The New York-based bitcoin exchange Gemini has announced the introduction of zero-confirmation pre-credited cryptocurrency deposits.The feature will allow users to immediately trade their funds without waiting hours for the first confirmation.The move is aimed at reducing deposit delays that have often been a problem for bitcoin users.With the growing volume of bitcoin transactions and fixed network capacity, it can take much longer time for the transactions to be confirmed.“At Gemini, we pride ourselves on helping you move your money faster,” said Eric Winer, VP of engineering at Gemini.“Our unique Instant ACH system lets US-based customers deposit U.S.dollars and trade immediately, a process that used to take up to a week.” “Last year, we decreased the required number of Bitcoin confirmations for deposits from six to three.And we continue to have industry-leading turnaround times for U.S.dollar wire deposits and withdrawals,” Winer said.With the new feature, Gemini will start crediting customers before the confirmation has occurred on the blockchain.

As the company explained, it will use a proprietary fee algorithm to find out the likelihood of each deposit to be confirmed.If it meets the criteria, the company will pre-credit the amount of the transaction in the customer’s account, thus making it available for trading.Users will be able to sell bitcoin for USD or ether much more quickly and efficiently.Furthermore, the company will let customers to take part in Gemini’s daily two-sided auction without delays.After a deposit gets three confirmations, users will be able to withdraw the amount of the deposit or any USD or ether acquired with the deposit.In addition to the zero-confirmation deposits feature, the company also introduced some changes to their Instant ACH deposit option, Winer wrote.“Instant ACH is one of our most popular features, and after listening to your comments and feedback over the last year, we’ve made some changes to how we calculate your “Available for Withdrawal” balance.We think you’ll find the new system much more sensible — especially if you make frequent deposits and trades,” he said.

The new feature is one of the latest moves the company have taken to attract more customers.Not long ago, Gemini announced the expansion to Japan and the Republic of Korea as part of its strategy to build a global next generation bitcoin exchange.The company is committed to provide an increased level of security for its clients.A few days ago, it published a blog post encouraging its users to switch to the Authy app for two-factor authentication (2FA) instead of using SMS.As Gemini noted, the app significantly reduces the risk of hacker attack.Founded in 2015, Gemini is among the few companies that were granted a virtual currency and money transmitter license by the New York Department of Financial Services.Just two weeks ago, one of the major bitcoin firms, Coinbase, also got the department’s approval.Our service provides financial guarantee for transactions with no need to be concerned about block inclusion time and potential double spend.GAP600 enables bitcoin users to experience bitcoin like they experience all other digital services – without delay.

We analyze and score every single bitcoin transaction on the network and we guarantee the value of that transaction regardless of whether it’s included in a block.bitcoin atm explainedFEATURES We are insured - GAP600 Ltd technology is insured by USA based underwriter Proprietary real-time risk engine analyzing and confirming bitcoin transactions Robust Infrastructure in a secure environment Pay as you go & discounted Enterprise packages API-based connection Flexible risk management subscriptions ADVANTAGES No need to wait for block inclusion - transactions confirmed within seconds Transactions guaranteed against double-spend or fraud Improve user experience and boost activity - resulting in increased revenue Mitigation of transaction and treasury risk for unconfirmed transactions Real-time clarity for blockchain applications PLATFORM OVERVIEW GAP600 bridges the gap from the time the transaction is published on the bitcoin network until it joins the block chain.bitcoin lagos

A Bitcoin transaction can fail to confirm, or become “stuck,” for a number of reasons.Stuck transactions are usually confirmed after several days, but sometimes waiting isn't an option.bitcoin lagosFortunately, many stuck transactions can be cleared using nothing more than a Web browser.bitcoin wpaThis article shows how.bitcoin escrow scriptThe procedure described here should not be used by beginners trying to clear a stuck transaction of significant value.bitcoin url poolDoing so can lead to loss of money.ethereum upgradeThis article describes a practical technique for creating and clearing a stuck transaction, but using this technique effectively takes practice and understanding.double vpn bitcoin

To get the most out of it, consider following the article as written and only commit a trivial amount of money.If any step describes a concept that doesn't make sense, find a way to understand it.bitcoin cosa sonoLeave a comment at the bottom of the article.Ask a knowledgeable friend.Post a question to BitcoinBeginners, Bitcoin Subreddit, or Bitcoin Stack Exchange.Whatever happens, be sure you undertand, at a high level, the procedure described here before using it to clear a high-value transaction.The most common cause for a stuck transaction is that it carries a fee that was set too low.Bitcoin fees are a complicated topic, but the most important number to keep in mind is your transaction's fee density.Fee density is calculated by dividing the transaction fee (in satoshis) by the length of the transaction (in bytes).Fees make up a tiny fraction of miner revenue today, but miners already act as if they‘re trying to maximize revenue from fees.

The process begins by isolating transactions that don’t qualify for a fee waiver.These transactions are then sorted by fee density.Next, the transaction with the highest fee density is added to a candidate block.Then the transaction with the second highest fee density is added, and so on.When block capacity exceeds transaction demand, all waiting transactions can be added to a candidate block.But during times of high transaction volume such as those that have recently taken place, then some transactions will be left behind.To a first approximation, miners don't consider the time a transaction has already waited.This means that newer transactions can cut to the front of the line if they have a higher fee density than yours.The problem is a bit like a diver collecting items from the bottom of a lake.High density items thrown in will sink to the bottom and will be eventually be collected.Less dense items won‘t sink to the bottom and so can’t be collected no matter how many of them are thrown in.

The technique we'll use to clear the stuck transaction is known as double spending.Double spending occurs when the same coin is spent more than once.Recall that Bitcoin is an electronic cash system in which users move value around by transferring ownership of digital tokens called “coins”.A successful double spend invalidates a stuck transaction, thereby clearing it.Double spending an unconfirmed transaction is conceptually the same thing as double spending a confirmed transaction, but orders of magnitude easier.Specifically, we'll be relying on a mode of operation known as First-Seen-Safe Replace-by-Fee (FSS RBF).In a nutshell, FSS RBF is a node policy that replaces one unconfirmed sibling with another, provided that the second sibling pays a higher fee and routes payments through all of the same addresses.The best time to learn how to clear a stuck transaction is before it becomes critical to do so.This section describes how to place a dummy transaction into limbo so that it can later be cleared.

Stuck transactions are easiest to create during times of high transaction volume.One way to determine if this condition holds is to use a fee monitoring tool such as Cointape.Begin by creating two key pairs.The first will serve as a source and second will serve as a destination for a transaction with an uncompetitive fee density.This can be done by opening a browser tab and loading Bitaddress.Generate two unencrypted addresses without artwork.Route four payments totaling ฿0.001 through the first address using transactions with high fee density.Alternatively, a four-output transaction can split payments totaling ฿0.001 among the same address.Copy the first address to the clipboard, and keep Bitaddress tab open.The purpose of making four payments is to later produce a child transaction that can easily be given a fee density of approximately 1 satoshi/byte and an absolute fee of 1,000 satoshis, the minimum required for transaction relay.Open a new browser tab and load the Blockchain block explorer.

Paste the address you copied into the search box and click the button labeled “Search.” Wait until refreshing the page shows that all four deposits received at least one confirmation.Keep this tab open.After your deposits have been confirmed, create a transaction that spends them with a fee density close to 1 satoshi/byte.To do so, open a third browser tab and load Coinbin.Coinbin is a convenient tool for creating custom transactions.Load Coinbin’s Transaction page by selecting the “Transaction” option from the tab labeled “New.” Begin by pasting the address on the clipboard into the first field of the Coinbin Transaction page.Click the button labeled “Load.” After a few seconds, you should see a message informing you that unspent outputs have been retrieved.Next, copy the payment address from the Bitaddress tab (it should be the second one listed).Return to the Coinbin tab, then scroll down until a field labeled “Address” becomes visible.Paste the payment address into the text field.

Use an amount of ฿0.00099.The field directly below the payment address, labeled “Transaction Fee,” should read ฿0.00001.If network transaction volume is too low, a fee of zero satoshis can be set by spending the entire balance on the sending address.Generate the unsigned transaction by pressing the button labeled “Submit.” Copy the raw hex bytes to the system clipboard.The transaction can now be signed.Scroll to the top of the Coinbin page, then click the “Sign” tab.Paste the raw transaction bytes into the second text area.From the Bitaddress browser tab, copy the private key for the first address.Then open the Coinbin tab and paste this private key into the field labeled “Private key.” Generate the signed transaction by pressing the button labeled “Submit.” A new section labeled “Signed transaction” should appear.If signed correctly, the transaction’s hex byte sequence should be longer than the hex byte sequence of the unsigned transaction.Next, copy the hex byte sequence of the signed transaction.

The signed transaction can now be published.Scroll to the top of the Coinbin page and click the tab labeled “Broadcast.” Paste the signed transaction raw hex bytes into the text area.Publish the transaction by clicking the button labeled “Submit.” Coinbin should present a success message with the transaction’s ID.Confirm that your new transaction has propagated by clicking on the Blockchain browser tab.After refreshing the page, a second transaction should appear.Click on the transaction ID link, and verify that the amount of the transaction and fee are ฿0.00099 and ฿0.00001, respectively.The latter value is 1,000 satoshis.Dividing it by the size of the transaction in bytes should give a number just over 1, the minimum fee density required by the network.This transaction may be confirmed as you’re completing the next steps.However, if you‘re performing this test during a time of high transaction volume, it’s likely to remain stuck for several blocks at least.Checking for the transaction ID on several block explorers is informative.

Some block explorers may not report having seen the transaction, a consequence of poor network propagation.That‘s what we’re aiming for.Having produced a stuck transaction, its double spending sibling can now be created.Return to the Coinbin browser tab.Click on the “New” tab and select the “Transaction” option.Coinbin should have remembered the information you previously entered.All that’s needed is to update the payment amount.Replace it with ฿0.0006.Coinbin should simultaneously update the fee to ฿0.0003, a 70-fold increase.Scroll down to the button labeled “Submit” and press it.Coinbin should update the raw transaction byte sequence.Copy the new raw byte sequence, scroll to the top of the page, and then click the “Sign” tab.Sign the double spending transaction as before.Replace the existing raw byte sequence with the one you just copied.There should be no need to update the private key.Scroll to the bottom of the page and click the button labeled “Submit.” Coinbin should update the signed transaction byte sequence.

We can’t publish this new transaction using Coinbin because it will be rejected as a double spend.Instead, we need to find another node that will accept it.A list of “pushtx” URLs can be found on the Bitcoin Wiki.As of mid-2015, one of the pushtx services listed there was found to accept transactions of the kind we're about to publish, the Localbitcoins block explorer.Open a new browser tab to this page.Now publish the sibling transaction by pasting the raw transaction bytes into the text field and click the button labeled “Send transaction.” If successful, you’ll receive a message along with a new transaction hash.Verify the propagation of the sibling transaction by opening a new browser tab pointing to Blockchain.Paste the ID for the sibling transaction into the search box.A transaction summary page should appear.Double spending should be indicated with two warning messages in red.You should see confirmation of the sibling transaction within one or two blocks.Localbitcoins may stop accepting transactions of the kind you've just created at some point in the future.

If this happens, a new service will need to be found.A starting point would be to try each service listed on the Bitcoin Wiki page.Alternatively, Bitcoin XT nodes relay double spends.If you can connect to one, it should relay the sibling transaction for you.The above procedure exposes private keys to a network-connected computer.To avoid this unsafe practice, an alternative signing procedure can be used.This procedure is identical to the original, except that the signing step is performed on an offline computer.Begin by creating an offline copy of Coinbin.Download the offline bundle by clicking on the “download” link at the bottom of the Coinbin home page.Save the archive file to a trustworthy removable medium.To run Coinbin offline, boot into an offline session.Open your removable medium and extract the Coinbin archive.Coinbin can be run offline by clicking on the file named index.html in the coinbin-master folder.Using this setup, transactions can be created online, saved to a removable medium, signed offline, then published online.