texts: Is there any chance of the Ripple gateway market NOT consolidating into a small transnational oligopoly?

texts: Bigger and better reputations might beget more business and so on. What can possibly prevent emergence of a small oligopoly of transnational Ripple gateways ?


texts: Step by Step to Connect to ElectrumX via Nodejs

texts:
I am developing a simple app that will need to retrieve BTC wallet Address Balance and relative transactions

Initially I thought to use some existing APIs (btc.com, blockchain.com etc.), but the limitation in terms of request rates do not fit my project...

Looking at other options it seems that my best bet is:

Identify an ElectrumX public server
Request blockchain.scripthash.get_balance (via JSON RPC)
Request blockchain.scripthash.get_history (via JSON RPC)

now, I am not a techy person, but I like to learn and play around :) therefore I need to "translate the theory into practice"... where do I start? is there a step by step guide "for dummie" tutorial?

Thank you all


texts:
I installed electrum created my fist wallet and notice that instead of having to save a wallet.dat file, If I am right I just need to save/write  12 seed words.

If I understand properly the seeds used to create the wallet, will always produce the same output, but how does the recover process works in order to restore/recover the wallet balance?

Is the blockchain checked against my wallet keys to claim ownership of the transactions that where signed with my keys in order to recover the possible founds?


texts:
Did the developers of the various premined coins have to wait for those coins to be mined first or did they change the code to first issue themselves the premined coins?

I'm referring to the list of coins at http://altcoins.com/scamcoins


texts: How to fork blockchain intentionally without RPC commands?

texts:
Are there any methods other than RPC command invalidateblock <hash> for creating forks?
I know that forks occur when two miners (nearly) simultanously each generate a block for a previous common block but is this the only natural way to fork the blockchain?

I want to test blockchain forks with multiple nodes and would like to have one node intentionally create forks from time to time. How can I achieve this? Do I need to make all nodes generate blocks simultanously and hope that randomly two or more blocks are created at the same time? - This would lead to a mess, right?


texts: How vulnerable is bitcoin to quantum algorithms?

texts:
Assuming that quantum computers are implemented some time in the near-ish future, how vulnerable is Bitcoin to decryption via quantum algorithms? For example, Shor's algorithm enables a quantum computer to prime factorize in polynomial time. A variant of it can crack ECDSA.
However, Bitcoin relies on a scripting system, so if quantum computers are created, one probably can just switch to a secure script1
Is Bitcoin vulnerable to attacks from quantum computers? Are these vulnerabilities fixable2?
1.  Then again, there are limits to scripting and quantum computing may make it impossible for any script to work.
2. "Fixable" can both be client-side fixable, where everyone just tweaks the script they use and transfers all their money to a clean set of addresses (thus securing all their bitcoins with the new script), or protocol-side fixable, where the protocol is tweaked and everyone downloads a new client. The latter is nor preferable, since the old bitcoins will probably be lost in the process.


texts: Do all Bitcoin alternatives need to have a coin limit?

texts:
In the Netherlands, it was just in the news the e-gulden was launched.
Before we got the Euro (€) we had that currency in our country.

An E-gulden (EFL) is currently 50 EFL = €1,50

But is there for any cryptocurrenty a limit? Or could the creators just create as many as they like?

I know that Bitcoin has a maximum coin limit.


texts:
Well, bit coin mining is looking more and more promising and to be honest, i don't know a lot. I heard you get a lot from AMD cards, but if i use my Nvidia card will it even be worth it? Thanks in advance!

Also, is there a guide to start mining? like a beginners guide for retards?

edit: By worth it i mean will my power bill be more than what im earning, or have they come up so much that its not a big deal?


texts: Get input addresses of a transaction using electrum

texts:
I am using the latest (3.2.3) command line version of Electrum. I want to find the inputs of a transaction by looking at the history. The previous version of Electrum (that I was using 8 months ago) had a field (array) called input_addresses in its history output.

The current version does not have it.

A sample output from history is something like this:

$ electrum --testnet history --show_addresses | tail -40
...
        {
            "balance": "xxx BTC",
            "confirmations": 1,
            "date": "2018-09-21 12:27",
            "height": 1413976,
            "inputs": [
                {
                    "prevout_hash": "c96274d67e095...74c1af",
                    "prevout_n": 1
                },
                {
                    "prevout_hash": "f7e443ade3f0e...fe1eb8",
                    "prevout_n": 0
                }
            ],
            "label": "",
            "outputs": [
                {
                    "address": "myAB...",
                    "value": "0.49794855 BTC"
                },
                {
                    "address": "2N25...",
                    "value": "5.000258 BTC"
                }
            ],
            "timestamp": 1537522037,
            "txid": "3404f9fb96...0d253c",
            "value": "-5.00233525 BTC"
        }
    ]
}

So I am left with something called inputs containing some hashes. I need to convert these hashes to input addresses from command line.

The GUI version of Electrum will show the input address on the right of the hashes, like this:

c96274d67e095...74c1af:1    mhAhgR...
f7e443ade3f0e...fe1eb8:0    mhAhgR...


texts: Can't Make Sense of Why OP_CHECKSIG Fails Here


texts: Why is the Bitcoin blockchain designed so that a block can be unconfirmed?

texts: I have a basic question about blockchain and Bitcoin.  After a transaction is confirmed and included in a  block, it is said to have a depth (confirmation) of one.  However I've read that many companies require "multiple" confirmations (up to 6) before they consider a transaction truly confirmed.  Does that mean that a block taht is confirmed can be revoked, thus nullifying the previously confirmed transaction?  What purpose would such a behavior serve -- in other words, once a transaction is confirmed and a block is formed, what advantage is there to later "unconfirmed" taht block?


texts: Bitcoin QR codes: raw address or Bitcoin URI scheme

texts:
I am the author of bitcoinaddress.js library and I am wondering what's the best content for Bitcoin QR codes.

What Bitcoin QR codes should contain (for mobile wallet apps and other barcode scanners):

Only Bitcoin address (this is only one I have seen wild myself)
Bitcoin URI scheme link (BIP 21) with payment amount, transaction note, etc.

Currently I implemented address only, as I don't know how well-spread BIP 21 support is among the mobile phones and mobile wallets. If anyone can give me some answers and pointers to the prior research regarding the matter I'd be grateful.


texts: How can transactions be verified without the private key?

texts:
Trying to get my head around her royal Bitcoin here...

I understand that blocks of transactions are broadcast to the network, and that miners verify that the BC is 'spendable' by trawling the blockchain and following the wallet address's transaction history (or at least I assume that's how it works).

But how does one actually verify that the BC transaction has been signed by it's owner when the miners don't have access to the private key? To put it simpler, how can verification take place without processing both the public and private keys?

I'm probably misunderstanding PKI encryption, but (say) with SSH, the private key would be on a trusted server and verification would take place on that server. How can that possibly work in a distributed network?


texts: I want my money i used the recommended fees for my 3 transfers but we going on 36 hours and no confirmation

texts: i did use the suggested fee from block-chain and still nothing what do i do .........decentralized currency is awesome but who is responsible when shit hits the fan if my bank was to mess up and not get my transfer lost i could call the bank and be fixed right away now im out my funds for going to be 3 days and no end in sight b41a9804a2e131196717b550553804dad75baec2e43a4817e6b1ba7cb2a12895   8d5e0ebff08ffd3ce6c4c4224a56d4e2458623476a21cb3ab732e2817a278f0b            00afdc1da94fd08b79e084c0ce60c5c97647e55ec9e8cef9dcc85aa1a4f44532


texts: Did Satoshi Nakamoto (in his blogs or the whitepaper) forecast that mining pools would exist?

texts:
Mining pools are common today where users pool their resources together and share profits accordingly. Such pools today can account for significant proportions of a network's hash power and they're are risks shold a coalition of malicious parties form a pool with 51% of the mining power.
My question is, did Satoshi ever forsee this coming or consider it as a possibility that may arise? Did Satoshi ever provide any thought about the positive/negative implications of the existence of mining pools?


texts: After reading that Mining involves Taking a root hash of a transaction and combining that hash with a nonce it is required to find a number that is equal or below the given target, i was wondering if you have to try different orders of hashing the transactions or you just hash them all at once. For example does it make a difference if i hash a transaction A first and then transaction B or B first and then A.


texts: how to transmit commitment transaction (unilateral close) from lightning network channel

texts: How would you transmit a commitment transaction from a lightning network channel instead of closing the channel? I am working on implementing a watchtower and I first need to simulate a double spend attempt. When I close a channel with $ lncli closechannel, both nodes have the bitcoin available and neither has to wait for the time lock. Is there a command to get the node to submit a unilateral close commitment transaction where one of them has to wait for the time lock?


texts: How the first succesful miner is ensured his reward

texts: With my still rather limited knowledge of bitcoin, I was wondering how the correct origin of proof of work is ensured. Specifically, when a miner successful computes a valid hash and is to broadcast this to others, how can he be sure that others do not alter the block now that they know the hash, rewarding themselves instead of the original successful miner?


texts: How can a DAO seek enforcement of a contract?

texts:
If a DAO hires someone to perform a task that is not completed according to contract terms, what is the legal remedy of the DAO.

Assuming the DAO is not incorporated in any jurisdiction, can DAO members vote to appoint an agent to use the courts to seek enforcement on their behalf? Will the courts recognize the legal standing of this agent?

Please use any jurisdiction you can to cite a means of a DAO enforcing a contract.


texts: I'd like to experiment with different minimum difficulty settings for my p2pool miners to see if I can get more shares per block. Does anyone have a formula or any recommendations for a minimum difficulty level, based on the GH/s available and the current share difficulty?


texts: What is the safest method managing a large number of receiving Bitcoin addresses?

texts:
Say I want to run a big project, where users can continually request new addresses to deposit Bitcoins in their online account. I suppose I will have to pre-generate thousands of Bitcoin key-pairs and import them into a running instance of bitcoind on my server. Each time a user requests a new address to deposit Bitcoins into his account, I will assign him a new address. Then bitcoind will notify me when any of the imported addresses receive a transaction.

First question: Is bitcoind capable of monitoring thousands of addresses in real-time? Should I plan a dedicated machine for this?

Second question: Since I will need to move received Bitcoins to a cold storage and also make payouts automatically many times a day, I will need to store the private keys on the online server as well. I can have wallet.dat password-protected but what is the safest method to automatically unlock the wallet, move funds and then lock it again without the password being possibly compromised? I don’t consider it safe if the password appears anywhere in code, config or database. And I don’t want to enter the password manually several times a day.

Third question: Will bitcoind generate a new “change address” every time I move funds from the receiving address to payouts and cold storage? I ask because if bitcoind used one of the imported addresses for change, it would appear as if client received Bitcoins.


texts: What is an extended fingerprint (xfp) and how does it differ from an xpub?

texts:
Coldcard requires the xfps of all of its cosigners to be able to verify and sign multisig transactions. Providing the coldcard with just the xpubs is not enough, which I believe to mean that the xfp can't be gleaned from the xpub.

So, what is an xfp and how does it differ from an xpub?


texts:
I am building a simple p2pkh transaction using libbitcoin. Trying to pass it through my regtest node. I am getting the following error message.

error code: -26
error message:
16: mandatory-script-verify-flag-failed (Signature is found in scriptCode)

my transaction hash is as below:

01000000018df8ae6050992976497b63349c281bd05666842a6a82d6d8b26dc51812d58201000000006b483045022100c4befe583a3bc22eeaf1516c6d26fb3e1240bdfdf25db266494d82c77ccb36100220108ad79c4a34115eec23f5b0202d492dd88ec637df17a1982d4a63382e457599012102a018e21c743a4b67dcf38f9b693e807b1fbb833dfe705aa513abbf177b04adc2ffffffff01c0a6b9290100000017a91450628702abb40cc5fee219b9c834f4126c4198848700000000

Can anyone suggest what is happening here??

Please let me know if more information is required to understand the problem.

Thank you.


texts: Historical intraday data for altcoins that can be exported?

texts:
I've been looking around lately for historical data, like opening price, closing, high, low etc for altcoins. All I have come up with is daily data or higher, but what I need is like 5, 10, 15 minutes etc.

I need to be able to have data for at least a few weeks back. And I need to be able to export it as a CSV file or something.

Any ideas?


texts: What are the bitcoin dependencies for red hat linux? Bitcoin fails to compile

texts:
I'm using CentOS on my server, and when I try to compile bitcoin from the github source using make -f makefile.unix, I get a ton of errors. I'm assuming they're caused by dependency errors?

I've seen a bunch of dependency lists for debian-based linux distros which use apt-get, but I'd like to know what I need for CentOS. Installing the dependencies from the debian lists using yum show the packages as unavailable.

Here's the huge error list, if anyone wants it: http://pastebin.com/1y2wCH5N


texts: Does bitcoin still concatenate the locking and unlocking script and execute?

texts: Does bitcoin still concatenate the locking and unlocking scripts and execute in order to validate transaction or is validation done another way?


texts:
Suppose I have a random transaction which I recovered from blockchain blk****.dat file.

How can I calculate the number of confirmations of this transaction? I dont want to use the RPC call getrawtrasaction.


texts:
As describe by Maxwell here in HD wallets assuming we have a key pair with private key SK.a and public key of PK.a and a seed s and a generator point G, we can generate a new key pair of (SK.b, PK.b) as follows:

PK.b = PK.a + sG
SK.b = SK.a + s

The advantage with this method is that a service provider can generate new public keys without knowing the clients private key.
My question is that, why don't we multiply the seed and private key rather than adding them?

PK.b = PK.a * s
SK.b = SK.a * s

Is there any problem with the later method that I suggested?


texts: Are Bitcoin's blocks signed by the miner?

texts:
To my understanding, at no point in the Bitcoin Whitepaper does it say that blocks are signed by the miner. However, one could see the advantage of having blocks signed.
Thus I wonder if in the implementation of Bitcoin, blocks are signed by miners? Or maybe I missed it in the Whitepaper?
Thanks!


texts:
Aside from learning about all of bitcoin just for fun (mathematician with spare time), I currently own some bitcoin IOU's via Robinhood, but I would like to actually own my bitcoin (my keys, my coins! As they say).
I have been investigating Coinbase and hardware wallets like Nano Ledger S.
My understanding is that Coinbase is an exchange or market place where BTC can be bought and sold, but also offers wallet services.
My understanding of a hardware wallet like Nano Ledger S is that it is a very secure hardware device (cold storage, meaning completely offline) that will store the public and private key to my BTC wallet - and the private key to my wallet is synonymous with the bitcoin I hold. It has a 20 word mnemonic so if I hypothetically lost the device, I could buy a new one and access my wallet using the 20 word mnemonic. (I would also like to understand how buying a new Nano Ledger S and entering my mnemonic allows it to essentially restore to my old wallet, it seems like this would require the information to be stored somewhere. But I'll save that for a different question later on)
If my understanding above is correct, I would like to now understand the way transactions take place between the two concepts listed above.

I purchase X BTC on coinbase and it goes to my "hosted wallet" on Coinbase (X used as a variable representing the amount of BTC)
I can send the X BTC I purchased to my hardware wallet by giving the public key to my hardware wallet and specifying perhaps .99X BTC go to that wallet and the remaining .01 BTC is left as the transaction fee.
Coinbase broadcasts the transaction in the P2P network, sent around through full nodes in the network.
When this transaction gets grouped into a block and is mined, my wallet now contains .99X BTC meaning my public key shows up somewhere on the blockchain ledger that I have .99X unspent BTC associated to my public key.

I can repeat this process as many times as I like, continuing to accumulate more BTC in exchange for USD via Coinbase.

Eventually, maybe I want to liquidate some BTC in exchange for USD.
I can do this by using Ledger Live as described on the
ledger website here. Is this still "offline"? even when I "unlock and connect" my ledger device?
I use ledger live to send BTC to my Coinbase "hosted wallet" public key. When the transaction is processed I can sell my BTC on Coinbase market at the market value.

Is my understanding correct? And if so, how is my private key being used when I send BTC using ledger live? I think it is used to "sign" the transaction? So in some way is my private key vulnerable to nano ledger programming or software when sending?
I understand this is very amateur material, I have tried hard to learn on my own without asking here, but the quality of answers on this site, so far, have proven better than anything I have found on my own.


texts: I downloaded the original bitcoin wallet for the mac in 2014. I purchased my first BTC around that date and I simply did not keep my wallet synched and up to date. I attempted to download the blockchain from bitcointalk.org and it did not work. However, after downloading, my wallet now says I have 0.0 BTC available and 0.0BTC pending. However, on the right side you can still see the transaction history from when I originally bought the BTC and it shows the full amount there. Is my BTC permanently gone? How can I retrieve my BTC and synch my wallet to the current blockchain? Any help would be great and I would even be willing to send some BTC as a reward to anyone who can help me retrieve my BTC.


texts: Bitcoin hard disk replace to a solid disk

texts: So, i might change my hard drive disk to a solid disk on my mac. Before I do that, what should I do to have my bitcoins safely saved from the hard disk to the solid disk once I install the solid disk in my mac?


texts: What exactly happens when I import private keys to my wallet?

texts:
I can create addresses with private keys and import those keys into my wallet to receive their unspent outputs to later spend.

My question is split into two parts:

What exactly happens when you import a private key? Is that private key now stored and its corresponding address now tracked by your wallet?
A new transaction is signed with a private key. Therefore, if I have 1 BTC on one address and import its private key, and 1 BTC on another address and import that, how is it I can now spend 2 BTC in one transaction, which key was used to sign this new transaction?


texts: Do private people mining or exchanging Bitcoin with Fiat fall under FINCEN's definition of "user"?

texts:
Fincen's March 2013 report defines:

A user is a person that obtains virtual currency to purchase goods or services.
An exchanger is a person engaged as a business in the exchange of virtual currency for real currency, funds, or other virtual currency.
An administrator is a person engaged as a business in issuing (putting into circulation) a virtual currency, and who has the authority to redeem (to withdraw from circulation) such virtual currency.

Note that to in order be considered an exchanger or administrator by the above definition, a person must be "engaged as a business".

So, is it true that a private person who mines at home, or a private person that sells Bitcoins in exchange for fiat, isn't in fact considered an exchanger or administrator, but rather a user (and is therefore not a Money Service Business and is exempt from regulation)?


texts: How does MPOS communicate with stratum server?

texts:
I'm setting up MPOS. There are 3 stratum server options: stratum-mining, NOMP, and CoiniumServ. How does MPOS talk with stratum server? AFAIK, MPOS does not speak stratum protocol. Is it through the shared mysql database, where stratum server writes to it (e.g., submitted shared) and MPOS retrieves from.

I'm trying to use a stratum server other than the 3 options above, thus trying to see how to make it compatible with MPOS.


texts: I'm Studying bitcoin from a while, focusing transaction model and I'm looking to extract transaction model only to try out some experiments to make the structure better from the current one. If anyone can guide me through, that will be very helpful.


texts: What is the maximum number of bits mining hardware ever needs to hash at one time?

texts:
What would be the max number of bits that hashing hardware specifically designed for bitcoin mining would ever need to hash per operation?  For example:

block header = 80 bytes = 640 bits
after first hash = 256 bits

To find merkle root:   256(per txn) x 2 = 512 bits

So is 640 bits the max input message size the hashing hardware needs to handle?


texts: What was the vulnerability in v0.3.4 that allowed an attacker to steal coins?

texts:
Reference: http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2010-5141

What was the specific exploit in the Tx script evaluation process?


texts: Electrum on Android - where is wallet.dat hidden?

texts:
Does anyone knows where Electrum android app saves its wallet.dat on phone/sd memory?
If such files exists is it possible to transfer it between phones?
I have forgotten my seed words (and do not want to move btcs from wallet to another) and wonder if this is an option to transfer this file like on desktop (with wallet.dat file)


texts: BTC transaction is slow now. How come when buying at Exchange, it's immediate?

texts:
On Exchange, when buy or sell, it's immediate.
Isn't transaction is supposed to be ledger by Blockchain?
Does that mean my BTC account at Exchange are all not ledger yet. How legitimate is my BTC at Exchange then?
My understanding is when I withdraw BTC to my cold storage, that's the time it is ledger by Blockchain and it usually take some time. Am I correct?


texts: I know GPU mining is looked down upon, but I cant afford an ASIC. SO I would like to know how to mine Bitcoin with CGminer using my gpu. Any help would be appreciated. I already am connected to a server, so I don't need help with that.


texts:
I am new to trading. On the left side is the order book and on the right, the trade history.

I can see that the order book keeps updating. The number in the market size column increases and decreases, but I don't see any update in the trade history. May I know why? Does the trade history only reflect part of all trades?


texts:
Anyone know how / where to run

enum optypecode

(or some other method) to get a list of current opcodes? Like this result...

https://www.slideshare.net/gvrooyen/20140220-bitcoin/34-We_just_used_4_opcodesenum


texts: Is there a deterministic private-public keypair generator without the BIP32 private key revealing issue?

texts:
HD Wallets have a flaw that revealing a private key and its parent master public key will reveal its parent master private key. (Described here[1] and here[2]).

Isn't there a similar concept with master public key and master private key that does not suffer from this issue. (Does not have to be ECDSA. I just want a deterministic private-public keypair generator that can publish its master public key).

[1] https://bitcoinmagazine.com/8396/deterministic-wallets-advantages-flaw/

[2] https://eprint.iacr.org/2014/998.pdf (chapter 3)


texts: If bitcoins can be stolen via hacking, what's there to stop these already occurring events and bitcoins from falling right back into the hands of power. I mean bitcoins are capable of being untraceable. So who's to say that its NOT already being utilized as the new, maybe even world, currency for control?


texts:
So we're all aware of services like CoinAd, but what if someone took advantage of that? Imagine if someone had a video game on facebook or something and had people fill out a CAPTCHA before they could play... couldn't someone really just ajax a separate, custom server that curl'd coinAd, kept the session alive, passed the image generated by google to the user, have them fill it out, then pass the answer back to coinAd, and inserting their own BTC address? Couldn't someone decieve people into giving them a BTC charity?

I know it's "limited" to one address per hour per user or whatever, but if you played it smart, you could have thousands of addresses and make thousands of users with thousands of email addresses. You could even shard the servers around the world so that you won't have one ip address. Heck, I bet you could even put it on the user's own computer in an  with display:none!

Although coinad's rate is only .00005 BTC (~1/1000th of $0.01), but if you get 20,000 users on your facebook game, you'd make $100.

What I'm saying is, is it illegal to take advantage of this (technically speaking) give-away? ;)


texts:
I am running a node on Windows Server 2016.
Everything seems to be running fine.

If I go to https://bitnodes.earn.com/ and put myip:8333, the node is successfully reachable.

My bitcoin.conf is:
    server=1
    txindex=1
    rpcuser=...
    rpcpassword=...

Locally, I can access it:

bitcoin-cli.exe -rpcuser=... -rpcpassword=... getinfo

returns:

{
  "deprecation-warning": "WARNING: getinfo is deprecated and will be fully removed in 0.16. Projects should transition to using getblockchaininfo, getnetworkinfo, and getwalletinfo before upgrading to 0.16",
  "version": 150001,
  "protocolversion": 70015,
  "walletversion": 139900,
  "balance": 0.00000000,
  "blocks": 0,
  "timeoffset": 0,
  "connections": 16,
  "proxy": "",
  "difficulty": 1,
  "testnet": false,
  "keypoololdest": 1506982194,
  "keypoolsize": 2000,
  "paytxfee": 0.00000000,
  "relayfee": 0.00001000,
  "errors": ""
}

However, any C# bitcoin lib I tried always returns the same web exception when trying to connect to bitcoind:

"The underlying connection was closed: The connection was closed unexpectedly."

and, also, I do not understand why some samples use port 8332, some 8333, etc. I don't have anything listening to 8332.

What could I be missing?


texts: The order of the generator point G used in bitcoin

texts:
Hi I was just wondering how the order of the generator point G used in bitcoin was actually calculated.

From the specification listed http://www.secg.org/SEC2-Ver-1.0.pdf for secp256k1 I can see listed is the generator point G along with its order, however I am unsure how this was actually calculated.

In one of the books I was looking through it was mentioned that Hasse's Theorem was used to calculate this value, however upon looking up this theorem this seems to only provide a bound. Any insight would be appreicated thanks :)


texts: How to get BTCChina full Orderbook (FIX or alt API)

texts:
I have worked through BTCChina's FIX APi (using their java example).  Creating a subscription request message such as:

public static Message marketDataIncrementalRequest(String symbol) {
    quickfix.fix44.MarketDataRequest tickerRequest = new quickfix.fix44.MarketDataRequest();

    quickfix.fix44.MarketDataRequest.NoRelatedSym noRelatedSym = new quickfix.fix44.MarketDataRequest.NoRelatedSym();
    noRelatedSym.set(new Symbol(symbol));
    tickerRequest.addGroup(noRelatedSym);

    tickerRequest.set(new MDReqID("123"));
    tickerRequest.set(new SubscriptionRequestType('1'));
    tickerRequest.set(new MarketDepth(0));

    addMDType(tickerRequest, '0');
    addMDType(tickerRequest, '1');
    addMDType(tickerRequest, '2');

    return tickerRequest;
}

The above message request is documented to provide full orderbook + trades snapshot + incremental refresh.  Unfortunately it just provides top-of-book with no sizes + trades with no size.   I suspect their FIX server implementation is not complete.  The same standard FIX message on OKCoin, works fine, providing full book.

The alternative API via websockets provides a call to get depth of book, however, according to documentation only provides 5 levels.

Various real-time OB viewers are showing deeper-than-5 depth, so assume there is an API for this.   Can anyone point me in the right direction?


texts: I have sent a person some bitcoin. He never sent me the goods. How can I get my funds back?

texts: I have been scammed by a person and I want to dispute a bitcoin transaction.


texts: Loosing 20 ripples for resetting ledger nano for new seed

texts: I setup my ledger nano s properly and transferred my Ripple to ledger nano. Now I want to reset my ledger nano and generate new seed. I have transferred Ripple to some other exchange to reset my ledger but last 20 ripple can't be transferred as it is required for any ripple account. Once I will reset my device, can I use the same ripple wallet so that my 20 ripples won't be lost or I will have to forget these 20 ripples in terms of resetting my ledger nano? Is there any other way to save these 20 ripples?


texts: Can you run P2Pool without having to keep the blockchain updated?

texts:
I'm guessing the answer is no, but I thought I'd ask anyway.

I'm running my miner off a USB pen at the moment and I'd like to run P2Pool but the main issue for me is there wouldn't be enough space left on the USB pen to store the blockchain.

Is there a way I can run P2Pool without having the blockchain stored locally?


texts:
I was having a look at the number of transactions in the bitcoin address for bitcoin.org.

I went to blockchain.org explorer. It says https://blockchain.info/address/1GwV7fPX97hmavc6iNrUZUogmjpLPrPFoE

No. Transactions    354

I have exported the CSV, and sorted it by "x" that is the number of each time they received some funds. The output I had is 365.

I am confused about these numbers. It is not possible that the total of funds received are higher in the CSV, than the number of Tx's.

Not sure what I am missing here.

By the way, I wanted to get people to donate more.


texts: Armory wallet and bitcoin - newbie questions

texts:
I made a transaction into my armory wallet but I didnt downloaded blockchain before. What happened to my bitcoin?
Can I access my bitcoins when ill be able to get the wallet online?


texts: How do I make a Bitcoin "memory wallet" (or paper wallet without paper)?

texts: I'd like to see a video tutorial that explains in detail how to make a paper wallet without paper, AKA, a "memory wallet" -- thx.


texts:
The bitcoin opcode seems to have a flat rate, is that correct?
Or, if bitcoin has a price per opcode, please give me the link.
If it is a flat rate, please tell me why bitcoin does not have a mechanism like ethereum.


texts:
Blockchain.info's encrypted wallet format is described as:

  AES encrypting the entire JSON payload with the users password which
  is then encoded as base64. No salt is used for single pass encryption.
  The exact AES specifications are 10 rounds of PBKDF2, Block Mode CBC
  ISO10126 padding.

However, in trying to verify my own encrypted exports, it seems thats not all the information (or correct). I think part of the issue is in how the user's password is expanded to an input key for the AES/Rijndael cipher.

The input key for AES can be 128, 192, or 256 bits; which is being used?
AES has its own key schedule, but it seems Blockchain is using something separate, as "PBKDF2" is another key expansion function.
PBKDF2 is a methodology that can be used with many types of hashes; which hash is being used?


texts: Bitcoin price drop in the past few days (25/10/12 to 27/10/12)

texts:
Does anyone have any solid ideas or knowledge on why the price has dropped so much over the past few days? There is a lot of speculation, but nothing I have read to date seems to adequately explain the recent drop.

The drop is illustrated here, and shows a decrease in price of roughly 14% over the two days:


texts:
I'm building a web app making JSON-RPC calls to the bitcoind server. I have security concerns on how to protect the wallet.dat file.

I'm encrypting the directory where wallet.dat will be.
Should I also use the bitcoind encryptwallet command?
When using Bitcoin client wallets like Electrum every time I send BTC it asks me for my password. Building a web app where users will have their own account (and addresses) should a bitcoind password be used? Does bitcoind store the private keys for every public address generated?

Thanks


texts: How would one get Bitcoin cash from their existing Bitcoin private keys?

texts: I have my bitcoin private key, how would I get bitcoin cash and where would I dump it for real bitcoin?


texts: How do I find where the BTC are sent to from a blockchain.com address page?

texts:
I could see a wallet address receiving BTC easily on a blockchain.com
But it seems very hard to find out where he/she spend the BTC.
Does anyone know how to track that?
The screenshot below: the red box is the wallet address. It's always on the receiving end.


texts: Keep getting non base-58 character error when trying to recover my old wallet. Any ideas on how to troubleshoot this?

texts: Basically I made a purchase with bitcoins back in ~2014 and I remember that I had a little bit leftover. However all documentation I have is a file labelled wallet with a huge string of characters. But when I try and access it on any application I get the non base-58 character error. There are a bunch of +'s and /'s. Does anyone have any idea what I could try to see if this is it? Sorry for not having more advance knowledge.


texts: Import newly generated address to bitcoin core

texts:
Can I import newly generated address to Bitcoin core with "importaddress" rescan false, for the watch only purpose?

why do I need to rescan if the address doesn't have any history?

Question: will it trigger the "walletnotify" if it receives new transaction on that address without rescanning.


texts: How can be proven that a signature is valid with it's public key

texts: If someone wants to make a transaction, they need to sign the transaction data with their private key. For example Sign(transactionData, privateKey) creates the signature. What is exactly this Sign function and what happens inside this function? And how can be verified that a signature is valid with a public key? For example Verify(signature, publicKey), what happens inside this function?


texts: What if I create a new address and I'm given one which clashes (already exists, it is being used by other user)

texts:
Addresses are like GUIDs, no? They are created randomly whenever you request the creation of a new address.

But what if when creating one, it clashes with one already created? I know that the probability of this is staggeringly low, but there is a probability, it is not impossible.

What would happen in this case?


texts: How to get concerned specific unspent(coin selection algorithm) from list of unspents in a wallet to calculate transaction size

texts:
I have a problem to calculate dynamic transaction fees. The problem which i am facing is to calculate the transaction size.
When i have one unspent in my wallet it is too easy to calculate transaction size. but when there are multiple unspents in wallet i think then there is some coin selection algorithm to calculate the best unspent or combination of unspents.
I have compiled document
 document  that explains this problem completely.

I need opinion in which way i wanna move? whether to develop own coin selection algorithm or there are some other options exist?


texts:
If two nodes broadcast different versions of the next block simultaneously , some nodes may receive one or the other first. In that case, they work on the first one they received but save the other branch in case it becomes longer. The tie will be broken when the next proof-of-work is found and one branch becomes longer;

I got this information from the original publication about Bitcoin. But how long is this second branch saved in memory pool of nodes? How is this conflict resolved actually? Is there any paper mentioning this?


texts: Why is the bytestring 0xaa21a9ed used as the witness commitment header in SegWit?

texts:
As per BIP 141, the witness Merkle root hash is stored in a scriptPubkey field of a coinbase transaction output with a header consisting of the 4-byte string 0xaa21a9ed. What is the reasoning behind choosing this string?

Googling only yielded a reference to namecoin on a bitcoin-dev IRC log.


texts: Maximum # of hashes for finding a block?

texts: Since nonce is a 32 bit number, the maximum value of nonce can only be 4,294,967,296. So, if a miner doesn't find the target hash within this number, what happens?


texts: how many unique bitcoins address can be generated in one address pattern

texts:
Example address prefix given below

12cgpRC5r7zakGBfRGf5RQfGCgTnp7K1Yb
12cgpFkDMJXdwck9YHrrFsWP8PgxXjtBS7
12cgpcjw2628NPAPMvzSWF9Vh2tcUJrpAa
12cgpDmDJnugoRHeAfief7KSiUFvNPF5MY
12cgpz1PwVesaKArAR53W3owQy32XKuuxT

So first 5 letters are common prefix for all address 12cgp


texts: Why is this (testnet) transaction considered invalid?


texts: Monitoring BIP125 transactions in the mempool

texts: Let's say I have a transaction with txid=A which has bip125-replaceable=True. If I bump the fee the original transaction will be removed from the mempool and replaced by the new one, so how do I know that the new transaction is, in fact, the same as the old one just with a higher fee? Does the txid stay the same? If so, than the answer is obvious. But if it changes, e.g. txid=B, then this is a completely new transaction. How can I establish the link to the old one?


texts:
it could be a basic question for you guys, but i'm new in this.

is it necessary to stay connected to internet while doing solo-mining ?

is there any method to keep mining without permanent internet connection (i mean offline mining)?

thatnk's


texts: How do I get bitcoins in the first place?

texts:
I have no bitcoins at all. But how do I get them? Can I deposit money through my credit card and convert them to bitcoin currency or something?
Also, say I have 10 BTC. Can I acquire that in physical money?


texts: Is there a flag to allow creating a transaction with multiple outputs to the same address?

texts: Does bitcoin core have a flag to allow creating a transaction with multiple outputs to the same address?


texts: What are the various block size increase proposals?

texts: I'm aware of BIP101 and BIP100, but I'm sure there are others. I would like a simple table of comparison on the block size increase schedule of each one (including the status quo) in one place.


texts: What exactly does censorship resistance mean?

texts: What features are needed for censorship resistant blockchain? In what situation can you say it's not censorship resistant?


texts:
https://blockchain.info/api/blockchain_api

multi address

I know I must be an idiot but I cannot for the life of me find out how to pass in the &limit param.

I am looking to pass in a limit of 0 because I am not interested in tx, just in balance on multiple addresses.

For example in their single address lookup:
https://blockchain.info/rawaddr/1NiNja1bUmhSoTXozBRBEtR8LeF9TGbZBN?limit=0
works exactly as expected.


texts:
I understand bitcoin is a ledger.  Everything is accounted for.  If something is debited from one side, it is credited to the other, and vice versa.
If a coin is sent to a wallet, with a public key, that doesn’t exist, the coins are considered “lost”.  But they are still debited from the wallet that sent it and credited to the wallet that doesn’t exist.
If a new wallet is created, and by mere chance, is the same address as the one the “lost” coins were sent, would those coins there when the wallet was created?
Example: coins were sent to wallet “...xyz”.  The coins were dedicated to xyz wallet, which does not exist.  I create a wallet that just happens to be xyz.  Would I have access to those bitcoin?


texts: This is a hypothetical question. Assuming that the price of bitcoin is $8,250 (as of current writing) and I had 25 billion dollars at my disposal, what would happen to the price of bitcoin if I successfully bought 100,000 bitcoins? Would I have enough money? If so, how much would it cost? I am curious about this because of the digital scarcity aspect of doing so.


texts:
Alice has 500$ and bob has 1000$. Now alice wants to transfer 100$ to bob. Miners who got the chance to validate the transaction has to check whether alice have sufficient balance or not.
where are these alice and bob balances are stored? If they are stored in the block chain, how balance is retrieved? Does entire block chain is searched to find their balance and validate and update? or block where these balances are stored is kept track any where else?

Response really helps,
Thank you.


texts:
I have incorrectly sent bitcoincash to bitcoin wallet address. (from upbit exchange in korea to kucoin exchange in hongkong)

Is there any way to get my bitcoincash back?


texts: Available ways to buy Bitcoin using leverage

texts:
I have seen several exchanges that currently offer the ability to take BTC long positions with leverage.

BTC.sx - leverage directly from the BTC.sx, 0.85% / day
Bitfinex - leverage from other account holders, rates vary, but ~ 0.15-0.20% / day over the past several days

Are there other sites?  These margin rates that I have seen are quite high.  Does anyone know of sites that offer the ability to buy BTC with leverage, but at lower rates?

I'm a "buy and hold" investor, so I am okay with committing to specific / longer timeframes to hold the BTC.  Could that help?


texts:
Does wallet notify performs actions also on old transactions? In case that my node went offline for some reason, Once its back online I will get notifications from wallet notify for the transactions that I missed when it was offline or not?

Tnx in advance!


texts: Tool to build a relational db from .dat block files

texts: No need to elaborate too much. I'd like to build a real SQL db starting from the directory blocks. Is there any tool out there? I work on a mac and I'd prefer something cross OS if possible.


texts: If I set assumevalid=0 after syncing the blockchain will Bitcoin Core go back and validate historical blocks?

texts: I originally synced my node using the Bitcoin Core default assumevalid value. If I set -assumevalid=0 in bitcoin.conf and restart my node, will my node go back and validate historical blocks?


texts: How does a client know it is connected to the right P2P network?

texts:
Global botnets of "pwned" machines exist. Hypothetically, such a botnet could be configured to look a lot like the Bitcoin peer-to-peer network.

It could even have a long (fake) block chain, full of fake timestamps showing years' worth of history where the difficulty just never got very high.

My question is simple: How does the Bitcoin client know it is connected to the "real" Bitcoin P2P network and not to an impostor? That is, what mechanisms does it use to make this identification with confidence?

The more such mechanisms you identify, the better your answer is, in my view. Thanks.


texts: How can I record block solve times on OSX?

texts:
I need to be able to record the times blocks are solved as they are solved. Bitcoin-abe would be nice (overkill, actually) but I can't get it working on my mac.

Anyone know of a mac compatible method of recording block timestamps?


texts: how do bitcoin nodes know about the full network

texts: partitions sometimes occur in a distributed network; when this happens, a node can only communicate to a subset of other nodes in the network and may use a different chain as the main chain; since current spec recommends a confirmation of 6 blocks, and current block generation speed is about 10 min / block, this means it is possible to invalidate a transaction if there is a network partition lasting longer than 1 hour; i was wondering how bitcoin client is implemented so that it know it is communicating with the full network and not suffering such network partition;


texts: In hopes of claiming BCC I sent BTC (Mycellium wallet) to a recently generated BCC wallet (Bitcoin.com). The transaction was confirmed, however, I don't see the BCC in my BCC wallet (or BTC in my BTC wallet!). How can I retrieve my BTC and BCC?


texts: I bought bitcoin a few years back before it was really in applications. My phone was destroyed and I dont really have any information to track where it was purchased from. Is there any apps or programs that help track what wallet it was purchased in, or any other ways to find out how/where this was purchased or stored.?


texts:
I generated a BTC address in "Bitcoin Core" before 2 years ago, but my HDD is burnet and I lost everything.

Unfortunately I don't saved file "wallet.dat" and I don't have "private key", but I have "passphrase".
I install diferent versins on "Bitcoin Core", but I can only add BTC address and don't can make transaction.
I added my wallet address in "blockchain.com", but to make a transaction I need a "private key"
How can I get a "private key"?


texts: Computer crashed, total reinstallation. Have wallet.dat but not private key

texts: My computer crashed and I was using the Bitcoin Core/QT client (they're the same right)? I thought I had my public and private keys saved, but those keys are from my old Armory wallet. I don't think I swept them to Bitcoin core, but I still used those keys for encryption/decryption. I was able to retrieve the wallet.dat file from the oldwindows data that is backed up on my computer, but I was wondering if I could retrieve my private key from the dat. file and how. Or if that isn't necessary, how should I go about reinstalling the bitcoin client so that I will have my coin back? I appreciate your help.


texts: Double SHA256 giving me an incorrect value with this code VB.net

texts:
I'm trying to build a bitcoin miner. I have generated the message successfully, but I can't get the double SHA256 correctly. The value I'm getting is incorrect. What is wrong with this code?

 Private Sub Button9_Click(sender As Object, e As EventArgs) Handles Button9.Click

    Dim message_combined as string = "02000000671D0E2FF45DD1E927A51219D1CA1065C93B0C4E8840290A00000000000000002CD900FC3513260DF5BD2EABFD456CD2B3D2BACE30CC078215A907C045F4992E3E5F4A5E747B1B1843F740C0"

    Dim sha256 As SHA256 = SHA256Managed.Create()
    Dim bytes As Byte() = Encoding.UTF8.GetBytes(message_combined)
    Dim hash As Byte() = sha256.ComputeHash(bytes)
    Dim stringBuilder1 As New StringBuilder()

    For i As Integer = 0 To hash.Length - 1
        stringBuilder1.Append(hash(i).ToString("X2"))
    Next

    '  Dim sha256 As SHA256 = SHA256Managed.Create()
    Dim sha256_2 As SHA256 = SHA256Managed.Create()
    Dim bytes2 As Byte() = Encoding.UTF8.GetBytes(stringBuilder1.ToString())
    Dim hash2 As Byte() = sha256_2.ComputeHash(bytes2)
    'bytes2 = Encoding.UTF8.GetBytes(bytes)
    'hash2 = sha256_2.ComputeHash(bytes2)
    Dim stringBuilder2 As New StringBuilder()

    For i As Integer = 0 To hash2.Length - 1
        stringBuilder2.Append(hash2(i).ToString("X2"))
    Next

    final_hash = stringBuilder2.ToString()

    TextBox9.Text = final_hash
End Sub

After double hashing, the end hash should be: 920F0D3EF835E723DBDA8AE0E1EA0705FAF53AC784A8116639BCB215F3BC9D8B


texts: Why are there different prices for bitcoins between exchanges?

texts:
Ive been looking around at the prices for bitcoins at various different exchanges and they all seem to have slightly (or wildly) different prices, why?

Thanks.


texts: What computational questions are solved by bitcoin miners and what is the computational complexity of one instance of this question. Essentially, how would someone program an application for bitcoin mining.


texts:
I maybe wrong but what I think is the blockchain ledger exists as long as there are active nodes in the network. So can the Bitcoin blockchain be shutdown by shutting down power supply across the globe? What would happen in such a case?

I think the transactions that were not added to the ledger would definitely be lost and they would have to be re initiated. I think power shutdown would create inconsistency between different instances of the ledger at different nodes and even if the power is back we wouldn't be able to pick a safe state of the ledger.

What are the possible ways to shutdown the blockchain without having to go to each and every node and taking it down?


texts: Where are block announce times recorded?

texts:
Times at which a block is initially announced to the network aren't recorded in the block. Does bitcoind record at least the local time each block was seen the first time? Does anyone have any suggestions about how to record these times?

I'd like to be able to use local data rather than hammer someone else's servers.


texts: After mining for a couple minutes, I stop getting shares.

texts: Can anyone explain why this would be happening? When I restart the program I quickly get shares, then after a couple minutes it almost completely stops getting shares.


texts: Litecoin mining wifi bandwidth requirements

texts:
Next week i will be mining with a total of 13Mh/s with my rigs.

What wifi bandwidth do i need to install? I've no idea how much wi-fi bandwidth is needed. I was thinking of using a 3G USB of 1GB limit/month if it is not required much bandwidth. Is it enough?

Regards,


texts: How are different Addresses generated from the same Private key?

texts:
I was reading in the "Technical background of version 1 Bitcoin addresses" that addresses are a function of the private key. More or less:

Private Key -> Public Key -> Address

If the Public Key is the only input needed to generate an Address, how come a wallet generates a different address every time? What is changing?


texts: How can I accelerate confirmations in ledger nano s?

texts:
I am using Ledger Nano S hardware wallet to store my bitcoins. Last week, for an experiment, I decided to send bitcoins to hitbtc currency exchange with zero btc fees. I was wondering how many hours will it take to transaction to be completed, but it turns out that transaction will never be completed with zero fee. I try to accelerate the procedure with ledger nano s option, but it failed many times as well. I am looking at my balance in blockchainfo, it looks like I have all the coins in my wallet, is not sent anywhere, but I cannot see the same balance in my ledger wallet. So does anyone know how can I access to my bitcoins? Thanks.

Screenshots


texts: How was FORKID used in Bitcoin Cash at the original fork point and in all upgrades since?

texts:
References:

https://github.com/bitcoincashorg/bitcoincash.org/blob/master/spec/replay-protected-sighash.md

https://github.com/bitcoincashorg/bitcoincash.org/blob/master/spec/2018-nov-upgrade.md

It looks to me like at the original fork point, Bitcoin-ABC added an extra value 0x40 called SIGHASH_FORKID that is xor'ed with the standard SIGHASH flags to produce a SIGHASH byte that is incompatible with Bitcoin Core. This provides replay protection for all transactions that are signed with ECDSA pubkeys.

Questions:

Is the FORKID updated with each "protocol upgrade" for example the recent "Magnetic Anomaly" upgrade? If not, why not?

It looks like the May 2019 upgrade will change the FORKID to 0xFF0001 but the spec mentions "Wallets that follow the upgrade should not have to change anything." -- how is that possible?

Did Bitcoin-SV change its FORKID for its recent hard fork away from Bitcoin-ABC? Is there any replay protection at all between those two chains?


texts:
I have created a altcoin using the reference of LTC and already 170k blocks were formed. Now i want to change the conformation time  as well as i want the difficulty to start from base difficulty.Basically i want to Hard fork the coin, & for that i recompiled the the code with new parameters and started the daemon.

And now i dont think the approach i took is leading me to proper direction as:

1)I am not at all able to bring the difficulty down to base difficulty.
(according my new code,difficulty shoud get adjusted after each block) &

2) some of the new node could not even get the copy of ledger even after they are connected to pre existing healthy nodes.

debug.log says:

2018-06-12 09:14:49   nActualTimespan = 0  before bounds
2018-06-12 09:14:49 GetNextWorkRequired RETARGET
2018-06-12 09:14:49 nTargetTimespan = 15    nActualTimespan = 3
2018-06-12 09:14:49 Before: 1e0ffff0  00000ffff0000000000000000000000000000000000000000000000000000000
2018-06-12 09:14:49 After:  1e033330  0000033330000000000000000000000000000000000000000000000000000000
2018-06-12 09:14:49 ERROR: AcceptBlock() : incorrect proof of work
2018-06-12 09:14:49 ERROR: ProcessBlock() : AcceptBlock FAILED

Can someone tell me is there other way by which i can Hardfork a altcoin. Or can someone suggest me what my next step could be


texts: Why "double spent" can only happen if attacker controls 51% (or more) of the network compute power?

texts: As per many descriptions block hash is calculated based on it's headers and nonce field. The latter gives a chance to get the value that is less then a target by incrementing it. If it's a lottery why is it necessary for an attacker to have more compute power then the rest of the network? Can it have a chance to get ahead of main blockchain generation if it is just lucky? I.e. nonce's it uses for own blocks generation will be always giving him desired block hash too soon? Or is it just that probability is so low that we can safely assume that this never happen?


texts: is wallet vulnerable when unlocked for transactions?.I recovered a wallet some time ago and all is good.passphrase key all looks good.But a question came to my mind about the moment we make a transaction.I guess we must be connected to the net blockchain or however  you call it.Also we unlock the wallet for the transactions right or wrong? if yes,does that not make the wallet vulnereble for hacking even for a few minuites?help appreciated.


texts:
I have 3 private keys (a,b,c) which belong to an address (2 of 3) from which I want to spend funds using RPC commands.

I´ve started with generating the redeemScript using createmultisig() and the pub keys which I have generated from the 3 priv Keys (using bitwasp). As the result returns the correct address this step seems to be correct.

After importing the address to my node and rescanning the blockchain I execute listunspend() to get the unspend outputs for my rawtransaction.

Now I generate the raw tx using

createrawtransaction({txid,vout,scriptPubKey,redeemScript},{address:amount})

Here the result:

020000000195b96fa7fff141564feba34cb669bdeb94953c98ae864465623def3fbe9e9fb10100000000ffffffff01e87a01000000000017a9145766fcbfc6927c0b027e4b4245fffcb1ec16f64b8700000000

Now I start with signing this raw transaction

signrawtransaction(rawtx,{txid,vout,scriptPubKey,redeemScript},privKey1)

The result of this signing process is used for the second step

signrawtransaction(signedrawtx,{txid,vout,scriptPubKey,redeemScript},privKey2)

The first signing step returns "Operation not valid with the current stack size" which, as far as I know is correct if a multisig address is involved and not enough keys have signed the tx.

The second step returns "Signature must be zero for failed CHECK(MULTI)SIG operation" which I don´t understand. What's going wrong here?
Even if I change the used priv keys and use the second or third key for the first signing step and one other for the second the error still persits. Am I missing a thing?


texts: How bitcoin node server establishes outbound connections to other full nodes

texts:
I installed bitcoin-core (https://bitcoin.org) on my server and run it as testnet. After that I tried to create a new testnet address "miYAFfw8xFEj2VCKKsMCu5L4uCEvC73xh5" at this page:
http://tpfaucet.appspot.com.
The problem is I don't see the address "miYAFfw8xFEj2VCKKsMCu5L4uCEvC73xh5" on my bitcoin server. I tried with RPC command:
bitcoin-cli getaddressesbyaccount "ngoc_wallet1"
But the result is empty object.

this my bitcoin.conf:

 rpcuser=bitcoinrpc
 rpcpassword=TMPP4iDWrcGMsyhZC2byTW6pb4rHcz4xK17gkKFQ4wnY

 # server=1 tells Bitcoin to accept JSON-RPC commands.
 server=1

 # Run on the test network instead of the real bitcoin network.
 testnet=1

I'm not sure what settings should I need to do more.

I would like to have synchronize bitcoin data from bitcoin network continuously. Please help me to know how the bitcoin server can accept inbound connection bitcoin data from others full node?


texts: Can we construct a UTXO which is spendable only via proof of work?

texts:
Do the current Bitcoin opcodes and transaction size limit allow constructing a UTXO which is only spendable if a specified amount of work has been performed?

So the spender, would provide a nonce as input to the script. Then the script would essentially perform a highly simplified version of how bitcoin's block headers are verified (the nonce is combined with some other data, hashed, and the hash is compared with a "target.").

Without OP_CAT and with arithmetic limited to 4 byte inputs, do I understand correctly that the above would be impossible? Or is there some workaround?


texts: Where can I find a graph of average transactions per block over time?

texts: Is there a website where I can view the size of the memory pool over time, or the average number of transactions per block?


texts: what is type of wallet with 18 words seed?

texts:
1) I have 18 words seed

  spray inject... (18 worlds total)

2) And i have some password/secret key or private key

  GVzPYhu....... (35 letters total)

What type of wallet and what crypto currency can there be access to?
I have already tried Electrum. Its dont work.
I'm ready to reward someone who will help.


texts: Why there is no block index or block height included in the block header?

texts:
Why block index or block height is not included in the block header?
Do we have to go through the whole chain if we want to know how many blocks are there in a chain?
On the other hand, if some blocks have the same hash, how to find them and get their content individually?


texts:
Think about a bitcoin transaction:

Inputs: Address1: 2 BTC, Address2: 1 BTC

Output: Address3: 3 BTC

So the value of Address1 is because of two previous transactions where every one of those 2 transactions sent 1 BTC to Address1. How is a full node now be able to verify that the amount of "2" is correct for the transaction?


texts: How are popular bitcoin wallets implemented?

texts: How are popular online bitcoin wallets, like blockchaininfo's implemented? Why aren't they open-source?


texts: What is the "sequence" and its details as referenced for the segwit application?

texts: On the segwit page there is a reference that the "feffffff" is the "sequence".  What does the "sequence" represent in relation to what?  Does it always have to be "feffffff"?  What happens if it's "feffffff" instead of "ffffffff"?  Does it help anything, does it hurt anything?  Am I just fine using just "ffffffff" instead of "feffffff" What other options are there and what do they mean?


texts: My pool shows no evidence of block that my computer discovered

texts:
It appears that my computer discovered a block i.e. bfgminer printed an Accepted line, but in my BTC Guild account there is no evidence of this and in fact, their records of when my computer last took part in the pool are wrong.
Given the hex number of my block, is there any way for me to track down the block to find out what happened to it?

UPDATE: Turns out the Accepted share was a test share, used to detect botnet machines.

Thanks.


texts: How can I find out what happened to my transaction?

texts:
I have not received a 0.1777776 BTC transaction to my Coinbase wallet that was sent from Gladiacoin on 6/3/2017. Is there anyway I can find out where this payment went?
According to Bitcoin info part of the money was transferred from my coin base address to address another bit coin address and then immediately transferred to a third account.  I did not authorize any of this so do I have any recourse to get my money back


texts: Who pays on-chain fees for settlement transaction?

texts:
Given a channel between Alice and Bob, who pays the on-chain fees when closing the channel?

Considering all possible types of closes:

Bob unilaterally closes channel
Bob wants to close the channel and Alice's node agrees (collaborative close)
Any other type of close (if there are)


texts: What is the smallest sensible transaction?

texts: While the smallest fraction of bitcoins currently implemented is the Satoshi (10-8 BTC or 10 nBTC (nano-bitcoins)), due to transaction fees there seems to be a minimum amount of BTC to be spent that is larger than one Satoshi. What is currently the smallest amount of BTC one can spend at comparably little to no fees. i.e. what is currently the smallest sensible unit of microtransactions?


texts: What is to stop people from pumping the volume of transactions via automated micropayments to a large group of addresses?

texts: This depends on the way in which # transactions are measured.


texts:
How exactly is network time sampled?

Is it as simple as one node stamping data right before being sent, the receiving node logging the current time before all other activity, and taking the difference?  Or is there something more complex involved?

Links to code would be much appreciated.


texts: How do block rewards work with a mining pool?

texts:
I understand there are a number of different schemes for sharing rewards.

My question is about the block reward itself, and how it's shared.  If only one miner (typically a pool) can find a reward, that means that a pool doesn't get a reward for every block processed.  Yet somehow, the miner is still paid, even if no block is found.

Are all the shares submitted between blocks found counted?  ie.  If a pool finds a block every 10 blocks, do the shares from the other 9 get added together and the entire block reward split across all work done on the found and previously unsuccessful blocks based on the share scheme?


texts: How to create a receiving address using the Bitcoin Core client?

texts:
Im new on bitcoin 1-2 years ago I used bitpay and coinbase but now Im trying to get the wallet directly on my macbook.Downloaded the bitcoin core from bitcoin.com

So, Im registered on https://gourl.io to use a plugin for the wordpress but in their site, a field in the form is asking me for the external wallet address.

Any one is selling digital products using edd and gourl.io ?
Can some one explain what should I do and where can I find my wallet address?

Thank you!


texts: can sender send 2 amounts to single recipient in single transaction?

texts:
I am working on web-app that needs to send money to customer's addresses.

i am trying find out if is it possible to ,
Bitcoin sender to send 2 or more amounts to single address in single transaction ?

e.g.

Transaction 1->
               sender1 -> (20 satoshis)-> receiver 1
                       -> (40 satoshis)-> receiver 1

Is this possible ?

i know i can add both amounts and do single transaction. but i would like to know can this be doable ?


texts:
I need to write a program that monitors the transactions that sent to me.
My approach is to periodically (like every 2 minutes) call the Ripple public api to get transactions for my account.  But on the developer doc, I find two way to achieve this:

Ripple Data API .
example:

  https://data.ripple.com/v2/accounts/rf1BiGeXwwQoi8Z2ueFYTEXSwuJYfV2Jpn/transactions?type=Payment&result=tesSUCCESS&limit=3

WebSocket/Json-RPC API. send to s2.ripple.com:443
with websocket or http.  example:

  {   "id": 1,   "command": "account_tx",
  "account":
  "r9cZA1mLK5R5Am25ArfXFmqgNwjZgnfk59",
  "ledger_index_min": -1,
  "ledger_index_max": -1,
  "binary": false,   "count": false,
  "limit": 10,   "forward": false }

I didn't check carefully, but they seem to have same response(with different format).

My question is :

are they equivalent?
which one should be preferred or which one is recommended by ripple?


texts: What is the difference between PSBT support in Coldcard and Trezor?

texts:
The 10x Security Bitcoin Guide says that the only two hardware wallets support BIP174 (partially signed Bitcoin transactions, or PSBT). However, this Reddit thread says that "You can use PSBT with Trezor via HWI". This Github issue elaborates.
What is the difference between the level of support of PSBT between Coldcard / Cobo and Trezor? Should a user care?


texts: How can I get logging information on incoming transactions with bitcoind?

texts: Im running two Bitcoind Nodes. Is there anyway to log the incoming transactions and the output?


texts: Possible to use an already generated bitcoin address?

texts:
Back in June I was mining just to see what it was all about.  I grabbed bitcoin-qt, generated an address and put that address into the payout info of my account at the pool I was mining in.  I told it to send to my wallet for every .5 coins mined and during the time I let it run I managed to accumulate just over .5

I eventually quit running it, and sort of forgot about it.  I later formatted and re-installed, but I remembered my progress and backed up the folder containing my miner and my wallet.  Now it's Dec and my .5 coin is worth a bit of cash.  However I didn't export or back up my wallet, I just copied the folder.  Since there was no install routine I figured this was enough to preserve my addresses.

I still have the address I told it to send to and I can see the payout in the block chain and I see my address waiting for the payment.  Is there a way to put this address into my wallet or am I out of luck?


texts: What files one should backup when running a pool or other Bitcoin service?

texts: There was a big problem with Bitomat at some point where that Bitcoin exchange lost its data due to some data being lost. To prevent such problems from occurring, what files should one backup? Which files need to be backed up only once, and which should be backed up regularly? For example, should a mining pool backup its wallet.dat often, or is once enough, as the data contained in it will never change?


texts: Easy, low fee way to move fro one paper wallet to another?

texts:
Newbie here.
I am looking for an online wallet that will support me to import Bitcoin paper wallets, then sweep each one to a new paper wallet, at the lowest fee.
I had a few accounts from three years ago and finally acted on getting my modest Bitcoin on paper wallets. After much research I chose paper, printer, method and BitCoinPaperWallet to generate the keys. A few days ago I read on Coindesk.com that there have been many reports of people losing large amounts of  Bitcoin due to a probable back door problem with BitCoinPaperwallets servers. I do not have large amounts, but still want to be cautious.
So, I want to move my several paper wallets to ones generated by BitAddress.org. I want to import the wallet to an online wallet and then sweep each one to my replacement wallet. My logic is that importing can be done without miner fees. With Bitcoin miner fees being upwards of $20 and taking 8 hours at that, at least using the import function would cut fees and time in half.
I signed up with Trust Wallet, owned by Binance and after many hours and finally submitting a question was informed that they do not support importing Bitcoin wallets. They do support importing Etherium and many others. Odd.
Can anyone recommend an online android smartphone app for me?


texts: How does using a Turing-complete programming language compromise the security of the network?

texts: I have read many places that the decision for Ethereum to use a Turing-complete programming language sparked a lot of concerns over security. From my understanding, not using a Turing-complete programming language leads to a more secure network. Why is this the case?


texts: How can I progmatically generate bitcoin address with in WASABI Deskstop wallet?

texts:
I would like to generate 10000 btc address and save it as csv file on my computer to be uploaded it on my server. I hope anyone can help me find the solution.
Thanks in advanced!


texts: Retrieving Old Transaction in Bitcoin Core's console -getrawtransactions returns "no such mempool transaction" error

texts:
I'm new to running a full bitcoin node. After almost a week I could download the entire blockchain. My computer is running 24/7 to support the cause.
When I tried to verify some old transactions that I have in the Bitcoin Core's console (version 0.20.1) I receive some error that I don't understand and my searches didn't help me resolve this issue.
I run this code in the console:
getrawtransaction transaction ID true
I paste the IDs for my past transactions
This code returns an error message saying:
No such mempool transaction. Use -txindex or provide a block hash to enable blockchain transaction queries. Use gettransaction for wallet transactions. (code -5)
It is worth mentioning that I don't use Bitcoin Core's wallet.I use a third-party wallet.
I created the bitcoin.conf file as follows (placed in ~/.bitcoin/bitcoin.conf) :
txindex=1
When I ran the bitcoin-qt I got the error message:
Error: Prune mode is incompatible with -txindex.
I was wondering if someone could help me resolve this issue?
Thanks


texts: Is it possible to append new blocks to a block of arbitrary age?

texts:
First of all, I'm aware of 51% attacks and how they work.
Though, I was wondering, if Bitcoin and other blockchains allow appending cryptographically valid, new blocks to blocks of arbitrary age (if no age restriction is in place).

For example, could I simply append a new block to the genesis block or are there any other restrictions than just the validity of the block itself?
And if this is the case, would the "Bitcoin network" really accept a completely new blockchain starting from the genesis block, if I really managed to make a blockchain with higher difficulty, than the current chain? (Like a 99,999% attack :) )


texts: How do honest mining pools generally divide their rewards?

texts: I've been reading a little about mining pools and the Stratum protocol for requesting work from mining pools and it got me to wondering.  How does an honest mining pool divide up rewards?  I see that the protocol allows for workers to request work from the pool, but how does the mining pool know how much work each worker has done?  As far as I can tell, workers only report back to the mining pool when they have "solved" a hash and want to submit their answer for consideration.  But what if that worker just lucky and there are other miners who have done  much more work -- do they get paid the same?  Similarly does a miner who is in the pool but hasn't solved anything get paid anything?


texts:
So my friend is interested in cryptocurrency and I decided to give him a hand, since he wants to start buying and selling coins for profit. I thought I could accomplish this, so I will point out my plan:

I will look into GDAX, which from what I understand will be better for us since we will be making several low price transactions.
Since GDAX can access Coinbase, I can just use my wallet from there to pull in funds.
Once I have registered on both sites, I will start creating the actual Java application.
I was thinking of using this API: https://github.com/robevansuk/gdax-java Even though it is a bit confusing for me, I think I can figure out how to do these functions: get market data (to figure out when to sell or buy), get account (obviously), deposit and withdraw from Coinbase, place a new order (for trading)

Now I wanted to ask you a few things on this plan.

1) Do you know of any examples of implementations of this API: https://github.com/robevansuk/gdax-java

2) I am using GDAX for the purpose of security and lower fees, but will withdrawing and depositing for Coinbase cost a fee?

3) I am probably a little blinded, due to my lack of knowledge in the subject. Before I get in this, could you point me into the best way of approaching this plan?


texts: My friend's dad recently started mining BTC with his gaming PC while he's not using it. As far as I can see, this kind of mining is not profitable anymore. He gets 40 Mh/s on average and apparently has made about $10 so far. I tried busting out my old Block Erupter USB miner which gets about 250 Mh/s and it hasn't made anywhere near $1. I'm wondering if he's just messing with me or if I'm missing something important. He could be mistaken about what coin he's mining but I'm pretty sure it's BTC.


texts:
This is one of those questions that everyone seems to write about but the same bad explanations are just plagiarized from site to site.

Edit: The heart of my question is why Merkle trees are claimed to be efficient when determining if a leaf node is present or tampered with when only the root node hash and a leaf node hash value is known and when the Merkle hashes are not cached somewhere (which they appear not to be in the case of Bitcoin's transactions stored in a block)... I so far see only claims of efficiency not any credible demonstrations or explanations of same. The whole point, I understand, of the Merkle "proof" is that the hashes are stored and then the binary feature of the Merkle tree can be leveraged to "walk the tree" from leaf to root with only a fraction of hash calculations required; without the cached hashes, I submit that all hashes in the entire tree would need to be recalculated, as I explain below...

I understand how to build Merkle trees. What I don't understand are two key points about Merkle trees and one key point about Bitcoin's Merkle trees for transactions. For the sake of my questions below, consider this cited Merkle tree from investopedia.com:

Merkle Trees in General

People say that given the Merkle root hash and the hash to H(D), you can quickly determine:

A. Whether the H(D) leaf is in the Merkle tree.

B. Whether the H(D) leaf has been tampered with or whether it changed positions.

With respect to A: To do this, wouldn't you just look at the list of leaf hashes to determine whether H(D) is there? Why do anything with the Merkle root?

With respect to B: If you have the H(D) hash value and you know that its leaf pair is H(C), you can calculate H(CD). But at that point, if H(D) has changed and you know the old value for H(CD), wouldn't you immediately be able to short-circuit your investigation because the new H(CD) value would not equal the old H(CD) value? If you say to me that you don't have the old H(CD) value then I would ask you: How do I get the value to H(AB) then? It would seem that I need to recalculate the hash for H(AB). And if that's true, I also would need to recalculate the hash to H(EFGH), which means recalculating the entire right half of the Merkle tree starting at the leaf nodes. There isn't much efficiency in that.

My final question:

C. Does Bitcoin persist the Merkle tree hashes for not only the leaf nodes but for the entire tree all the way to the root? Where exactly and how exactly does it store this information? All I ever see is the Merkle root in the block... I think I once saw a Merkle value for a transaction node but I never saw any meta data related to non-tree Merkle nodes in the Bitcoin blockchain...

Thanks!


texts: What sort of tasks can an ASIC be developed to do?

texts:
I know requiring a lot of memory is one thing that makes an algorithm ASIC resist. Are there any others?

Could an ASIC be developed to do Elliptic Curve Crypto? Like adding two points, or signing a piece of data? Could an ASIC be developed to solve polynomial equations?


texts: Why is my mempool count so much lower than that of block explorers?

texts:
I have been running a full node for about two days.  I wanted to get a list of all mempool txs (using getrawmempool false), and found that it only came back with around 3,000 even though all the block explorers are currently showing around 12,000.  I understand that mempools will differ between nodes, but this seems like a very big difference.  Can I do anything about this?
My getmempoolinfo:
"size": 1985,
"bytes": 3458091,
"usage": 10785216,
"maxmempool": 300000000,
"mempoolminfee": 0.00001000,
"minrelaytxfee": 0.00001000


texts: Zapped transaction, did rescan - bitcoin lost... :(

texts:
I made a transaction, realized the fee wasn't high enough, so I restarted Bitcoin-QT (MacOS) with -zapwallettxes, and removed the transaction.

Then restarted with -rescan, (been almost 24h since scan finished) but the funds are still missing. and there's no trace of the original transaction.

I don't find any trace of the transaction in the blockchain either...

Have I lost my funds? :-/

-- edit
When I import all the addresses from Bitcoin-Qt into Electrum, I can see all my funds...
Bticoin-qt still has some missing.
What am I doing wrong?


texts: BTC-Wallet from "Airgap.it" asks for Receipient-Adress-Prefix "1ABC". What format is that?

texts:
I am trying to set up a Cold and a Hot Wallet.

Hot Wallet = "Exodus" on my everyday mobile phone. Adressformat is Bech32 with Prefix "bc1" or legacy-prefix from format "P2PKH" then adresses start with "1".
Cold Wallet = "Airgap Vault" on offline Device plus "Airgap Wallet" on everyday mobile phone. Both from "airgap.it".
I tried to send a test amount from the Cold-Wallet to the Hot-Wallet, but Cold-Wallet "Airgap Wallet" only accepts BTC-Adresses starting with Prefix "1ABC". How do I obtain this adress from my "hot" Exodus-Wallet and how is this adress-standard/-format called?

I could only find BTC-Cash-related entries in Google, but BTC-Cash-Adresses start with "q" or "bitcoincash:q". Also the wallet software would have to be very misleading, because BTC-Cash is not even supposed to be supported. I can't even imagine that, so I guess I am really dumb right now. Any help is very much appreciated, thank you!


texts:
I am trying to get balance of accounts and when running bitcoin-cli listaccounts I am getting the data look like this

{
  "":0.81234545
}

I wanted to know what is the "" and 0.81234545 and where my real addresses.

Thanks!


texts:
I know that non-final transactions (locktime in future and sequence number < MAX_UINT) are not "accepted by miners". However, I could not figure out the exact behavior.

If I mined my own block with a non-final transaction, would that block be considered valid, i.e., would clients add it to their copy of the chain and would other miners build on top of that block?
(I suppose the answer is "no" because otherwise attacks on contracts could be possible.)


texts: Why a transaction couldn't be found with bitcoin-cli after 11 confirmations?

texts:
I made a new address with bitcoin-cli getnewaddress:

39WqU8NJJasFjmaS2J4424UGVJn8Tqvh82

Then I initiated a transfer from some online service.
The transaction is displayed with 11 confirmations:
https://www.blockchain.com/btc/tx/cc09117205515389ed618acd31b6e691e363446c5ce5cce94b24cc74701fbd74

Now, I am trying to verify this with bitcoin-cli:

$ bitcoin-cli listreceivedbyaddress 0 true true 39WqU8NJJasFjmaS2J4424UGVJn8Tqvh82
[
  {
    "address": "39WqU8NJJasFjmaS2J4424UGVJn8Tqvh82",
    "amount": 0.00000000,
    "confirmations": 0,
    "label": "",
    "txids": [
    ]
  }
]

$ bitcoin-cli gettransaction cc09117205515389ed618acd31b6e691e363446c5ce5cce94b24cc74701fbd74
error code: -5
error message:
Invalid or non-wallet transaction id

$ bitcoin-cli -getinfo
{
  "version": 190100,
  "protocolversion": 70015,
  "blocks": 481192,
  "timeoffset": -1,
  "connections": 10,
  "proxy": "",
  "difficulty": 923233068448.9053,
  "chain": "main",
  "walletversion": 169900,
  "balance": 0.00000000,
  "keypoololdest": 1584106964,
  "keypoolsize": 997,
  "unlocked_until": 0,
  "paytxfee": 0.00000000,
  "relayfee": 0.00001000,
  "warnings": ""
}

What should I do in order to verify locally success of the transaction?

Why balance didn't increase?

The node is configured with prune=4096.


texts: I found a GLBSE ticker that I want to invest in. The people behind it claim that it pays dividends (see http://www.blockminers.com/index.php). If I buy this stock on GLBSE, where do my dividends go? Into my GLBSE account balance?


texts: I sent a BTC to a BCH/BCC address. I have the key for the BCH/BCC account,how to retrieve?

texts:
So, I read a similar thread in which a person transferred their BTC to a BCH account and people suggested that it could be retrieved if they have the key to the BCH account.

I have the key to the BCH account since I sent it from my coinbase to my BCH wallet by mistake but in my BCH wallet i see 0 and no transaction since it was a BTC which was transferred. How can I retrieve the BTC from my BCH wallet if I have the key for the BCH wallet?


texts: btc transaction stuck from last 3 days on blockchain

texts:
I've sent a transaction on bittrex wallet, but accidentally included too little fee. What can I do to cancel the transaction or speed up the transaction's confirmation?

transaction id:

https://live.blockcypher.com/btc/tx/007f4527695f69eac30d6431f50a7b3b5befc92b99c7d8a217e0ebc37c999961/

https://live.blockcypher.com/btc/tx/9e6973cf77e7148e81c0edfca0b25a6463c80d2248c31f9b43ee0027f52d1092/


texts: How to fund a bidirectional payment channel?

texts:
Assuming two users want to create a bidirectional channel between themselves such that user_1 wants to pay 2 BTC to user_2 at the end and he divides this amount into 10 micro-payment (each micro-payment = 0.2 BTC). And user_2 wants to pay 1 BTC to user_1 at the end and he divides this amount into 10 micro-payment (each micro-payment = 0.1 BTC).

So, the capacity of this channel must be 2 BTC + 1 BTC = 3 BTC. Logically, 2 BTC of channel's capacity must be provided by user_1 and 1 BTC of channel's balance must be provided by users_2.

However, since they create together only one channel between themselves, how can they manage capacity of this channel? (I think a payment channel has a single address with a single capacity, but here since the channel is bidirectional, its capacity must be funded by two users, so how can they establish this channel together with 3 BTC ? How can they share 3 BTC between themselves ?).

If you think that question is not clear enough, please let me know.


texts: Is there a limit on the size of the block header?

texts:
I know that the current bitcoin block size limit is about 1,000,000 bytes (1 megabyte) of data. This includes both the block header as well as the transaction data.

On the other hand, the typical size of a block header is 80 bytes, or 128 bytes if padding is included (as depicted below):

Now, I have been completely unable to find any information as to whether there is a limit on the size of the block header. The block header is typically 80 bytes, but is it against protocol if a miner adds so much data that the size of the block header increases to about 192 bytes or 256 bytes?

For example, a goofy miner (for some pointless reason) adds a lot of irrelevant information after the nonce section, and the block header size increases to 256 bytes. Would this block header be considered valid?


texts:
I want to experiment in the regtest network.
But I don't understand how I can get funds to play with.
I did:

bitcoind -regtest -daemon

bitcoin-cli -regtest sendtoaddress 2N3V4PeQXoD6TFM9ZvDMX81kzbuNtc5YPW4 1

and get:

error code: -6
error message:
Insufficient funds


texts: How can I retrieve my bitcoins when the client crashes as soon as it begins synchronizing

texts: As soon as the client begins synchronizing it crashes. It's stuck at 139,500 blocks left. I am brand new to bitcoin and sent $300 to an address on this client.


texts:
I've seen several variations on "modular inverse" but I can't seem to identify the proper way of utilizing it for C++.  I'm not sure how this python code translates into c++:

def inverse(x, p):

"""
Calculate the modular inverse of x ( mod p )
the modular inverse is a number such that:
(inverse(x, p) * x) % p == 1
you could think of this as: 1/x
"""
inv1 = 1
inv2 = 0
while p != 1 and p!=0:
inv1, inv2 = inv2, inv1 - inv2 * (x / p)
x, p = p, x % p

return inv2

My current coding is here:
http://coliru.stacked-crooked.com/a/74648b16c2692525

But it only shows like the first public key properly, after that it messes up.


texts: Good informational material on BTC trading? Market vs limit?

texts: I just signed up on Gemini, and I have to admit that I have no idea what I'm doing. Is there any place I can study up on how this works?


texts: How do I prevent Bitcoin-qt from having to keep reindexing the blockchain?

texts: Is it likely that anti-malware or anti-virus software is causing this issue? (I have told such programs to exclude the Bitcoin folders from scans)


texts: How does bitcoin handle extreme transaction volume?

texts:
What would happen if the amount of active Bitcoin users grows up enough so that the average rate at which transactions are created becomes faster than the average rate at which transactions are included in the blockchain?

Even if it doesn't grow up to that point, what if someone simulates this by creating too many transactions?


texts: How can I calculate an address’s balance with “total recieved”?

texts:
I want to calculate balances of my customers with a process ,
total received(I get it via api provided by a Blockchain explorer)-total_sent(I store transactions my customers make)
 but as you know, total received amounts are different in block explorers, so I wonder if I can calculate balances correctly.

So please let me know proper solutions.


texts: bitcoinpaperwallet.com scam lost 14.5 BTC

texts:
Last night I made the mistake of using the website (while offline) to generate a wallet. I sent 0.1 then 14.5 BTC to it, and then 1 min later 14.51 was sent out to another paper wallet
here is the wallet I created and you can see the transactions
https://www.blockchain.com/btc/address/1BxPiuddFh7vz83BCFM9ZKUV75jUJyvJUv
any advice on what I can do. I've accepted the loss and the lesson (should have used the offline generator) but want to make sure this doesn't happen to others


texts: What is the meaning of the field for "Profitability decline per year" in bitcoinx' profitability calculator?

texts:
In the Bitcoin mining profitability calculator at bitcoinx.com/profit, there is a field with the description "Profitability decline per year". What does this field mean in regard to the calculation?

At a guess, I'd say, if it's set to 0.01 the projected income for a year from now will be 1% of today's projected income.


texts: How can we mine first block on bitcoin fork?

texts: We have created our altcoin and genesis block for educational purposes, but we couldn't start the mining process. Because of internal miner has been removed from bitcoin source, we can't mine. We have tried with cgminer, but because of cgminer asks getblocktemplate and gets response LEARNcoin is downloading blocks. So my question is how can we mine the first block without internal miner?


texts: Bitcoin communication with non-standard ports

texts: I'm writing a Bitcoin web app that is to be deployed on an external server over which I have no control. I probably won't have access to standard Bitcoin port (8333). Will this cause a problem when connecting to standard Bitcoin clients, or can they handle communicating with a non-standard port number? Are there any Bitcoin-related applications that also use other ports to communicate (like a pool or the like)?


texts:
I have $10 at my address. I only imported that address in my other wallet, but it shows the balance of $0 and no past transactions.
I tried my balance address of $18 and the same zero balance is shown at the imported address not even any past transaction
I even put my private key that does not show any amount
What is the problem? Can someone help with this?


texts: What can xxxCoin do to stop the impending 51% attack?

texts:
Within the coming weeks both Namecoin and SolidCoin have been threatened with the same attack. What can be done by the users, pool operators and developers of these forks to either;

A. Minimise damage.

B. Stop it altogether.


texts:
Bitcoin as a meta currency seems very useful if travelling through multiple places using currencies. I had this very intention for when I travel around asia.

What is the best method people have discovered for having the most flexible use of bitcoin when switching back to native currencies in such a manner?

Obviously, keeping fees as low as possible would be excellent.


texts:
My Copay Wallet won't open on my Android phone. When I tap on the app the Copay Logo comes up then the screen turns white.

My ohone is an android  not IOS.


texts:
I'm having trouble following LakeBTC's API instructions for connecting to their API via Python.

API Documentation:
https://www.lakebtc.com/s/api

I have my key (email address) and secret. I'm using the API URL: https://www.LakeBTC.com/api_v1

No matter what I try, I get a 401 Error. Below is my code, any ideas?

tonce = str(int(time.time() * 1e6))

p = 'tonce=' + tonce \
    + '&accesskey=' + self.key \
    + '&requestmethod=post' \
    + '&id=1' \
    + '&method=' + 'getAccountInfo' \
    + '&params='

# Create signature
hmac_obj = hmac.new(self.secret, p, hashlib.sha1)

b64 = 'Basic ' + base64.b64encode(self.key + ':' + hmac_obj.digest())

header = {
    'Json-Rpc-Tonce': tonce,
    'Authorization': b64,
    'content-type': 'application/json-rpc',
}

response = requests.post(self.apiUrl, data=p, headers=header)

Am I encrypting and hashing correctly?


texts: What are the risks of in-person private currency exchanging for travellers?

texts:
This answer suggests popularity growth of people privately exchanging bitcoins for a physical currency, in person. This might occur in "coffee shops, hotels, hostels, hackerspaces, etc".

An example would be 2 travellers meeting in a hostel in, say, the UK. Traveller A has just been to the USA and traveller B is about to go there. Traveller A has US$200 that's no longer needed, so he agrees to exchange it for some of traveller B's bitcoins.

Definitely assume traveller B has a mobile phone or other internet access to perform the transfer, but please consider both cases of traveller A having and not having similar access at the time.

What are the risks of such a deal, and what can be done to improve the chances of a successful deal?


texts:
Following the great post [Redeeming a raw transaction step by step example required, I came up with  code below but the verification failed.

// pubkeyBytes, len: 65
// 042daa93315eebbe2cb9b5c3505df4c6fb6caca8b756786098567550d4820c09db988fe9997d049d687292f815ccd6e7fb5c1b1a91137999818d17c73d0f80aef9

// data, len: 32
// 30f10a6468b7d98257af63fb40dfcf2cefe991346fd37c67cf7b51ff8d4404d3

// signatureBytes, len: 71
// 30450220587ce0cf0252e2db3a7c3c91b355aa8f3385e128227cd8727c5f7777877ad772022100edc508b7c14891ed15ab38c687019d7ebaf5c12908cf21a83e8ae57e8c47e95c

    ECPublicKey publicKey = (ECPublicKey)KeyBuilder.buildKey(KeyBuilder.TYPE_EC_FP_PUBLIC, KeyBuilder.LENGTH_EC_FP_256, false);;
    Secp256k1.setCommonCurveParameters(publicKey);
    publicKey.setW(pubkeyBytes, (short) 0, (short) pubkeyBytes.length);

    Signature eccSign = Signature.getInstance(Signature.ALG_ECDSA_SHA_256, false);
    eccSign.init(publicKey, Signature.MODE_VERIFY);
    boolean verified = eccSign.verify(data, (short)0, (short) data.length,
                signatureBytes, (short)0, (short)signatureBytes.length
            );
    Assert.assertTrue(verified);

Assertion failed at the end.

Have been stucked for hours. Cannot figure it out. Any help is highly appreciated. Thanks.


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About the content one recent user said "Wow – I went through most or all of the site, I can see you have a lot of thought into this, and a very nice informative site it is."

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