]

Zano Newcomers Introduction/FAQ - please read!

Welcome to the Zano Sticky Introduction/FAQ!

https://preview.redd.it/al1gy9t9v9q51.png?width=424&format=png&auto=webp&s=b29a60402d30576a4fd95f592b392fae202026ca
Hopefully any questions you have will be answered by the resources below, but if you have additional questions feel free to ask them in the comments. If you're quite technically-minded, the Zano whitepaper gives a thorough overview of Zano's design and its main features.
So, what is Zano? In brief, Zano is a project started by the original developers of CryptoNote. Coins with market caps totalling well over a billion dollars (Monero, Haven, Loki and countless others) run upon the codebase they created. Zano is a continuation of their efforts to create the "perfect money", and brings a wealth of enhancements to their original CryptoNote code.
Development happens at a lightning pace, as the Github activity shows, but Zano is still very much a work-in-progress. Let's cut right to it:
Here's why you should pay attention to Zano over the next 12-18 months. Quoting from a recent update:
Anton Sokolov has recently joined the Zano team. ... For the last months Anton has been working on theoretical work dedicated to log-size ring signatures. These signatures theoretically allows for a logarithmic relationship between the number of decoys and the size/performance of transactions. This means that we can set mixins at a level from up to 1000, keeping the reasonable size and processing speed of transactions. This will take Zano’s privacy to a whole new level, and we believe this technology will turn out to be groundbreaking!
If successful, this scheme will make Zano the most private, powerful and performant CryptoNote implementation on the planet. Bar none. A quantum leap in privacy with a minimal increase in resource usage. And if there's one team capable of pulling it off, it's this one.

What else makes Zano special?

You mean aside from having "the Godfather of CryptoNote" as the project lead? ;) Actually, the calibre of the developers/researchers at Zano probably is the project's single greatest strength. Drawing on years of experience, they've made careful design choices, optimizing performance with an asynchronous core architecture, and flexibility and extensibility with a modular code structure. This means that the developers are able to build and iterate fast, refining features and adding new ones at a rate that makes bigger and better-funded teams look sluggish at best.
Zano also has some unique features that set it apart from similar projects:
Privacy Firstly, if you're familiar with CryptoNote you won't be surprised that Zano transactions are private. The perfect money is fungible, and therefore must be untraceable. Bitcoin, for the most part, does little to hide your transaction data from unscrupulous observers. With Zano, privacy is the default.
The untraceability and unlinkability of Zano transactions come from its use of ring signatures and stealth addresses. What this means is that no outside observer is able to tell if two transactions were sent to the same address, and for each transaction there is a set of possible senders that make it impossible to determine who the real sender is.
Hybrid PoW-PoS consensus mechanism Zano achieves an optimal level of security by utilizing both Proof of Work and Proof of Stake for consensus. By combining the two systems, it mitigates their individual vulnerabilities (see 51% attack and "nothing at stake" problem). For an attack on Zano to have even a remote chance of success the attacker would have to obtain not only a majority of hashing power, but also a majority of the coins involved in staking. The system and its design considerations are discussed at length in the whitepaper.
Aliases Here's a stealth address: ZxDdULdxC7NRFYhCGdxkcTZoEGQoqvbZqcDHj5a7Gad8Y8wZKAGZZmVCUf9AvSPNMK68L8r8JfAfxP4z1GcFQVCS2Jb9wVzoe. I have a hard enough time remembering my phone number. Fortunately, Zano has an alias system that lets you register an address to a human-readable name. (@orsonj if you want to anonymously buy me a coffee)
Multisig
Multisignature (multisig) refers to requiring multiple keys to authorize a Zano transaction. It has a number of applications, such as dividing up responsibility for a single Zano wallet among multiple parties, or creating backups where loss of a single seed doesn't lead to loss of the wallet.
Multisig and escrow are key components of the planned Decentralized Marketplace (see below), so consideration was given to each of them from the design stages. Thus Zano's multisig, rather than being tagged on at the wallet-level as an afterthought, is part of its its core architecture being incorporated at the protocol level. This base-layer integration means months won't be spent in the future on complicated refactoring efforts in order to integrate multisig into a codebase that wasn't designed for it. Plus, it makes it far easier for third-party developers to include multisig (implemented correctly) in any Zano wallets and applications they create in the future.
(Double Deposit MAD) Escrow
With Zano's escrow service you can create fully customizable p2p contracts that are designed to, once signed by participants, enforce adherence to their conditions in such a way that no trusted third-party escrow agent is required.
https://preview.redd.it/jp4oghyhv9q51.png?width=1762&format=png&auto=webp&s=12a1e76f76f902ed328886283050e416db3838a5
The Particl project, aside from a couple of minor differences, uses an escrow scheme that works the same way, so I've borrowed the term they coined ("Double Deposit MAD Escrow") as I think it describes the scheme perfectly. The system requires participants to make additional deposits, which they will forfeit if there is any attempt to act in a way that breaches the terms of the contract. Full details can be found in the Escrow section of the whitepaper.
The usefulness of multisig and the escrow system may not seem obvious at first, but as mentioned before they'll form the backbone of Zano's Decentralized Marketplace service (described in the next section).

What does the future hold for Zano?

The planned upgrade to Zano's privacy, mentioned at the start, is obviously one of the most exciting things the team is working on, but it's not the only thing.
Zano Roadmap
Decentralized Marketplace
From the beginning, the Zano team's goal has been to create the perfect money. And money can't just be some vehicle for speculative investment, money must be used. To that end, the team have created a set of tools to make it as simple as possible for Zano to be integrated into eCommerce platforms. Zano's API’s and plugins are easy to use, allowing even those with very little coding experience to use them in their E-commerce-related ventures. The culmination of this effort will be a full Decentralized Anonymous Marketplace built on top of the Zano blockchain. Rather than being accessed via the wallet, it will act more as a service - Marketplace as a Service (MAAS) - for anyone who wishes to use it. The inclusion of a simple "snippet" of code into a website is all that's needed to become part a global decentralized, trustless and private E-commerce network.
Atomic Swaps
Just as Zano's marketplace will allow you to transact without needing to trust your counterparty, atomic swaps will let you to easily convert between Zano and other cyryptocurrencies without having to trust a third-party service such as a centralized exchange. On top of that, it will also lead to the way to Zano's inclusion in the many decentralized exchange (DEX) services that have emerged in recent years.

Where can I buy Zano?

Zano's currently listed on the following exchanges:
https://coinmarketcap.com/currencies/zano/markets/
It goes without saying, neither I nor the Zano team work for any of the exchanges or can vouch for their reliability. Use at your own risk and never leave coins on a centralized exchange for longer than necessary. Your keys, your coins!
If you have any old graphics cards lying around(both AMD & NVIDIA), then Zano is also mineable through its unique ProgPowZ algorithm. Here's a guide on how to get started.
Once you have some Zano, you can safely store it in one of the desktop or mobile wallets (available for all major platforms).

How can I support Zano?

Zano has no marketing department, which is why this post has been written by some guy and not the "Chief Growth Engineer @ Zano Enterprises". The hard part is already done: there's a team of world class developers and researchers gathered here. But, at least at the current prices, the team's funds are enough to cover the cost of development and little more. So the job of publicizing the project falls to the community. If you have any experience in community building/growth hacking at another cryptocurrency or open source project, or if you're a Zano holder who would like to ensure the project's long-term success by helping to spread the word, then send me a pm. We need to get organized.
Researchers and developers are also very welcome. Working at the cutting edge of mathematics and cryptography means Zano provides challenging and rewarding work for anyone in those fields. Please contact the project's Community Manager u/Jed_T if you're interested in joining the team.
Social Links:
Twitter
Discord Server
Telegram Group
Medium blog
I'll do my best to keep this post accurate and up to date. Message me please with any suggested improvements and leave any questions you have below.
Welcome to the Zano community and the new decentralized private economy!
submitted by OrsonJ to Zano [link] [comments]

What is your Bitcoin Maturity Score?

How many of the 25 steps in the bitcoin rabbit hole have you mastered? Be honest. Count how many and divide your score by 2.5.
Your Score: <5: learner / weak hands 5-7: hodler 8-9: mature 10: orange pilled
Post your result below.
The Bitcoin Journey: 1. That (log) price chart! 🧐 2. Digital scarce? 🤔 3. Satochi 4. Blockchain 5. Alts 6. Mining, halvings, diff adjustment 7. How do I get it? 8. Wallets, keys, seeds, exchanges 9. Crypto Twitter 10. Fees, hashrate, mempool, txs 11. Money, inflation, central banks 12. Stocks, S&P500, 13. Charts, TA, RSI, MA’s, triangles, patterns 🤓 14. Keynes, Austrian economics 15. Bull/bear market, trading, win/lose 16. Network effects & adoption 17. Gold, Silver, real estate 18. Full node, electrum pvt server 19. Evangelize / orange pilled 💊 20. All-in / auto-dca 21. Immaculate conception 22. NGU, game theory 23. Cosmic renaissance 24. Opsec, multisig 25. Maximalism
Let me know your score & what’s missing from your journey. Also accepting suggestions for better results categories/ descriptions.
submitted by mbrookson to Bitcoin [link] [comments]

[ Bitcoin ] Technical: Taproot: Why Activate?

Topic originally posted in Bitcoin by almkglor [link]
This is a follow-up on https://old.reddit.com/Bitcoin/comments/hqzp14/technical_the_path_to_taproot_activation/
Taproot! Everybody wants it!! But... you might ask yourself: sure, everybody else wants it, but why would I, sovereign Bitcoin HODLer, want it? Surely I can be better than everybody else because I swapped XXX fiat for Bitcoin unlike all those nocoiners?
And it is important for you to know the reasons why you, o sovereign Bitcoiner, would want Taproot activated. After all, your nodes (or the nodes your wallets use, which if you are SPV, you hopefully can pester to your wallet vendoimplementor about) need to be upgraded in order for Taproot activation to actually succeed instead of becoming a hot sticky mess.
First, let's consider some principles of Bitcoin.
I'm sure most of us here would agree that the above are very important principles of Bitcoin and that these are principles we would not be willing to remove. If anything, we would want those principles strengthened (especially the last one, financial privacy, which current Bitcoin is only sporadically strong with: you can get privacy, it just requires effort to do so).
So, how does Taproot affect those principles?

Taproot and Your /Coins

Most HODLers probably HODL their coins in singlesig addresses. Sadly, switching to Taproot would do very little for you (it gives a mild discount at spend time, at the cost of a mild increase in fee at receive time (paid by whoever sends to you, so if it's a self-send from a P2PKH or bech32 address, you pay for this); mostly a wash).
(technical details: a Taproot output is 1 version byte + 32 byte public key, while a P2WPKH (bech32 singlesig) output is 1 version byte + 20 byte public key hash, so the Taproot output spends 12 bytes more; spending from a P2WPKH requires revealing a 32-byte public key later, which is not needed with Taproot, and Taproot signatures are about 9 bytes smaller than P2WPKH signatures, but the 32 bytes plus 9 bytes is divided by 4 because of the witness discount, so it saves about 11 bytes; mostly a wash, it increases blockweight by about 1 virtual byte, 4 weight for each Taproot-output-input, compared to P2WPKH-output-input).
However, as your HODLings grow in value, you might start wondering if multisignature k-of-n setups might be better for the security of your savings. And it is in multisignature that Taproot starts to give benefits!
Taproot switches to using Schnorr signing scheme. Schnorr makes key aggregation -- constructing a single public key from multiple public keys -- almost as trivial as adding numbers together. "Almost" because it involves some fairly advanced math instead of simple boring number adding, but hey when was the last time you added up your grocery list prices by hand huh?
With current P2SH and P2WSH multisignature schemes, if you have a 2-of-3 setup, then to spend, you need to provide two different signatures from two different public keys. With Taproot, you can create, using special moon math, a single public key that represents your 2-of-3 setup. Then you just put two of your devices together, have them communicate to each other (this can be done airgapped, in theory, by sending QR codes: the software to do this is not even being built yet, but that's because Taproot hasn't activated yet!), and they will make a single signature to authorize any spend from your 2-of-3 address. That's 73 witness bytes -- 18.25 virtual bytes -- of signatures you save!
And if you decide that your current setup with 1-of-1 P2PKH / P2WPKH addresses is just fine as-is: well, that's the whole point of a softfork: backwards-compatibility; you can receive from Taproot users just fine, and once your wallet is updated for Taproot-sending support, you can send to Taproot users just fine as well!
(P2WPKH and P2WSH -- SegWit v0 -- addresses start with bc1q; Taproot -- SegWit v1 --- addresses start with bc1p, in case you wanted to know the difference; in bech32 q is 0, p is 1)
Now how about HODLers who keep all, or some, of their coins on custodial services? Well, any custodial service worth its salt would be doing at least 2-of-3, or probably something even bigger, like 11-of-15. So your custodial service, if it switched to using Taproot internally, could save a lot more (imagine an 11-of-15 getting reduced from 11 signatures to just 1!), which --- we can only hope! --- should translate to lower fees and better customer service from your custodial service!
So I think we can say, very accurately, that the Bitcoin principle --- that YOU are in control of your money --- can only be helped by Taproot (if you are doing multisignature), and, because P2PKH and P2WPKH remain validly-usable addresses in a Taproot future, will not be harmed by Taproot. Its benefit to this principle might be small (it mostly only benefits multisignature users) but since it has no drawbacks with this (i.e. singlesig users can continue to use P2WPKH and P2PKH still) this is still a nice, tidy win!
(even singlesig users get a minor benefit, in that multisig users will now reduce their blockchain space footprint, so that fees can be kept low for everybody; so for example even if you have your single set of private keys engraved on titanium plates sealed in an airtight box stored in a safe buried in a desert protected by angry nomads riding giant sandworms because you're the frickin' Kwisatz Haderach, you still gain some benefit from Taproot)
And here's the important part: if P2PKH/P2WPKH is working perfectly fine with you and you decide to never use Taproot yourself, Taproot will not affect you detrimentally. First do no harm!

Taproot and Your Contracts

No one is an island, no one lives alone. Give and you shall receive. You know: by trading with other people, you can gain expertise in some obscure little necessity of the world (and greatly increase your productivity in that little field), and then trade the products of your expertise for necessities other people have created, all of you thereby gaining gains from trade.
So, contracts, which are basically enforceable agreements that facilitate trading with people who you do not personally know and therefore might not trust.
Let's start with a simple example. You want to buy some gewgaws from somebody. But you don't know them personally. The seller wants the money, you want their gewgaws, but because of the lack of trust (you don't know them!! what if they're scammers??) neither of you can benefit from gains from trade.
However, suppose both of you know of some entity that both of you trust. That entity can act as a trusted escrow. The entity provides you security: this enables the trade, allowing both of you to get gains from trade.
In Bitcoin-land, this can be implemented as a 2-of-3 multisignature. The three signatories in the multisgnature would be you, the gewgaw seller, and the escrow. You put the payment for the gewgaws into this 2-of-3 multisignature address.
Now, suppose it turns out neither of you are scammers (whaaaat!). You receive the gewgaws just fine and you're willing to pay up for them. Then you and the gewgaw seller just sign a transaction --- you and the gewgaw seller are 2, sufficient to trigger the 2-of-3 --- that spends from the 2-of-3 address to a singlesig the gewgaw seller wants (or whatever address the gewgaw seller wants).
But suppose some problem arises. The seller gave you gawgews instead of gewgaws. Or you decided to keep the gewgaws but not sign the transaction to release the funds to the seller. In either case, the escrow is notified, and if it can sign with you to refund the funds back to you (if the seller was a scammer) or it can sign with the seller to forward the funds to the seller (if you were a scammer).
Taproot helps with this: like mentioned above, it allows multisignature setups to produce only one signature, reducing blockchain space usage, and thus making contracts --- which require multiple people, by definition, you don't make contracts with yourself --- is made cheaper (which we hope enables more of these setups to happen for more gains from trade for everyone, also, moon and lambos).
(technology-wise, it's easier to make an n-of-n than a k-of-n, making a k-of-n would require a complex setup involving a long ritual with many communication rounds between the n participants, but an n-of-n can be done trivially with some moon math. You can, however, make what is effectively a 2-of-3 by using a three-branch SCRIPT: either 2-of-2 of you and seller, OR 2-of-2 of you and escrow, OR 2-of-2 of escrow and seller. Fortunately, Taproot adds a facility to embed a SCRIPT inside a public key, so you can have a 2-of-2 Taprooted address (between you and seller) with a SCRIPT branch that can instead be spent with 2-of-2 (you + escrow) OR 2-of-2 (seller + escrow), which implements the three-branched SCRIPT above. If neither of you are scammers (hopefully the common case) then you both sign using your keys and never have to contact the escrow, since you are just using the escrow public key without coordinating with them (because n-of-n is trivial but k-of-n requires setup with communication rounds), so in the "best case" where both of you are honest traders, you also get a privacy boost, in that the escrow never learns you have been trading on gewgaws, I mean ewww, gawgews are much better than gewgaws and therefore I now judge you for being a gewgaw enthusiast, you filthy gewgawer).

Taproot and Your Contracts, Part 2: Cryptographic Boogaloo

Now suppose you want to buy some data instead of things. For example, maybe you have some closed-source software in trial mode installed, and want to pay the developer for the full version. You want to pay for an activation code.
This can be done, today, by using an HTLC. The developer tells you the hash of the activation code. You pay to an HTLC, paying out to the developer if it reveals the preimage (the activation code), or refunding the money back to you after a pre-agreed timeout. If the developer claims the funds, it has to reveal the preimage, which is the activation code, and you can now activate your software. If the developer does not claim the funds by the timeout, you get refunded.
And you can do that, with HTLCs, today.
Of course, HTLCs do have problems:
Fortunately, with Schnorr (which is enabled by Taproot), we can now use the Scriptless Script constuction by Andrew Poelstra. This Scriptless Script allows a new construction, the PTLC or Pointlocked Timelocked Contract. Instead of hashes and preimages, just replace "hash" with "point" and "preimage" with "scalar".
Or as you might know them: "point" is really "public key" and "scalar" is really a "private key". What a PTLC does is that, given a particular public key, the pointlocked branch can be spent only if the spender reveals the private key of the given private key to you.
Another nice thing with PTLCs is that they are deniable. What appears onchain is just a single 2-of-2 signature between you and the developemanufacturer. It's like a magic trick. This signature has no special watermarks, it's a perfectly normal signature (the pledge). However, from this signature, plus some datta given to you by the developemanufacturer (known as the adaptor signature) you can derive the private key of a particular public key you both agree on (the turn). Anyone scraping the blockchain will just see signatures that look just like every other signature, and as long as nobody manages to hack you and get a copy of the adaptor signature or the private key, they cannot get the private key behind the public key (point) that the pointlocked branch needs (the prestige).
(Just to be clear, the public key you are getting the private key from, is distinct from the public key that the developemanufacturer will use for its funds. The activation key is different from the developer's onchain Bitcoin key, and it is the activation key whose private key you will be learning, not the developer's/manufacturer's onchain Bitcoin key).
So:
Taproot lets PTLCs exist onchain because they enable Schnorr, which is a requirement of PTLCs / Scriptless Script.
(technology-wise, take note that Scriptless Script works only for the "pointlocked" branch of the contract; you need normal Script, or a pre-signed nLockTimed transaction, for the "timelocked" branch. Since Taproot can embed a script, you can have the Taproot pubkey be a 2-of-2 to implement the Scriptless Script "pointlocked" branch, then have a hidden script that lets you recover the funds with an OP_CHECKLOCKTIMEVERIFY after the timeout if the seller does not claim the funds.)

Quantum Quibbles!

Now if you were really paying attention, you might have noticed this parenthetical:
(technical details: a Taproot output is 1 version byte + 32 byte public key, while a P2WPKH (bech32 singlesig) output is 1 version byte + 20 byte public key hash...)
So wait, Taproot uses raw 32-byte public keys, and not public key hashes? Isn't that more quantum-vulnerable??
Well, in theory yes. In practice, they probably are not.
It's not that hashes can be broken by quantum computes --- they're still not. Instead, you have to look at how you spend from a P2WPKH/P2PKH pay-to-public-key-hash.
When you spend from a P2PKH / P2WPKH, you have to reveal the public key. Then Bitcoin hashes it and checks if this matches with the public-key-hash, and only then actually validates the signature for that public key.
So an unconfirmed transaction, floating in the mempools of nodes globally, will show, in plain sight for everyone to see, your public key.
(public keys should be public, that's why they're called public keys, LOL)
And if quantum computers are fast enough to be of concern, then they are probably fast enough that, in the several minutes to several hours from broadcast to confirmation, they have already cracked the public key that is openly broadcast with your transaction. The owner of the quantum computer can now replace your unconfirmed transaction with one that pays the funds to itself. Even if you did not opt-in RBF, miners are still incentivized to support RBF on RBF-disabled transactions.
So the extra hash is not as significant a protection against quantum computers as you might think. Instead, the extra hash-and-compare needed is just extra validation effort.
Further, if you have ever, in the past, spent from the address, then there exists already a transaction indelibly stored on the blockchain, openly displaying the public key from which quantum computers can derive the private key. So those are still vulnerable to quantum computers.
For the most part, the cryptographers behind Taproot (and Bitcoin Core) are of the opinion that quantum computers capable of cracking Bitcoin pubkeys are unlikely to appear within a decade or two.
So:
For now, the homomorphic and linear properties of elliptic curve cryptography provide a lot of benefits --- particularly the linearity property is what enables Scriptless Script and simple multisignature (i.e. multisignatures that are just 1 signature onchain). So it might be a good idea to take advantage of them now while we are still fairly safe against quantum computers. It seems likely that quantum-safe signature schemes are nonlinear (thus losing these advantages).

Summary

I Wanna Be The Taprooter!

So, do you want to help activate Taproot? Here's what you, mister sovereign Bitcoin HODLer, can do!

But I Hate Taproot!!

That's fine!

Discussions About Taproot Activation

almkglor your post has been copied because one or more comments in this topic have been removed. This copy will preserve unmoderated topic. If you would like to opt-out, please send a message using [this link].
[deleted comment]
[deleted comment]
[deleted comment]
submitted by anticensor_bot to u/anticensor_bot [link] [comments]

We've officially launched!

We've officially launched!

NextGen P2P cryptocurrency exchange platform
We finally rolled it out!
We did our best to optimize the website’s functionality, …. and simplified registration. With virtually reduced verification procedures you can buy or sell Bitcoin and other cryptocurrency almost instantly using all major payment methods.
In view of recent pandemic and the dire turn the world events are taking, a major episode of inflation awaits most national currencies.
The true impact on the economies hasn’t peaked yet. The worst is still to come and many people realized that. We can see that from the willingness to hedge savings. This idea is gradually gaining traction among public. Increasingly more and more people are thinking of a safe harbor for their assets and many have already turned to digital currency. The testament to this is ever increasing number of crypto wallet addresses.
To help satisfy the growing demand, a project was born to deliver an exchanger where users from anywhere in the world could sell or buy cryptocurrency without paying hefty fees.
Cryptster’s role as a provider of escrow services is to act as a middleman and ensure a fair trade between the two parties.
We decided to give 0% fee grace period to everyone willing to try the product. It’s a perfect chance to get registered and discover true peer-to-peer conversion tool for FREE. There is no commitment, no obligation.

Highlighted features:

  • No mandatory KYC procedures required
  • User-friendly interface
  • Option to enable TOR traffic blocking and 2-Factor Authentication login
  • Free built-in wallet upon registration
  • There is no limit on the number of offers published or the amount traded
  • All withdrawals from the wallet are bolstered with Multisig technology
  • Generation of additional addresses within the wallet for better security
  • Financial data is securely stored in a private blockchain as smart contracts
  • Free and instant asset transfers within the system
  • Adjustable working hours to let other users know when offers are available
  • Two types of chat - Trade and Direct – for in-trade communication and outside it
  • Communication over chat is encrypted and absolutely private
  • Become a Legacy Status holder to enjoy increased trust in your account
  • Flag users as Favorite, Trusted and Blocked, for convenience in future reference
  • Feedback system as user performance indicator
  • User reputation score based on positive/negative feedback
  • and more...
Take advantage of the promotional 0% rate on escrow services while it lasts.
Sign up for free
https://cryptster.io
Happy trading!
submitted by RudeDark to cryptster [link] [comments]

How to verify if a transaction is correctly signed?

Given an arbitrary signed raw transaction, how can we easily verify if all inputs are correctly signed (admiting all UTXOs are present and fee is higher than zero)? I know there is an RPC command in bitcoin core testmempoolaccept but this will also check if all inputs are available to be spent in the mempool/blockchain and I want to test a transaction that is a child to a parent transaction that has not yet been broadcasted.
The signed transaction instance could have the scriptPubKey of the used utxos stored as metadata (since it needs to know these to sign each input) and use the stored utxos to perform this validation - alternatively, the verification method could ask for the scriptPubKeys of the utxos as input. I was looking for some nice way to do this in python but was surprised how neglected this task is:
EDIT: converting to PSBT is not possible/easy so the last option I mentioned won't work. I have the transactions in serialized 'network' format (what you get from `bitcoin-cli getrawtransaction hex')
EDIT2: escalated to bitcoin stack exchange: https://bitcoin.stackexchange.com/questions/96759/how-to-verify-if-a-transaction-is-correctly-signed
submitted by johnturtle to BitcoinBeginners [link] [comments]

How-to: setup your multisignature Cold wallet in Bitcoin Core 0.20 (highest security setup)

Last release of Core is amazing !
The main new feature is sortedmulti descriptor. This allows you to import your multisig setup in Core almost as if it was Electrum when combine to the new PSBT export in GUI !
As it needs command line and some weird checksum, you also need to input very long command in the console and if you made a mistake, you cannot copy the last command you made. So take your time when the commands are long to check everything and don't miss anything, use copy paste before validating the long command. You only have to do this once fortunately :)
I detail here how you do it with a k of n setup, good luck:
And you are DONE ! You should get the exact same addresses than Electrum and you can created receiving addresses in Qt ! To send money, just go to the send section, use the new coin control feature and export a partially signed transaction. You can use HWI or Electrum to sign it with your hardware wallets !
Notice: You can import more or less than 2000 addresses of each type. If less, blockchain rescan is faster but you may need to redo what we have done here later when all addresses will have been used once. If more, it is the contrary.

You now have the most possibly secure setup in one software: multisig with hardware on the full node wallet. When Bitcoin Core 0.21.0 will be out, we will also have native descriptor wallet so maybe we will have HD version of this. But for now, this is the best you can do ! Enjoy :)

P.S. : if you like doing things in one shot you can do the last two steps in one big command: importmulti '[{"desc": "wsh(sortedmulti(k,[path1]xpub1.../0/*,[path2]xpub2.../0/*,...,[pathn]xpubn/0/*))#check_sum0", "timestamp": birth_timestamp, "range": [0,2000], "watchonly": true, "keypool": true}, {"desc": "wsh(sortedmulti(k,[path1]xpub1.../1/*,[path2]xpub2.../1/*,...,[pathn]xpubn/1/*))#check_sum1", "timestamp": birth_timestamp, "range": [0,2000], "watchonly": true, "internal": true}]'
submitted by Pantamis to Bitcoin [link] [comments]

Decentralized payment system NeuronChain presented two new products — NeuronEx P2P-exchange and NeuronWallet digital wallet!

Decentralized payment system NeuronChain presented two new products — NeuronEx P2P-exchange and NeuronWallet digital wallet!
Decentralized payment system NeuronChain presented two new products — NeuronEx P2P-exchange and NeuronWallet digital wallet! ❤️
Transactions with cryptocurrencies and fiat currencies have become even easier — in NeuronChain dPay system, you can use bank cards when buying / selling cryptocurrency. And the network speed has already reached over 100,000 tx/s!
1️⃣. NeuronEx is a P2P Exchange that connects crypto and fiat worlds. It allows to buy, sell or exchange Bitcoin, Ethereum and other cryptocurrencies easily and safely with more than 200 Payment Methods. The platform offers the following advantages: 📷— own coin Neuron (NRON); 📷— direct transfer between the buyer and the seller; 📷— escrow guarantees safe transactions; 📷— the best exchange rate; 📷— more than 200 + payment methods (even with debit/credit cards); 📷— get 50% of any commissions when paying with NRON; 📷— simple registration and 0% Fee Month for trading on NeuronEx; 📷— the opportunity to increase profit through NeuronEx Affiliate Program; 📷— special programs and rewards for NRON holders and traders; 📷— advanced features of order placing and price monitoring.
NeuronEx fully guarantees the security of all cryptocurrency transactions: the payments in cryptocurrency are carried out through an Escrow account, while NeuronEx constantly monitors the fulfillment of all conditions and acts as an independent guarantor.
2️⃣. Neuron Wallet is a decentralized multi-currency wallet, which enables a customer to deposit, exchange and transact with various cryptocurrencies and with fiat funds through embedded fiat cards (in nearest future). The wallet offers the following advantages: 📷— conversion between cryptocurrencies; 📷— trade on the NeuronEx P2P exchange directly from your Neuron Wallet; 📷— conversion from/into fiat money; 📷— transparent cross-border remittance; 📷— guaranteed security (two-factor authentication, multisig and seed-phrases); 📷— anonymity (user data is never stored on the company’s servers); 📷— debit/credit cards support: access to balance information, making transfers, security settings, issuance of new cards; 📷— simplified process of depositing and withdrawing currencies; 📷— crypto API (integration with third-party services, a ready-made solution for online stores, services and portals that need to introduce — cryptocurrency transactions); 📷— usage cryptocurrencies to make everyday purchases with a bank card linked to your Neuron Wallet. Bespoke security for the wallet is guaranteed by private keys that are stored at the user’s end.
Try both http://neuronchain.io
https://preview.redd.it/rowygpu23li51.jpg?width=1200&format=pjpg&auto=webp&s=c2bc353977ea282dae585cada9759e7b33773403
#Finance #NeuronChain #blockchain #NeuronEx #NeuronWallet #CryptoNeuroNews #crypto
submitted by neuronchain to NeuronChain [link] [comments]

Amazing AMA from Douglas Horn

AMA Recap telos Foundation with Crypto Hunters
On August 02, 2020 at 12:00 WIB Indonesia Time / August 01 2020 at 10:00 PM ( PST ) in the Crypto Hunter Telegram Group, AMA TELOS started with Mr.Douglas as guest speaker and Gus Fahlev from Crypto Hunters as moderator. When campaigning, 10 lucky AMA participants when asking questions on Google forms and AMA sessions will get a total TELOS ( TLOS ) prize of $100.
The following is a summary of AMA questions and answers announced by the moderator and
Segment 1
Question 1: Can you explain us, what is Telos?
Answer: Telos is a blockchain platform for smart contracts. It is a low latency—a new block every half second, high capacity—currently in the top 2 blockchains in transactions per day, according to Blocktivity.info, and no transaction fee blockchain. Telos also has many unique features that allow developers to make better, dapps, such as our Telos Decide governance engine.
Question 2: what ecosystem is used by telos?
Answer: Telos is its own Layer-1 blockchain, not a token on another blockchain. The technology behind Telos is EOSIO, the same technology used by EOS and WAX, for example.
Question 3: I see that Telos uses EOSIO platform, what are the very significant advantages that distinguish Telos from other projects?
Answer: Telos uses the EOSIO platform but we have built several additional tools. Some of these add more security and resiliency to the blockchain, such as testing block producers and removing non-performant ones, but most are related to development. Telos provides attractive development tools that aren’t available elsewhere. Telos Decide is a governance platform that lets any group create self-governance tools easily. These run on Telos at very little cost and can provide all kinds of voting, elections, initiative ballots, committee management and funds allocation. Telos also has Telos EVM, an Ethereum virtual machine that can run Ethereum Solidity contracts at hundreds of times the speed of Ethereum and with no costs. Another Telos technology that is deploying soon is dStor, which is a decentralized cloud storage system associated with Telos so that dapps can store files controlled by blockchain contracts.
Question 4: At what stage is Teloa Road Map now? what are the latest updates currently being realized?
Answer: Telos launched its mainnet in December 2018 and has so far produced over 100,000,000 blocks without ever stopping or rolling back the chain. This is likely a record for a public blockchain. We have an ongoing group Telos Core Developers who build and maintain the code and are paid by our Telos Works funding system that is voted by the Telos token holders. Telos is a leader in blockchain governance and regularly amends its governance rules based on smart contract powered voting called Telos Amend. You can see the current Telos governance rules as stored live on the blockchain at tbnoa.org.
The most recent updates were adding new features to Telos Decide to make it more powerful, implementing EOSIO v2.0 which increased the capacity of Telos about 8-10 times what it previously was, and implementing Telos EVM on our Testnet.
We are currently working on better interfaces for Telos Decide voting, and building more infrastructure around Telos EVM so that it is ready to deploy on our mainnet.
Question 5: Is telos currently available on an exchange? and is it ready to be traded?
Answer: Telos has been trading on exchanges for over a year. The largest exchanges are Probit, CoinTiger, CoinLim, and P2PB2B. Other exchanges include Newdex and Alcor. We expect to be listed on larger exchanges in the near future.
Question 6: Now is the time when defi tokens begin to develop, can telos be categorized as a defi project? and what strategies for this year and in the years to come prepared by telos?
Answer: Telos is a smart contract platform, but it already has many DeFi tools built for it including REX staking rewards with a current yield of ~19% APR, smart contract controlled token swaps (like Bancor) with no counterparty called Telos Swaps, a common liquidity pool/order book shared by multiple DEXs to improve liquidity called EvolutionDEX. Wrapped BTC, ETH, XRP, EOS, and other tokens can be brought to Telos and exchanged or used via smart contracts through Transledger. We have more DeFi tools coming all the time including two new offerings in the next few weeks that will be the first of their kind.
Question 7: Governance is an important topic in blockchain and Telos is considered a leader in this area. Why is that?
Answer: Telos is among the top blockchain projects in terms of how it empowers its users to guide the growth of the chain—along the likes of Tezos or new DeFi tokens that offer governance coins. Telos users continuously elect the validating nodes, called Block Producers, that operate the network based on a set of governance documents such as the Telos Blockchain Network Operating Agreement (TBNOA). These are all stored entirely on-chain (viewable at tbnoa.org) and can be modified by smart contract through blockchain voting using Telos Amend. You can see examples of this at https://chainspector.io/governance/ratify-proposals Telos also has a robust user-voted funding mechanism called Telos Works that has funded many projects and is one of the more successful blockchain incubators around. Voting for all of these can be done in a number of ways including block explorers, wallets like Sqrl (desktop) and Telos Wallet (mobile), telos.net and Chainspector (https://chainspector.io/governance/telos-works). But Telos goes beyond any other chain-level governance by making all of these features and more available to any dapp on Telos through Telos Decide governance engine, making it easy for any dapp or DAO to add robust, highly customized voting.
Segment 2 from google form
Question 1: Defi projects are now trending whether telos will also go to Defi projects, to increase investors or the community?
Answer: Yes, we have several DeFi tools on Telos that can work together:
Telos Swaps is an automated, zero-counterparty token swapping smart contract where you can exchange any Telos tokens you may want at any time.
Telos has DEXs and uses a common order book called EvolutionDEX that's available to any DEX so that a buy order on one can be matched against a sell order on another. This greatly increases liquidity for traders.
We have staking rewards though the Resource EXchange (REX) with rewards currently at about 19% APR.
We also have "wrapped" BTC, ETH, and other tokens that can be traded on Telos or used by its smart contracts at half-second transaction times with no transaction fees. This makes Telos a Bitcoin or Ethereum second layer or state channel that's much faster even than Lightning Network and has no fees once the BTC has been brought to Telos.
Question 2: Telos aim is to build a new global economy could you explain how whole ecosystem works? There are already many centralized competitors so what is decentralization aspect in telos?
Answer: Telos is one of the most decentralized blockchain's in the world. It is operated by 51 validators (block producers) who validate blocks in any month. These are voted for on an ongoing basis by Telos account holders.
Telos is also economically decentralized with no large whales like Bitcoin, Ethereum, XRP or EOS because Telos never performed an ICO and limited the size of genesis accounts to 40,000 TLOS max.
Telos is also geographically decentralized with users and block producers on every continent but Antarctica and in numerous countries. The is a large amount in North America and Western Europe, but also in Asia, Australia, and large contingents in Latin America and Africa. Telos has had a Block Producer in Indonesia since the beginning and some dapps on Telos are based in Indonesia as well, like SEEDS, for example.
Question 3: Most investors focus only on the token price in the short term instead of the real value of the project.
Can #TELOS tell me the benefits for investors holding #TELOS the long term?
Answer: That's true about crypto speculators and traders, certainly. Traders are usually looking for coins with good positive momentuum that they hope will continue. But these are often pump and dumps where a few people get in early, pump the price, and then get out at the expense of new investors. That's very unfortunate. Telos isn't like this. One reason is that there aren't large whales who can easily manipulate the price.
Telos seems to be greatly undervalued compared to its peers. Telos has capacity like EOS and well above XRP, XML, Tron, Ethereum. But its value is miniscule relative to these. Telos is a leader in blockchain governance like Tezos but its marketcap is tiny in comparison. Telos onboarded 100,000 new accounts last month and is appearing in the leading crypto press every week with new dapps or developments. So there's some disconnect between the value of Telos and the price. In my experience, these tend to equalize once more people learn about a project.
Question 4: Eos Problems and How Telos Will Solve Them?
Answer: Telos originally set out to solve problems with EOS. It was successful in this and now Telos stands on it's own and our roadmap is more about empowering users. In short, these are some of the EOS problems we already solved:
RAM speculation - Telos had a plan to reduce RAM speculation through a published guidance price that has been extremely successful. The RAM price is guided by market forces but has remained within 10% of the guidance price since launch.
CPU resources - Telos implemented the Telos Resource Improved Management Plan many months ago which was a 7-point approach to making EIDOS-type resource mining unprofitable on Telos. It has largely been successful and Telos has not experienced any resource shortages.
Exchange Collusion/Voting - Telos governance does not permit Exchanges to vote with user tokens. This prevent voting situations seen on EOS or STEEM.
Block Producer collusion - Telos has minimum requirements for block producers and do not allow anyone to own more than one block producer. Those who are found doing so (there have been about 3 cases so far) have been removed and sanctioned in accordance with the rules of the TBNOA.
Question 5: What ecosystems do telos use? and why telos prefers to use EOS network over BEP2 or ERC20? what layer is used telos, can you please explain?
Answer: uses the EOSIO protocol because it is the fastest and most powerful in the world and it also receives the fastest upgrades and ongoing development compared to other blockchain technologies. EOS and WAX also use the EOSIO protocol but they are completely different chains.
Telos is a Layer 1 protocol, meaning that it is its own blockchain that other dapps and smart contracts deploy upon.
One thing that happens when a blockchain like Telos has much, much higher speed and capacity than others like Bitcoin or Ethereum is that Telos can actually run those other blockchains better on its own platform than they can natively. For example, a number of tokens can come in to Telos as wrapped tokens. BTC, ETH, XRP are all current examples of tokens that can be on Telos as wrapped tokens. Once there, these can all be moved around with half-second transaction times and no transaction fees, so they are a better second layer for Bitcoin or Ethereum than Lightning Network or Loom.
Telos can also emulate other chains, which we are doing using Telos EVM which emulates the Ethereum Virtual Machine at about 300 times faster and with no gas fees or congestion compared to Ethereum native deployment. Telos can run Ethereum (Solidity) smart contracts without any changes required. Telos EVM is already deployed on the Telos Testnet and will move to our mainnet soon. So anyone who wants to run ERC-20 tokens on Telos can do so easily and they will be faster and with much less cost than running the same contract on Ethereum.
Segment 3 free asking
Question: I am happy to see new things created by the Telos team. Like What concept did you build in 2020 to make Telos superior?
Answer: Currently, I think Telos Decide is the most unique and powerful feature we have built. There are all kinds of organizations that need to vote. Apartment buildings, school boards, unions, tribes, youth sports leagues, city councils. Voting is hard, time consuming, and expensive for many. Telos Decide makes voting easy, convenient, and transparent. That will be a major improvement and disrupt old style voting. It also goes for buisnesses and corporate governance. Even before COVID it was important, but now people can't really gather in one place so fraud-proof voting is very important. No one has the tools that Telos has. And if they try to copy us, well, we are already way out ahead working on the next features.
Question: If we look about partnerships, Telos has many partnership ! so what's the importance of that partnership for Telos? And How will you protect the value of Telos to your partners or investors ??
Answer: Many of the partnerships are dapps that have decided to deploy on Telos and receive some level of help from the TCD or Telos Foundation to do so. Once a dapp deploys on a chain, it really is like a long term partnership.
Many dapps will become block producers as well and join in the governance of Telos. I suspect that in a few years, most block producers will be the large dapps on the platform with just a few remaining like my company GoodBlock. Of course, we will have our own apps out as well so I guess we'll be developers too.
Telos is very fiscally responsible for investors. We spend little. There has not been any actual inflation on the chain in almost a year. (The token supply has remained unchanged at about 355M TLOS) we are actively working with dapps to bring more to Telos and exchanges and other services like fiat on- and off-ramps to increase value for users.
Question: In challenging crypto market condition any project is really difficult to survive and we are witnessing that there are many platforms . What is telos project plan for surviving in this long blockchain marathon? In this plan, what motivates long term investors and believers?
Answer: True.
While we currently have a low token price, Telos as a DPOS chain can be maintained and grow without a massive army of miners and still maintain BFT.
But the risk is really not whether Telos can continue. Already there are enough dapps that if the block producers went away somehow (not gonna happen) the dapps would just run the chain themselves.
But with 100,000 new users last month and new dapps all the time, we are looking to join the top 5 dapp platforms on DappRadar soon. Survival as a project is not in question.
One of the big reasons is that we never did any ICO and Telos is not a company. So regulatory risks aren't there and there's no company to go bankrupt or fail. We have already developed a bootstrapped system to pay block producers and core developers. So we aren't like a company that will run out of runway sometime.
Question: Could you explain what is DSTOR? What will it contribute to your ecosystem?
Answer: dStor is a decentralized cloud storage system that will have the performance of AWS or Azure with much lower costs and true decentralization. It's based on a highly modified version of IPFS that we have applied for patents for our implementation. It means that dapps will be able to store data like files, images, sound, etc. in a decentralized way.
Question: Trust and security is very important in any business , what makes investors , customer and users safe secure when working with TELOS??
Answer: Telos is decentralized in a way that's more like bitcoin than other blockchains (but without the whales who can manipulate price). There was never any single company that started Telos, so there's no company whose CEO could make decisions for the network. There are numerous block producers who decide on any operational issue that isn't clearly described in the TBNOA governance documents. And to get to an action, 15 of the 21 currently active BPs need to sign a multisig transaction. So that's a high threshold. But also, the TBNOA speaks to a large number of issues and so the BPs can't just make up their own rules.
Since there are really no whales, no one can vote in any kind of change or bring in their own BPs with their votes. This is also very different from other chains where there are whales. Telos is not located in any one country, so our rules can't be driven by one nation's politics.
All in all, this level of decentralization sets Telos apart from almost any blockchain project in existence. People don't have to trust Telos because the system is designed to make trust unnecessary.
submitted by TelosNetwork to TELOS [link] [comments]

Tom Holub of Bit Oasis on Multi-sig Bitcoin Wallets Blockchain - Use cases MultiSignature Wallets a brief intro How To Use Bitcoin Multi-Signature with CoPay How To Create a Secure Multisignature Wallet and Send Multisignature Transactions Multisig para proteger seus Bitcoins

A multisig wallet is one where you need control over multiple private keys in order to spend from that wallet. That is each address in the wallet has multiple private keys behind it. The idea with multisig wallets is that multiple people can cooperatively control the funds in the wallet. Alternatively, the wallet can require approval from multiple devices owned by the same person i.e. a form ... Bitcoin multisig wallets have tremendous potential for increasing the security of funds and giving technology tools to enforce corporate governance. Over the past month we have seen a large number of Bitcoin services dramatically fall over into the abyss. Silk Road 2, the intended successor to the Silk Road anonymous marketplace that was shut down in October last year, lost $2.7 million worth ... The Electron Cash wallet developed by Jonald Fyookball is a fork of Electrum which also offers 2-of-2 multisig options for bitcoin cash users. Armory. Armory is an open source BTC wallet for ... BitGo is a popular Bitcoin wallet which supports multi-signature functionality and has been taking care of Bitcoin funds since 2013. It is also one of the most powerful Bitcoin wallet and API service companies that powers exchanges like ShapeShift, Bitstamp, BitBay, Bitfinex, Kraken, BitQuick, and UnoCoin. You can even integrate your multisig addresses with BitGo along with the Ledger Nano S ... What is Multisig – A Beginner’s Guide. By: Ofir Beigel Last updated: 9/27/20 Multisig is what makes Bitcoin wallets more secure, allows for more corporate use cases, makes trustless escrow/arbitration possible, and generally solves lots of problems. But really, what is it and how do I use it? This post explains it all. What is Multisig Summary

[index] [13536] [15163] [21542] [29387] [38520] [47103] [11893] [27374] [48045] [18060]

Tom Holub of Bit Oasis on Multi-sig Bitcoin Wallets

#Bitcoin #Multisig #Electrum. Category Education; Show more Show less. Loading... Autoplay When autoplay is enabled, a suggested video will automatically play next. Up next Fresh Tutorial of ... Andreas M. Antonopoulos is a best-selling author, speaker, educator, and highly sought after expert in Bitcoin and open blockchain technologies. Andreas has written two best-selling technical ... Whether you want to add security or accountability to your bitcoin transactions or share a bitcoin wallet across multiple device, the BitPay multisignature wallet is a great option. Watch to learn ... Green Address Bitcoin Wallet - Segwit, RBF, 2FA, Multisig and More - Duration: 23:20. BTC Sessions 13,568 views. 23:20. How to create and use Multi Sig Bitcoin Wallets - Duration: 10:23. Hodl Hodl ... How to create and send funds from a multi signature electrum wallet 🎵 Music: Rick Wade - Meditation (Matsa Remix)

#