Merkle Tree - Eine Basis der Blockchain Blockchainwelt

Bob The Magic Custodian



Summary: Everyone knows that when you give your assets to someone else, they always keep them safe. If this is true for individuals, it is certainly true for businesses.
Custodians always tell the truth and manage funds properly. They won't have any interest in taking the assets as an exchange operator would. Auditors tell the truth and can't be misled. That's because organizations that are regulated are incapable of lying and don't make mistakes.

First, some background. Here is a summary of how custodians make us more secure:

Previously, we might give Alice our crypto assets to hold. There were risks:

But "no worries", Alice has a custodian named Bob. Bob is dressed in a nice suit. He knows some politicians. And he drives a Porsche. "So you have nothing to worry about!". And look at all the benefits we get:
See - all problems are solved! All we have to worry about now is:
It's pretty simple. Before we had to trust Alice. Now we only have to trust Alice, Bob, and all the ways in which they communicate. Just think of how much more secure we are!

"On top of that", Bob assures us, "we're using a special wallet structure". Bob shows Alice a diagram. "We've broken the balance up and store it in lots of smaller wallets. That way", he assures her, "a thief can't take it all at once". And he points to a historic case where a large sum was taken "because it was stored in a single wallet... how stupid".
"Very early on, we used to have all the crypto in one wallet", he said, "and then one Christmas a hacker came and took it all. We call him the Grinch. Now we individually wrap each crypto and stick it under a binary search tree. The Grinch has never been back since."

"As well", Bob continues, "even if someone were to get in, we've got insurance. It covers all thefts and even coercion, collusion, and misplaced keys - only subject to the policy terms and conditions." And with that, he pulls out a phone-book sized contract and slams it on the desk with a thud. "Yep", he continues, "we're paying top dollar for one of the best policies in the country!"
"Can I read it?' Alice asks. "Sure," Bob says, "just as soon as our legal team is done with it. They're almost through the first chapter." He pauses, then continues. "And can you believe that sales guy Mike? He has the same year Porsche as me. I mean, what are the odds?"

"Do you use multi-sig?", Alice asks. "Absolutely!" Bob replies. "All our engineers are fully trained in multi-sig. Whenever we want to set up a new wallet, we generate 2 separate keys in an air-gapped process and store them in this proprietary system here. Look, it even requires the biometric signature from one of our team members to initiate any withdrawal." He demonstrates by pressing his thumb into the display. "We use a third-party cloud validation API to match the thumbprint and authorize each withdrawal. The keys are also backed up daily to an off-site third-party."
"Wow that's really impressive," Alice says, "but what if we need access for a withdrawal outside of office hours?" "Well that's no issue", Bob says, "just send us an email, call, or text message and we always have someone on staff to help out. Just another part of our strong commitment to all our customers!"

"What about Proof of Reserve?", Alice asks. "Of course", Bob replies, "though rather than publish any blockchain addresses or signed transaction, for privacy we just do a SHA256 refactoring of the inverse hash modulus for each UTXO nonce and combine the smart contract coefficient consensus in our hyperledger lightning node. But it's really simple to use." He pushes a button and a large green checkmark appears on a screen. "See - the algorithm ran through and reserves are proven."
"Wow", Alice says, "you really know your stuff! And that is easy to use! What about fiat balances?" "Yeah, we have an auditor too", Bob replies, "Been using him for a long time so we have quite a strong relationship going! We have special books we give him every year and he's very efficient! Checks the fiat, crypto, and everything all at once!"

"We used to have a nice offline multi-sig setup we've been using without issue for the past 5 years, but I think we'll move all our funds over to your facility," Alice says. "Awesome", Bob replies, "Thanks so much! This is perfect timing too - my Porsche got a dent on it this morning. We have the paperwork right over here." "Great!", Alice replies.
And with that, Alice gets out her pen and Bob gets the contract. "Don't worry", he says, "you can take your crypto-assets back anytime you like - just subject to our cancellation policy. Our annual management fees are also super low and we don't adjust them often".

How many holes have to exist for your funds to get stolen?
Just one.

Why are we taking a powerful offline multi-sig setup, widely used globally in hundreds of different/lacking regulatory environments with 0 breaches to date, and circumventing it by a demonstrably weak third party layer? And paying a great expense to do so?
If you go through the list of breaches in the past 2 years to highly credible organizations, you go through the list of major corporate frauds (only the ones we know about), you go through the list of all the times platforms have lost funds, you go through the list of times and ways that people have lost their crypto from identity theft, hot wallet exploits, extortion, etc... and then you go through this custodian with a fine-tooth comb and truly believe they have value to add far beyond what you could, sticking your funds in a wallet (or set of wallets) they control exclusively is the absolute worst possible way to take advantage of that security.

The best way to add security for crypto-assets is to make a stronger multi-sig. With one custodian, what you are doing is giving them your cryptocurrency and hoping they're honest, competent, and flawlessly secure. It's no different than storing it on a really secure exchange. Maybe the insurance will cover you. Didn't work for Bitpay in 2015. Didn't work for Yapizon in 2017. Insurance has never paid a claim in the entire history of cryptocurrency. But maybe you'll get lucky. Maybe your exact scenario will buck the trend and be what they're willing to cover. After the large deductible and hopefully without a long and expensive court battle.

And you want to advertise this increase in risk, the lapse of judgement, an accident waiting to happen, as though it's some kind of benefit to customers ("Free institutional-grade storage for your digital assets.")? And then some people are writing to the OSC that custodians should be mandatory for all funds on every exchange platform? That this somehow will make Canadians as a whole more secure or better protected compared with standard air-gapped multi-sig? On what planet?

Most of the problems in Canada stemmed from one thing - a lack of transparency. If Canadians had known what a joke Quadriga was - it wouldn't have grown to lose $400m from hard-working Canadians from coast to coast to coast. And Gerald Cotten would be in jail, not wherever he is now (at best, rotting peacefully). EZ-BTC and mister Dave Smilie would have been a tiny little scam to his friends, not a multi-million dollar fraud. Einstein would have got their act together or been shut down BEFORE losing millions and millions more in people's funds generously donated to criminals. MapleChange wouldn't have even been a thing. And maybe we'd know a little more about CoinTradeNewNote - like how much was lost in there. Almost all of the major losses with cryptocurrency exchanges involve deception with unbacked funds.
So it's great to see transparency reports from BitBuy and ShakePay where someone independently verified the backing. The only thing we don't have is:
It's not complicated to validate cryptocurrency assets. They need to exist, they need to be spendable, and they need to cover the total balances. There are plenty of credible people and firms across the country that have the capacity to reasonably perform this validation. Having more frequent checks by different, independent, parties who publish transparent reports is far more valuable than an annual check by a single "more credible/official" party who does the exact same basic checks and may or may not publish anything. Here's an example set of requirements that could be mandated:
There are ways to structure audits such that neither crypto assets nor customer information are ever put at risk, and both can still be properly validated and publicly verifiable. There are also ways to structure audits such that they are completely reasonable for small platforms and don't inhibit innovation in any way. By making the process as reasonable as possible, we can completely eliminate any reason/excuse that an honest platform would have for not being audited. That is arguable far more important than any incremental improvement we might get from mandating "the best of the best" accountants. Right now we have nothing mandated and tons of Canadians using offshore exchanges with no oversight whatsoever.

Transparency does not prove crypto assets are safe. CoinTradeNewNote, Flexcoin ($600k), and Canadian Bitcoins ($100k) are examples where crypto-assets were breached from platforms in Canada. All of them were online wallets and used no multi-sig as far as any records show. This is consistent with what we see globally - air-gapped multi-sig wallets have an impeccable record, while other schemes tend to suffer breach after breach. We don't actually know how much CoinTrader lost because there was no visibility. Rather than publishing details of what happened, the co-founder of CoinTrader silently moved on to found another platform - the "most trusted way to buy and sell crypto" - a site that has no information whatsoever (that I could find) on the storage practices and a FAQ advising that “[t]rading cryptocurrency is completely safe” and that having your own wallet is “entirely up to you! You can certainly keep cryptocurrency, or fiat, or both, on the app.” Doesn't sound like much was learned here, which is really sad to see.
It's not that complicated or unreasonable to set up a proper hardware wallet. Multi-sig can be learned in a single course. Something the equivalent complexity of a driver's license test could prevent all the cold storage exploits we've seen to date - even globally. Platform operators have a key advantage in detecting and preventing fraud - they know their customers far better than any custodian ever would. The best job that custodians can do is to find high integrity individuals and train them to form even better wallet signatories. Rather than mandating that all platforms expose themselves to arbitrary third party risks, regulations should center around ensuring that all signatories are background-checked, properly trained, and using proper procedures. We also need to make sure that signatories are empowered with rights and responsibilities to reject and report fraud. They need to know that they can safely challenge and delay a transaction - even if it turns out they made a mistake. We need to have an environment where mistakes are brought to the surface and dealt with. Not one where firms and people feel the need to hide what happened. In addition to a knowledge-based test, an auditor can privately interview each signatory to make sure they're not in coercive situations, and we should make sure they can freely and anonymously report any issues without threat of retaliation.
A proper multi-sig has each signature held by a separate person and is governed by policies and mutual decisions instead of a hierarchy. It includes at least one redundant signature. For best results, 3of4, 3of5, 3of6, 4of5, 4of6, 4of7, 5of6, or 5of7.

History has demonstrated over and over again the risk of hot wallets even to highly credible organizations. Nonetheless, many platforms have hot wallets for convenience. While such losses are generally compensated by platforms without issue (for example Poloniex, Bitstamp, Bitfinex, Gatecoin, Coincheck, Bithumb, Zaif, CoinBene, Binance, Bitrue, Bitpoint, Upbit, VinDAX, and now KuCoin), the public tends to focus more on cases that didn't end well. Regardless of what systems are employed, there is always some level of risk. For that reason, most members of the public would prefer to see third party insurance.
Rather than trying to convince third party profit-seekers to provide comprehensive insurance and then relying on an expensive and slow legal system to enforce against whatever legal loopholes they manage to find each and every time something goes wrong, insurance could be run through multiple exchange operators and regulators, with the shared interest of having a reputable industry, keeping costs down, and taking care of Canadians. For example, a 4 of 7 multi-sig insurance fund held between 5 independent exchange operators and 2 regulatory bodies. All Canadian exchanges could pay premiums at a set rate based on their needed coverage, with a higher price paid for hot wallet coverage (anything not an air-gapped multi-sig cold wallet). Such a model would be much cheaper to manage, offer better coverage, and be much more reliable to payout when needed. The kind of coverage you could have under this model is unheard of. You could even create something like the CDIC to protect Canadians who get their trading accounts hacked if they can sufficiently prove the loss is legitimate. In cases of fraud, gross negligence, or insolvency, the fund can be used to pay affected users directly (utilizing the last transparent balance report in the worst case), something which private insurance would never touch. While it's recommended to have official policies for coverage, a model where members vote would fully cover edge cases. (Could be similar to the Supreme Court where justices vote based on case law.)
Such a model could fully protect all Canadians across all platforms. You can have a fiat coverage governed by legal agreements, and crypto-asset coverage governed by both multi-sig and legal agreements. It could be practical, affordable, and inclusive.

Now, we are at a crossroads. We can happily give up our freedom, our innovation, and our money. We can pay hefty expenses to auditors, lawyers, and regulators year after year (and make no mistake - this cost will grow to many millions or even billions as the industry grows - and it will be borne by all Canadians on every platform because platforms are not going to eat up these costs at a loss). We can make it nearly impossible for any new platform to enter the marketplace, forcing Canadians to use the same stagnant platforms year after year. We can centralize and consolidate the entire industry into 2 or 3 big players and have everyone else fail (possibly to heavy losses of users of those platforms). And when a flawed security model doesn't work and gets breached, we can make it even more complicated with even more people in suits making big money doing the job that blockchain was supposed to do in the first place. We can build a system which is so intertwined and dependent on big government, traditional finance, and central bankers that it's future depends entirely on that of the fiat system, of fractional banking, and of government bail-outs. If we choose this path, as history has shown us over and over again, we can not go back, save for revolution. Our children and grandchildren will still be paying the consequences of what we decided today.
Or, we can find solutions that work. We can maintain an open and innovative environment while making the adjustments we need to make to fully protect Canadian investors and cryptocurrency users, giving easy and affordable access to cryptocurrency for all Canadians on the platform of their choice, and creating an environment in which entrepreneurs and problem solvers can bring those solutions forward easily. None of the above precludes innovation in any way, or adds any unreasonable cost - and these three policies would demonstrably eliminate or resolve all 109 historic cases as studied here - that's every single case researched so far going back to 2011. It includes every loss that was studied so far not just in Canada but globally as well.
Unfortunately, finding answers is the least challenging part. Far more challenging is to get platform operators and regulators to agree on anything. My last post got no response whatsoever, and while the OSC has told me they're happy for industry feedback, I believe my opinion alone is fairly meaningless. This takes the whole community working together to solve. So please let me know your thoughts. Please take the time to upvote and share this with people. Please - let's get this solved and not leave it up to other people to do.

Facts/background/sources (skip if you like):



Thoughts?
submitted by azoundria2 to QuadrigaInitiative [link] [comments]

Bitcoin (BTC)A Peer-to-Peer Electronic Cash System.

Bitcoin (BTC)A Peer-to-Peer Electronic Cash System.
  • Bitcoin (BTC) is a peer-to-peer cryptocurrency that aims to function as a means of exchange that is independent of any central authority. BTC can be transferred electronically in a secure, verifiable, and immutable way.
  • Launched in 2009, BTC is the first virtual currency to solve the double-spending issue by timestamping transactions before broadcasting them to all of the nodes in the Bitcoin network. The Bitcoin Protocol offered a solution to the Byzantine Generals’ Problem with a blockchain network structure, a notion first created by Stuart Haber and W. Scott Stornetta in 1991.
  • Bitcoin’s whitepaper was published pseudonymously in 2008 by an individual, or a group, with the pseudonym “Satoshi Nakamoto”, whose underlying identity has still not been verified.
  • The Bitcoin protocol uses an SHA-256d-based Proof-of-Work (PoW) algorithm to reach network consensus. Its network has a target block time of 10 minutes and a maximum supply of 21 million tokens, with a decaying token emission rate. To prevent fluctuation of the block time, the network’s block difficulty is re-adjusted through an algorithm based on the past 2016 block times.
  • With a block size limit capped at 1 megabyte, the Bitcoin Protocol has supported both the Lightning Network, a second-layer infrastructure for payment channels, and Segregated Witness, a soft-fork to increase the number of transactions on a block, as solutions to network scalability.

https://preview.redd.it/s2gmpmeze3151.png?width=256&format=png&auto=webp&s=9759910dd3c4a15b83f55b827d1899fb2fdd3de1

1. What is Bitcoin (BTC)?

  • Bitcoin is a peer-to-peer cryptocurrency that aims to function as a means of exchange and is independent of any central authority. Bitcoins are transferred electronically in a secure, verifiable, and immutable way.
  • Network validators, whom are often referred to as miners, participate in the SHA-256d-based Proof-of-Work consensus mechanism to determine the next global state of the blockchain.
  • The Bitcoin protocol has a target block time of 10 minutes, and a maximum supply of 21 million tokens. The only way new bitcoins can be produced is when a block producer generates a new valid block.
  • The protocol has a token emission rate that halves every 210,000 blocks, or approximately every 4 years.
  • Unlike public blockchain infrastructures supporting the development of decentralized applications (Ethereum), the Bitcoin protocol is primarily used only for payments, and has only very limited support for smart contract-like functionalities (Bitcoin “Script” is mostly used to create certain conditions before bitcoins are used to be spent).

2. Bitcoin’s core features

For a more beginner’s introduction to Bitcoin, please visit Binance Academy’s guide to Bitcoin.

Unspent Transaction Output (UTXO) model

A UTXO transaction works like cash payment between two parties: Alice gives money to Bob and receives change (i.e., unspent amount). In comparison, blockchains like Ethereum rely on the account model.
https://preview.redd.it/t1j6anf8f3151.png?width=1601&format=png&auto=webp&s=33bd141d8f2136a6f32739c8cdc7aae2e04cbc47

Nakamoto consensus

In the Bitcoin network, anyone can join the network and become a bookkeeping service provider i.e., a validator. All validators are allowed in the race to become the block producer for the next block, yet only the first to complete a computationally heavy task will win. This feature is called Proof of Work (PoW).
The probability of any single validator to finish the task first is equal to the percentage of the total network computation power, or hash power, the validator has. For instance, a validator with 5% of the total network computation power will have a 5% chance of completing the task first, and therefore becoming the next block producer.
Since anyone can join the race, competition is prone to increase. In the early days, Bitcoin mining was mostly done by personal computer CPUs.
As of today, Bitcoin validators, or miners, have opted for dedicated and more powerful devices such as machines based on Application-Specific Integrated Circuit (“ASIC”).
Proof of Work secures the network as block producers must have spent resources external to the network (i.e., money to pay electricity), and can provide proof to other participants that they did so.
With various miners competing for block rewards, it becomes difficult for one single malicious party to gain network majority (defined as more than 51% of the network’s hash power in the Nakamoto consensus mechanism). The ability to rearrange transactions via 51% attacks indicates another feature of the Nakamoto consensus: the finality of transactions is only probabilistic.
Once a block is produced, it is then propagated by the block producer to all other validators to check on the validity of all transactions in that block. The block producer will receive rewards in the network’s native currency (i.e., bitcoin) as all validators approve the block and update their ledgers.

The blockchain

Block production

The Bitcoin protocol utilizes the Merkle tree data structure in order to organize hashes of numerous individual transactions into each block. This concept is named after Ralph Merkle, who patented it in 1979.
With the use of a Merkle tree, though each block might contain thousands of transactions, it will have the ability to combine all of their hashes and condense them into one, allowing efficient and secure verification of this group of transactions. This single hash called is a Merkle root, which is stored in the Block Header of a block. The Block Header also stores other meta information of a block, such as a hash of the previous Block Header, which enables blocks to be associated in a chain-like structure (hence the name “blockchain”).
An illustration of block production in the Bitcoin Protocol is demonstrated below.

https://preview.redd.it/m6texxicf3151.png?width=1591&format=png&auto=webp&s=f4253304912ed8370948b9c524e08fef28f1c78d

Block time and mining difficulty

Block time is the period required to create the next block in a network. As mentioned above, the node who solves the computationally intensive task will be allowed to produce the next block. Therefore, block time is directly correlated to the amount of time it takes for a node to find a solution to the task. The Bitcoin protocol sets a target block time of 10 minutes, and attempts to achieve this by introducing a variable named mining difficulty.
Mining difficulty refers to how difficult it is for the node to solve the computationally intensive task. If the network sets a high difficulty for the task, while miners have low computational power, which is often referred to as “hashrate”, it would statistically take longer for the nodes to get an answer for the task. If the difficulty is low, but miners have rather strong computational power, statistically, some nodes will be able to solve the task quickly.
Therefore, the 10 minute target block time is achieved by constantly and automatically adjusting the mining difficulty according to how much computational power there is amongst the nodes. The average block time of the network is evaluated after a certain number of blocks, and if it is greater than the expected block time, the difficulty level will decrease; if it is less than the expected block time, the difficulty level will increase.

What are orphan blocks?

In a PoW blockchain network, if the block time is too low, it would increase the likelihood of nodes producingorphan blocks, for which they would receive no reward. Orphan blocks are produced by nodes who solved the task but did not broadcast their results to the whole network the quickest due to network latency.
It takes time for a message to travel through a network, and it is entirely possible for 2 nodes to complete the task and start to broadcast their results to the network at roughly the same time, while one’s messages are received by all other nodes earlier as the node has low latency.
Imagine there is a network latency of 1 minute and a target block time of 2 minutes. A node could solve the task in around 1 minute but his message would take 1 minute to reach the rest of the nodes that are still working on the solution. While his message travels through the network, all the work done by all other nodes during that 1 minute, even if these nodes also complete the task, would go to waste. In this case, 50% of the computational power contributed to the network is wasted.
The percentage of wasted computational power would proportionally decrease if the mining difficulty were higher, as it would statistically take longer for miners to complete the task. In other words, if the mining difficulty, and therefore targeted block time is low, miners with powerful and often centralized mining facilities would get a higher chance of becoming the block producer, while the participation of weaker miners would become in vain. This introduces possible centralization and weakens the overall security of the network.
However, given a limited amount of transactions that can be stored in a block, making the block time too longwould decrease the number of transactions the network can process per second, negatively affecting network scalability.

3. Bitcoin’s additional features

Segregated Witness (SegWit)

Segregated Witness, often abbreviated as SegWit, is a protocol upgrade proposal that went live in August 2017.
SegWit separates witness signatures from transaction-related data. Witness signatures in legacy Bitcoin blocks often take more than 50% of the block size. By removing witness signatures from the transaction block, this protocol upgrade effectively increases the number of transactions that can be stored in a single block, enabling the network to handle more transactions per second. As a result, SegWit increases the scalability of Nakamoto consensus-based blockchain networks like Bitcoin and Litecoin.
SegWit also makes transactions cheaper. Since transaction fees are derived from how much data is being processed by the block producer, the more transactions that can be stored in a 1MB block, the cheaper individual transactions become.
https://preview.redd.it/depya70mf3151.png?width=1601&format=png&auto=webp&s=a6499aa2131fbf347f8ffd812930b2f7d66be48e
The legacy Bitcoin block has a block size limit of 1 megabyte, and any change on the block size would require a network hard-fork. On August 1st 2017, the first hard-fork occurred, leading to the creation of Bitcoin Cash (“BCH”), which introduced an 8 megabyte block size limit.
Conversely, Segregated Witness was a soft-fork: it never changed the transaction block size limit of the network. Instead, it added an extended block with an upper limit of 3 megabytes, which contains solely witness signatures, to the 1 megabyte block that contains only transaction data. This new block type can be processed even by nodes that have not completed the SegWit protocol upgrade.
Furthermore, the separation of witness signatures from transaction data solves the malleability issue with the original Bitcoin protocol. Without Segregated Witness, these signatures could be altered before the block is validated by miners. Indeed, alterations can be done in such a way that if the system does a mathematical check, the signature would still be valid. However, since the values in the signature are changed, the two signatures would create vastly different hash values.
For instance, if a witness signature states “6,” it has a mathematical value of 6, and would create a hash value of 12345. However, if the witness signature were changed to “06”, it would maintain a mathematical value of 6 while creating a (faulty) hash value of 67890.
Since the mathematical values are the same, the altered signature remains a valid signature. This would create a bookkeeping issue, as transactions in Nakamoto consensus-based blockchain networks are documented with these hash values, or transaction IDs. Effectively, one can alter a transaction ID to a new one, and the new ID can still be valid.
This can create many issues, as illustrated in the below example:
  1. Alice sends Bob 1 BTC, and Bob sends Merchant Carol this 1 BTC for some goods.
  2. Bob sends Carols this 1 BTC, while the transaction from Alice to Bob is not yet validated. Carol sees this incoming transaction of 1 BTC to him, and immediately ships goods to B.
  3. At the moment, the transaction from Alice to Bob is still not confirmed by the network, and Bob can change the witness signature, therefore changing this transaction ID from 12345 to 67890.
  4. Now Carol will not receive his 1 BTC, as the network looks for transaction 12345 to ensure that Bob’s wallet balance is valid.
  5. As this particular transaction ID changed from 12345 to 67890, the transaction from Bob to Carol will fail, and Bob will get his goods while still holding his BTC.
With the Segregated Witness upgrade, such instances can not happen again. This is because the witness signatures are moved outside of the transaction block into an extended block, and altering the witness signature won’t affect the transaction ID.
Since the transaction malleability issue is fixed, Segregated Witness also enables the proper functioning of second-layer scalability solutions on the Bitcoin protocol, such as the Lightning Network.

Lightning Network

Lightning Network is a second-layer micropayment solution for scalability.
Specifically, Lightning Network aims to enable near-instant and low-cost payments between merchants and customers that wish to use bitcoins.
Lightning Network was conceptualized in a whitepaper by Joseph Poon and Thaddeus Dryja in 2015. Since then, it has been implemented by multiple companies. The most prominent of them include Blockstream, Lightning Labs, and ACINQ.
A list of curated resources relevant to Lightning Network can be found here.
In the Lightning Network, if a customer wishes to transact with a merchant, both of them need to open a payment channel, which operates off the Bitcoin blockchain (i.e., off-chain vs. on-chain). None of the transaction details from this payment channel are recorded on the blockchain, and only when the channel is closed will the end result of both party’s wallet balances be updated to the blockchain. The blockchain only serves as a settlement layer for Lightning transactions.
Since all transactions done via the payment channel are conducted independently of the Nakamoto consensus, both parties involved in transactions do not need to wait for network confirmation on transactions. Instead, transacting parties would pay transaction fees to Bitcoin miners only when they decide to close the channel.
https://preview.redd.it/cy56icarf3151.png?width=1601&format=png&auto=webp&s=b239a63c6a87ec6cc1b18ce2cbd0355f8831c3a8
One limitation to the Lightning Network is that it requires a person to be online to receive transactions attributing towards him. Another limitation in user experience could be that one needs to lock up some funds every time he wishes to open a payment channel, and is only able to use that fund within the channel.
However, this does not mean he needs to create new channels every time he wishes to transact with a different person on the Lightning Network. If Alice wants to send money to Carol, but they do not have a payment channel open, they can ask Bob, who has payment channels open to both Alice and Carol, to help make that transaction. Alice will be able to send funds to Bob, and Bob to Carol. Hence, the number of “payment hubs” (i.e., Bob in the previous example) correlates with both the convenience and the usability of the Lightning Network for real-world applications.

Schnorr Signature upgrade proposal

Elliptic Curve Digital Signature Algorithm (“ECDSA”) signatures are used to sign transactions on the Bitcoin blockchain.
https://preview.redd.it/hjeqe4l7g3151.png?width=1601&format=png&auto=webp&s=8014fb08fe62ac4d91645499bc0c7e1c04c5d7c4
However, many developers now advocate for replacing ECDSA with Schnorr Signature. Once Schnorr Signatures are implemented, multiple parties can collaborate in producing a signature that is valid for the sum of their public keys.
This would primarily be beneficial for network scalability. When multiple addresses were to conduct transactions to a single address, each transaction would require their own signature. With Schnorr Signature, all these signatures would be combined into one. As a result, the network would be able to store more transactions in a single block.
https://preview.redd.it/axg3wayag3151.png?width=1601&format=png&auto=webp&s=93d958fa6b0e623caa82ca71fe457b4daa88c71e
The reduced size in signatures implies a reduced cost on transaction fees. The group of senders can split the transaction fees for that one group signature, instead of paying for one personal signature individually.
Schnorr Signature also improves network privacy and token fungibility. A third-party observer will not be able to detect if a user is sending a multi-signature transaction, since the signature will be in the same format as a single-signature transaction.

4. Economics and supply distribution

The Bitcoin protocol utilizes the Nakamoto consensus, and nodes validate blocks via Proof-of-Work mining. The bitcoin token was not pre-mined, and has a maximum supply of 21 million. The initial reward for a block was 50 BTC per block. Block mining rewards halve every 210,000 blocks. Since the average time for block production on the blockchain is 10 minutes, it implies that the block reward halving events will approximately take place every 4 years.
As of May 12th 2020, the block mining rewards are 6.25 BTC per block. Transaction fees also represent a minor revenue stream for miners.
submitted by D-platform to u/D-platform [link] [comments]

Weekly Update: ParJar media blitz, Fiat pegged tipping goes live, Hydro Community Content Initiative, Sentivate Ambassadors... – 15 Nov - 21 Nov'19

Weekly Update: ParJar media blitz, Fiat pegged tipping goes live, Hydro Community Content Initiative, Sentivate Ambassadors... – 15 Nov - 21 Nov'19
Sup folks! This is the final one of the catch up series. Here’s your week at Parachute + partners (15 Nov - 21 Nov'19):

With the latest update in ParJar, you can now tip crypto to your friends pegged to fiat. For example, if you were ever stuck on “How do I send $PAR tokens worth 10 USD to Cap?”, you can now simply type “/tip 10 USD PAR” and boom! ParJar does the rest for you. Awesome isn’t it? Last week we didn’t even notice that ParJar had been featured on a number of crypto publications. Cap found out this week. From Decrypt to TronWeekly to BitcoinExchangeGuide, ParJar made a big splash everywhere. Friggin amazing! PAR4PAR lottery entered stage 7. 350k $PAR up for grabs. Charlotte's Math trivia in TTR was super fun. 10 questions, 2500 $PAR each. Doc Vic (from Cuba) made a group for CoD Mobile players from Parachute. Join in if interested.
No more wondering “How much is 5 USD in $PAR?” when tipping. Yay!
In this week’s creative contest (@captainparachute #fanciness) by Jason, Parachuters had to “draw fancy outfits for captain”. Tons of $PAR given out for making Captain fabulous. Haha. Weekly Parenas are back. This week’s Parena saw Carlos take home a cool 25k $PAR from the 50k $PAR pot by beating Brian in a quick finale. This week’s Two-for-Tuesday’s theme was live in concert bands. An epic Tuesday ensued. In this week's #PFFL update, Hang (9-2) has moved to first place with Clinton following closely at 8-3. Chris, Alexis and Andy are in third position with 7-4. For #wholesomewed this week, Parachuters shared pivotal events from their lives that made them what they are. As a Helium hotspot operator, Cap and Ice travelled to a meetup this week in NYC to explore synergies.
Peace Love’s late entry for last week’s #Parichristmas. Can you identify the face? Haha
Catch up on the latest at aXpire from CEO Gary Markham’s inaugural State of the Market episode. Plus, there’s the Week 46 update video by Joakim as well. This week’s 20k $AXPR burn can be tracked here. Do you work at a Law firm that is looking to improve profitability? Look no further. Bilr is here to help. Have a read of this article to know more. The ERC20-BEP2 swap bridge is now back online. Check out the cool new promo video of the 2gether card. Founder Salvador Casquero will be part of a webinar discussion with Manager Focus on digital currencies on the 28th. Mark your calendars! CEO Ramón Ferraz's full interview with Emprendiendo.TV from South Summit which happened several weeks back was published this week. He also wrote about DeFi (Decentralised Finance) and its impact on the financial sector in a recent CryptoDaily UK article. The story behind the present branding of XIO can be read in this tweet thread. A new gif contest was started just before of the reveal of the first set of nominated startups for the XIO incubator. Hope you had a chance to make a submission. The Birdchain community was invited this week to vote for their favorite entry in the Copywrite Challenge. Voting will be open till the 27th. Plus, a new referral bonus was started. Woot woot! Did you know that you could earn 5% interest for holding $ETHOS on Voyager? Read more about it here. The latest update of the Voyager app was released this week.
Thanks for making this ParJar branded coupon/label, Jose. I can already see so many uses for this
Tron is now live on the Switch-backed McAfeeDex. Its volume on the SwitchDex network can also be tracked from DappRadar. The Dex supports 70 languages as of now and will become as close to a DAO as possible by decentralising decision making from 2020. Mineable featured Fantom $FTM in his list of 7 promising cryptos video. If you are looking to stake $FTM when mainnet goes live, make sure to read this article to understand how it will work. For the latest roundup from Fantomverse, click here. And welcome to the $FTM fam, Samuel! The voting for the #UptrenndOC contest finalists was conducted. BeInCrypto joined Uptrennd this week. $1UP is now listed on P2PB2B exchange. The crew will be covering CoinPoint's Annual VIP Networking Party next year as a media partner. Congratulations to the winners of the ETH Prediction contest for winning 2k $1UP tokens. Sweet! Part I of the Uptrennd Sharing Contest got off to a roaring start. For the latest scoop on District0x, check out the District Weekly. The District Registry article in the education portal has been updated in preparation of its launch. How to win over customers in the Fintech space? Hydro breaks it down for you in this article. The Hydro Community Content Initiative looks at creative inputs from the community to spread the word on Hydro. The project won an international competition called APIficator hosted by Sia Partners at The Met in NYC. APIficator is an open innovation challenge that looks for the best banking and finance APIs from around the world. Woohoo! As Vault prepares for a 2020 launch, here’s a quick product update.
Views from the Hydrogen HQ are to die for
If you want to see Silent Notary’s $SNTR token listed on Halodex, then don’t forget to vote for IDLedgers in the Halodex Listing Contest. Interested to become a Sentivate Ambassador? Get in touch with the crew. There will also be an Advocate Program for busy folks. Following the community's vote from a few weeks back to have more ELI5 content on core web technologies in video format, the team announced that they will be starting a podcast soon from their new office in Pittsburgh. Scott Melker (The Wolf Of All Streets) joined as an advisor to the project this week. Stay tuned to the upcoming AMAs to get in on exclusive updates. One of them will have more details on Artifacts. OST CEO Jason Goldberg wrote in depth about how OST’s tech makes Pepo such a powerful app. Pepo also got covered in detailed articles on Cointelegraph and Blockchain.news. Decrypt also did a brief feature of $OST. A Merkle Tree is a data structure that allows for quick verification in a large amount of data. SelfKey team published an article that explains how Merkle Trees make blockchains efficient. They also put together an eye-opening list of major data breaches in 2019. But what do hackers do with the breached data? Click here to find out. Busy week at Pynk with the crew travelling to Expanse Summit to speak on "Investing with AI" and then to Shift Conference in Croatia (where they made it to the finals) followed by FintechMatters in Vienna (where co-founder Mark Little talked about Crowd Wisdom) and finally to Slush in Helsinki (for biz dev).
Signing up for Pepo is pretty straightforward
Shuffle Monster’s $SHUF token is now a default token on Uniswap. Wibson team attended the Games Changer Summit hosted by Forbes Argentina this week. Head of Research Carlos Sarraute travelled to the University of San Andrés to train attendees on Big Data and talk shop. Read up on the Wibson journey so far from this article. Harmony had proposed a new staking mechanism called Effective Proof-of-Stake (EPoS) back in August. This week, it started to come to fruition with the latest commit. Click here to see what it takes to get it live. Harmony's Java SDK was released as well. Digital marketer Nick Vasilich shared his learnings from working on the development of Harmony DAO from the ground up. To stay upto date with Harmony news in your local language, don’t forget to follow the regional accounts. Welcome to Harmony, Wen! In this week's Harmony Insights episode, we learnt about market making. $ONE was listed on DeFi platform Constant which enables P2P lending. On that occasion, a special deal of lower interest rates for borrowing against $ONE was announced. Click here for pictures from Binance Turkey meetup that Harmony crew visited. Continuing from last week’s Harmony Bytes, the challenges of staking were discussed in the latest episode. As mentioned last week, the team was in Odessa as part of #CryptourUkraine. Next week, Vinnytsia.

And with that, we are 100% updated with the latest week. Yay! See you again with another weekly update. Ciao!
submitted by abhijoysarkar to ParachuteToken [link] [comments]

My Intern Experience

My Intern Experience
Shreemoon Rajbhandari
My Intern Experience
During my time as an undergraduate, one of the key experiences recommended is to do an internship. Gaining work experience as an intern overseas will improve a skill set in my area of interest. Working somewhere as culturally different and economically significant as China is a talking point in any interviews. There are many reasons that made me choose to do an internship in China. Definitively the best part of the experience has been living out of your comfort zone. Encountering new situations and experiences, that increase my self awareness, my capabilities and also to discover my weaknesses.
Over the past 2 years, we have seen many digital currencies/cryptocurrencies being introduced globally.These have added the aspect of using this financial ecosystem to eventually solve social issues. This could be the application of Blockchain technology in areas like logistics/supply chain to food security. Eventually, there would be many more areas where blockchain and related technology developers would be needed. It's emerging to change the way we solve the many roadblocks that we face.
Blockchain is considered to be one of the most trending topics. This is the right time for me to learn about the technology and start implementing. Blockchain is a notion that can be implemented directly or indirectly to any sector as such. Only two months prior, I had a minimal amount of knowledge about blockchain innovation, and my insight into blockchain comprised distinctly of an obscure comprehension of bitcoin and cryptographic money all in all.
During my internship, I was given investigation material to help assemble my base comprehension of Loopring and the blockchain innovation that it depends on. In the wake of beginning at Loopring, I have been given significantly more prominent chance to learn. While my comprehension of blockchain is still new, it has improved extensively since my first day at the organisation.
In this post, I would like to talk about two cryptographic methods aiming to give privacy to blockchain technology ; the zk-SNARKS and zk-STARKS protocols are two significant examples. We will look into their advantages and disadvantages, comparison between two protocols, and conclusion.
ZK-SNARKS vs ZK-STARKS
Along with the countless benefits of the Internet from which we can benefit, when we use it for social media or business company purposes, privacy is at greater risk. Approximately 90 million of Facebook users information were damaged by Cambridge Analytical data. The Wall Street stated that “ this is just the beginning, and the results are expected to grow”. The Equifax data breach revealed information on social media channels from private users. Thus, birth dates were exposed to the majority of the populations. Due to the Uber hack, data from over 55 million customers were also shared and exposed.
Privacy has consistently been seen as a valuable element within the cryptocurrency community. There is always a growing focus on improving privacy within the cryptocurrency space. Bitcoin, Ethereum, Litecoin and many other cryptocurrencies are all actively searching for the most convenient approaches to increase their security. It is the antecedent to fungibility, which is vital for a broadly used form of money. Additionally, most crypto-asset holders do not want their transaction history to be completely public to the world. Among the different cryptographic methods aiming to give privacy to blockchain technology; the zk-SNARK and zk-STARKS protocols are two main significant examples.
Two leading technologies today offer their cryptocurrencies - Monero and zcash— and strive to address protection issues. Monero uses the technology of Ring Confidential Signature. By contrast, Z-Cash uses zk-SNARK( Zero-Knowledge transparent knowledge argument), a technology that provides the ability to conduct anonymous transactions.
In recent years, zk-SNARKS has exploded as the most promising technology to solve blockchain privacy. It is a technology derived from proofs of zero-knowledge, a type of proof that anyone with a verification key can check this “proof” without disclosing the information itself. If the statement holds, a verifier will be convinced by a correct proof. If the statement is false, it is true that no prover can convince a verified statement.
zk-SNARK stands for :
- Zero-knowledge : if the statement is true, there is nothing the verifier learns beyond the fact that the statement is true.
- Succinct : The proof size needs to be small enough in a few milliseconds to be verified.
- Non-interactive :Only one set of information is sent to the verifier for verification, therefore there is no back and forth communication between the prover and verifier.
- Argument of Knowledge : A computationally soundproof: soundness runs counter to a prover leveraging polynomial-time, i.e. limited computing. Also, Without access to the witness (the private input needed to prove the statement), the evidence can not be constructed.
zk-SNARKS aims to provide fast, scalable solutions to ensure financial security. Therefore, transaction encryption is possible.When zk-SNARK is applied to a cryptocurrency, it implies you can conceal the majority of the transaction data information. This incorporates the sender address, collector address, just as the transaction sum amount. zk-SNARKS enables us to shroud the majority of this data information, while likewise enabling the system to affirm and verify the transactions. It amplifies security while maintaining consensus. In the realm of blockchain, it is one of the most exceptional blockchain level protection innovation being used.
With the launch of version 3.0, Loopring’s decentralised protocol solution struck a noteworthy milestone in early May- adding off-chain scaling and fee optimisation using zk-SNARKs. Low fees, liquidity, transparency and security are the key goal of the loopring solution. Loopring says the new Loopring 3.0 based zk-SNARK will increase trade speeds and on-chain activity efficiency tenfold. The data previously stored on-chain in Loopring 3.0 is now stored off-chain in a Merkle tree and then used as required in zk-SNARKS, updating the tree.
Be that as it may, there are a few issues with zk-SNARKS. The main problem has been the need for a trusted setup. zk-SNARKS rely on a permission private key. This essentially undermines the entire purpose of decentralised public blockchain. By introducing the need to trust a person rather than code, you threaten the entire concept of trustlessness. In theory, a prover with sufficient computational power could create fake proofs, and this is one of the reasons why many consider quantum computers as a threat to zk-SNARKs (and blockchain systems).
Last year zk-SNARKS were incorporated on a MIT Tech Review list of the top 10 Breakthrough Technologies of 2018 among AI advancements. zk-SNARKS allows both a tremendous speedup in verifying the correctness of a computation while at the same time it hides the private details from prying eyes. Some of the potential uses citied in MIT article were verifying you’re over 18 without having to share your date of birth, and providing you have a enough money in your back account as collateral without having to give away account details like your exact balance. It establishes trust which you need to interact on the blockchain. Zk-SNARK proofs are as of now being used on Zcash, on JP Morgan Pursue's blockchain-based payment system, and as an approach to safely validate customers to servers.
The more developed version of zk-SNARKS is called zk-STARKS which stands for :
Zero-Knowledge
Scalable
Transparent
Argument of Knowledge
zk-STARKS verifications are currently being touted as the better than ever form of the convention, tending to a considerable lot of the past disadvantages of zk-SNARKs. It has demonstrated an approach to accomplish a similar degree of privacy as zk-SNARKS without the requirement for the trusted setup. Starks are practically superior to Snarks as they require weaker crypto suppositions, they don't require a trusted setup and are post-quantum resistant. zk-SNARKs are based on Elliptic-Curve Cryptography, which is susceptible to advances in Quantum-Computers. zk-STARKs, on the other hand are Post-Quantum system meaning that even if Quantum-computers become powerful and ubiquitous they will not have an advantage, compared to classical computers, in breaking zk-STARKs. Anyway they have a noteworthy downside, as in the proof being too enormous. Their problem is their storage requirements. STARKs are doubly scalable, which means the proof verification is exponentially faster than the original computation’s time but the drawback is the size of the proof they create being too large, possibly 2 or 3 orders of magnitude more than those produced by zk-SNARKs. One example : StarkWare solves the inherent problems of scalability and privacy of blockchains. Using STARK technology, they generate a full proof-stack to produce and verify computer integrity tests. They utilise STARKs to batch transactions into a single proof that is verified on Ethereum. Matt Taylor states that the present iteration of StarkDEX demonstrates the viability of using STARKs for the scalability of Layer-2 by showing a substantial rise in the amount of blockchain transaction.
The idea of zk-STARKS was proposed by Eli-Ben Sasson, a professor at the Technion-Israel institute of Technology. zk-STARKS provide proofs that can be verified a lot quicker than zk-SNARKS. At the present time, Z-cash and Ethereum are on the whole considering to utilize zk-STARKS. zk-STARKS have solved the trusted setup issue. They have totally expel the requirement for multiple parties to create the private key required for the string. Rather everything needed to produce the proofs is public and the verifications are generated from arbitrary numbers. zk-STARKS actually removed the necessity in zk-SNARKS for unbalanced cryptography and rather utilizes the hash fuctions like those found in Bitcoin mining. In addition, they ought to have longer timeframe of realistic usability as far as their crytographic resilience than zk-SNARKS. However, there are some impediment of zk-STARKS, the main issue with zk-STARKS is their size. The verifications it uses are basically too enormous to use in many blockchains as they stand. As indicated by Vitalik Buterin, zk-STARKS will result in proofs of a couple of hundreds kilobytes versus the 288 bytes seen in zk-SNARKS.

The Difference Between zk-STARKS and zk-SNARKS.

https://preview.redd.it/k1fap29yd4m31.png?width=411&format=png&auto=webp&s=769ef7be2646a2d0ac31a5334f7e7249e2e2e246

Source : The Medium - Coinmonks
The complexity of communication : With the computation’s expanded complexity, the zk-SNARKS communication complexity also increases linearly, whereas zk-STARKs develops in the opposite direction and grows slowly as the computation size grows.The graph above shows that the communication required by the zk-STARKs to complete the calculation rises much slower than zk-snarks as the underlying evidence increases in complexity.

Source : The Medium - Coinmonks
The complexity of the verifier : zk-STARKs slightly widening with the development in computation size. On the other side, for confirmation evidence, zk-SNARKs requires less time than zk-STARKs. zk-STARKs, for instance need up to 100 ms to verify and zk-SNARKs need only up to 10ms. The graph above illustrates the the time taken by the zk-STARK to verify an evidence rises very slowly compared to the zk-SNARK as the underlying evidence increases in complexity.

Overall these two protocols have excellent potential in the cryptocurrency globe and can be a breakthrough avenue for mainstream implementation. Both conventions are truly needed steps to protect our privacy.


Reference
https://www.technologyreview.com/lists/technologies/2018/
https://www.google.co.uk/amp/s/themerkle.com/mit-review-acclaims-zk-snarks-but-zk-starks-may-steal-the-show/amp/
https://ethereum.stackexchange.com/questions/59145/zk-snarks-vs-zk-starks-vs-bulletproofs-updated
https://www.binance.vision/blockchain/zk-snarks-and-zk-starks-explained?amp=1
https://applicature.com/blog/blockchain-technology/can-zk-snarks-and-zk-starks-solve-privacy-issues
https://eprint.iacr.org/2018/046.pdf
https://medium.com/coinmonks/zk-starks-create-verifiable-trust-even-against-quantum-computers-dd9c6a2bb13d
https://blog.0xproject.com/starkdex-bringing-starks-to-ethereum-6a03fffc0eb7
submitted by Shreemoon to loopringorg [link] [comments]

Binance Coin and Ravencoin Surge! Bitcoin Megabulls, Nexo, and More! Crypto News ETHEREUM (ETH) VE BITCOIN (BTC) NEDEN YÜKSELİYOR? Piyasadan haberler Binance Exchange App Review - Part 2 HOW TO TRADE ON BINANCE (EASY STEPS) Bitcoin: My 400 bitcoin bet paid off, but is it too late for others? - BBC News ¡Increíble Hack de 7 mil Bitcoins a Binance solo costo 69$! Merkle Trees & Patricia Tries for Blockchain - Explained Live Trading Bitcoin di Binance Futures - Bitcoin ... Bitcoin, Sex, & Drugs - Crypto Burning Man - Bitcoin & Cryptocurrency News Merkle Trees - Efficient Data Verification

This entry was posted in Bitcoin News, BitcoinNews.com, Blockchain, cartoon, Cartoon Corner, Cryptocurrency, merkle, merkle tree, News on January 24, 2019 by adminbtc. Email* September 2020 Bitcoin News. Google News Bitcoin; Bitcoin.com; Cryptocoins Exchanges. Coinbase ; Kraken ; CEX.IO; Binance In Bitcoin, there are several vulnerabilities regarding privacy as the use of mixers and ring signatures are limited to a finite number of transactions. Whereas, in Zcoin a privacy-coin that uses the unique ‘Zerocoin’ protocol is used containing zero-knowledge proofs enabling scalable privacy to the many thousands of transactions. Merkle Tree – Definition und Nutzen. In der Kryptographie und Informatik ist ein Hash-Baum oder Merkle-Tree ein Baum, in dem jeder Blattknoten mit dem Hash eines Datenblocks und jeder Nicht-Blattknoten mit dem kryptographischen Hash der Labels seiner Kindknoten beschriftet ist.. Hash Trees ermöglichen eine effiziente und sichere Verifikation der Inhalte großer Datenstrukturen. News and updates from the world’s leading cryptocurrency exchange. Blog > Binance Academy Q&A Bounty . Jun 23. 2020. Binance Academy Q&A Bounty. Since the beginning of Binance Academy, the Academy team has been working hard to produce educational material to help increase the adoption and understanding of cryptocurrency and blockchain technology. In addition to writing articles, we are now ... Although Bitcoin was the first blockchain to implement Merkle trees, many other blockchains implement similar Merkle tree structures or even more complex versions. Further, Merkle tree implementation is not only limited to blockchains and is applied to a variety of other systems.

[index] [20083] [9709] [21461] [20398] [17855] [23541] [1948] [18310] [10497] [20446]

Binance Coin and Ravencoin Surge! Bitcoin Megabulls, Nexo, and More! Crypto News

24/7 Live Bitcoin Algo Trading on Deribit Exchange (DeriBot) Bitcoin Trading Robots 254 watching Live now The Untold Truth About Money: How to Build Wealth From Nothing. Binance (Biggest in world!) ... Bitcoin 101 - Merkle Roots and Merkle Trees - Bitcoin Coding and Software - The Block Header - Duration: 24:18. CRI 42,505 views. 24:18. Dan's Intro to How Ethereum ... Binance Vadeli işlemler %10 komisyon indirimli referans adı: turkey Binance Vadeli işlemler direk kayıt linki: https://www.binance.com/en/futures/ref/turkey ... A walk through of the AWESOME! Binance App for your Mobile! It allows you to trade on the go, how good is that! Use my ref link below, if you want to help me out! Beginners Exchange Coin Spot - 50 ... This Bitcoin millionaire who lives in tree house - Duration: 1:49. CNBC Television 726,810 views. 1:49. The biggest bitcoin news of the year, says Brian Kelly - Duration: 6:15. ... Live Trading Bitcoin di Binance Futures - Bitcoin Indonesia #1 bitcoin indonesia. Loading... Unsubscribe from bitcoin indonesia? Cancel Unsubscribe. Working... Subscribe Subscribed Unsubscribe 733 ... Ravencoin and Binance Coin are surging and Mattie will tell you why! He will also talk about bullish bitcoin prediction, Nexo lending platform, as well as our 1 year anniversary. ----- Connect ... About Merkle Trees, used for Efficient Data Verification. In today's episode Nick... branches out and discusses Merkle Tree, that's all I've got for this one. ===== I'm not a financial adviser. Do ... Los mercados están bastante agitados con los tweets de Trump o por hacks y noticias inesperadas en el crypto y Bitcoin, en este caso un hackeo sopresivo al exchange binance, cobro mas de 7 mil ... Bitcoin and cryptocurrency news - Millenials love Bitcoin.....surprise! Uganda gets Binance, Bitcoin and the sex drugs nexus, no rock and roll, sorry! Crypto Giveaway 10,000 Adbank - 6 lucky ...

http://binance-review.forex-club.club