texts:
Can you break down what data is encoded into a bech32 address?
e.g. bc1qw508d6qejxtdg4y5r3zarvary0c5xw7kv8f3t4
How do bech32 addresses on testnet, regtest, signet compare?


texts:
I am trying to add already existing library below to dash source code :
Jerasure

I have included all the source and header files in a directory 'jerasure' inside 'src'.

In the Makefile.am , I have added the below lines:

libbitcoin_server_a_SOURCES = \
  jerasure/cauchy.c \
  jerasure/galois.c \
  jerasure/liberation.c \
  jerasure/reed_sol.c \
  jerasure/timing.c \
  jerasure/encoder.c \
  jerasure/decoder.c \
  jerasure/jerasure.c \
 $(BITCOIN_CORE_H)

Headers are added as below:

BITCOIN_CORE_H = \
 jerasure/cauchy.h \
 jerasure/galois.h \
 jerasure/liberation.h \
 jerasure/reed_sol.h \
 jerasure/timing.h \
 jerasure/jerasure.h

I am getting the error :

  src/Makefile.am:324: warning: variable
  'jerasure_libbitcoin_jerasure_a_SOURCES' is defined but no program or
  src/Makefile.am:324: library has 'jerasure_libbitcoin_jerasure_a' as
  canonical name (possible typo)

I have used Makefiles before, and I have been trying from sometime to get accustomed to Makefile.am idea, but not able to figure out how to get this to work.

I am able to compile this on my macOS, but not on Ubuntu 16.04 LTS.
Please help me understand what should I do in order to get this library to be used.

If there is a way to compile this as a library, that would help too.
But right now

  I want to import the Source or Header files in to already existing CPP
  files and be able to use the functionality.


texts:
Suppose the BIP32 normal deviation is not safe enough.

Suppose the xpub is deployed on the server, we assume it is public, then the leak of any derived private key is the leak of the parent private key, which means all the derived private and public key could be calculated.

Why this mode still exists, instead of using hardened mode as the default for all derive operation?

The second Point I hope to clarify here, is that if there is only one bit in the path is hardened mode, say m/0'/0/0, then the derived address is a 'hardened' address (parent private key can not be derived from parent xpub + child private key), or we need every bit in the operation is in hardened mode?

The last question is what the "layer" means exactly in BIP32?
(A) Per my understanding, if we have a master private key, any path (m/0/0, m/0'/0, m/1',m/1/2/3/) we used to derive the sub private key are the child address. If we use child address to derive again with any path (m/0/0, m/0'/1), then that is the second layer's address.
or
(B) if we have a master private key, use path (m/0') is the first layer. use path (m/0'/0) is the second layer?

What is the background and consideration for this design?


texts:
I'm new to this Bitcoin and everything seems confusing to me.

I have a requirement where I need to create wallets for every user in my application screen. So, he will transfer some Bitcoins from his personal account to the newly created account and then purchase the items present in my application.

Now, I have come across a website blockchain.info where we can create wallets by using their API.

For using that API, we need to run a local service and use the API.

My question is, if blockchain.info goes down, then do all my accounts go down?
Or, it doesn't matter if blockchain.info goes down, because the accounts are created on Main Net of Bitcoin?

Can someone, explain me this?


texts: How is “days destroyed” different from “amount of BTC” in existence?

texts:
According to https://en.bitcoin.it/wiki/Bitcoin_Days_Destroyed , if I have 100 BTC for seven days and then spend them, that’s 700 days destroyed.

But if I didn't have them, someone else would have them.  So how does the metric differ from the amount of BTC that exists?


texts: Transfering Money From My Bank Account To Bitcoin?

texts:
Im quite confused about this bitcoin software/system.

I have successfully sync'd to the network (took hours) and have recieved my address. Now, if someone is selling something for 5Bitcoins. What is the process that i have to do to remove money from my Barclays UK account and convert it bitcoins and send it to my wallet.

I really do not understand the process.

Thanks for anyone who can clear up this confusion i have.


texts:
The difficulty in Bitcoin is recalculated every 14 days. What if immediately after this difficulty adjustment someone targets Bitcoin nodes with a supercomputer and start creating new blocks?

Such attack can create some many bitcoin to complete the series to the 21 million bitcoins before the 14 days pass by. Then the difficulty will be recalculated and it is going to result sky high, because of so many blocks were generated in the previous cycle.

But after that the super computer is disconnected, and the Bitcoin network (all nodes that were mining prior the attack) will have no power to create another block. The network will stall. The interest in mining Bitcoin will disappear and nobody would be able to withdraw anything, since you would need a supercomputer to create the next block, or wait for hundreds of years for the next block to come.

Is there any error in my reasoning? Is this scenario possible?


texts: Besides the obvious privacy implications, and (according to a bitcointalk.org forum post) the fact that once an address is used your coins that rest on it safety depend entirely on the ECDSA safety (as opposed to your coins being secure if at least two of ECDSA, SHA256 and RIPEMD are secure for any address that were never used to send BTC) - are there any other reasons why it is a bad idea to reuse the same address (for sending as well as receiving BTCs) frequently?


texts: Running a Bitcoin node (behind Firewall / NAT or anything else? disallowing inbound connections)

texts:
I consider running a bitcoin full node on a raspberry Pi 3. I want to attach the raspberry Pi into my home-network (wifi). When I check my IP address I have a public address to the outside (which is changing from time to time, however is only one of 5 different addresses) and via NAT given by my ISP. I don't know what is between "my" public IP and my homenetwork in detail.

As I understand it correctly a bitcoin node does only good to the overall network iff it can accept inbound connections, therefore my raspberry pi must be publicly available (behind all this NAT whatever). If I run a bitcoin node I would like to use it at least by myself as a trusted node inside my mobile bitcoin wallet...

In the end I see two ways to do that:

Resolve NAT issues with one of the following techniques: Upnp, TURN, NAT hole punching, STUN, ICE, IGDP, NAT-PMP, PCP, ALG, wathever else there, I don't know...
Or running a hidden service.

So my question:

Is it good/bad/ok to "only" allow inbound connections as a tor hidden service?
Is there an easy way to get a bitcoin node with "traditional" means available as a public node inside a home network?


texts: (RBF) double spend transaction not showing up in searches

texts:
On my first ever attempt to send my mined bitcoins from my wallet to a bitcoin exchange site I underestimated the transaction fee that would be required to get the transaction processed. So, following online advice, I posted a RBF double spend by using Bitcoin Core's Abandon Transaction and then attempted to send a duplicate sized amount to the same address as before but with a larger transaction fee. It all looks correct on my Bitcoin Core client but the transaction ID does not show up on any site that I try (blockchain.info, tradeblock.com). The original (low fee)transaction still appears when I search for it however.

Do I just have to keep waiting or is there another issue and if so, how can I solve it?

This is the transaction id: b124aa23debcae71ca41972dbeff9327160ed092bd54a4be616b6613cfa9161b

Thanks


texts: Cryptocurrency with less deflationary properties

texts:
I wonder what is the benefit of having Bitcoin reduce the coins mined per block over time?

Suppose a slightly less deflationary growth scheme was possible (and keep other properties that make Bitcoin desirable), that might encourage more people to use it as an actual currency and less as a hoarding item.

For instance, can another blockchain-network be created that increases 0.5% the coins mined per X number of mined blocks?.


texts: Are memory pool and transaction pool the same thing?

texts: As far I know, unconfirmed transactions are stored in the memory pool. However, in the Bitcoin wiki, I see a data structure called transaction pool. Are they the same thing or not? Also for the orphan transactions, as far as I know they are stored in data structure called orphan pool, right?


texts: how can i access my private key on the BIP39, if i only got my public address?

texts: actually, i can not access my private key of my wallet after a fire incident in my house. After which i realized i cant access my private key, i have gone to the bitcoin balance checker, checked on my last transaction info, then copy the hash addresses, and try hashing on BIP39 site. i paste the hash addresses i got from the bitcoin balance checker site into the BIP39 Seed to hash out either a corresponding root key, or identifying the address from the Derived Addresses details i got on the last transaction with my wallet address, but no avail, i am so confused and frustrated, someone should please help me i have lost access to my entire fund.


texts: It sounds as if it's a process that enables a wallet to be rebuilt from a passphrase, or from several fragments scattered about. Could someone provide a detailed technical explanation?


texts: Can you mine bitcoins with an intermittent Internet connection?

texts:
I've got a very precise question and this is not a dupe of:

Does Bitcoin rely on the internet?

My question boils down to: when you mine bitcoins, how "often" does the computer/hardware doing the mining need to connect to the Internet?

However to better explain what I mean by that question, here are a few sub-questions.

When a computer is mining, when is the result of the mining accepted/confirmed?

For example, after the computer received sufficient information to start mining, when will that information not be sufficient anymore to continue mining?  In other words: when will the computer need to have Internet access so that it can continue mining? 1 picosecond? 1 nanosecond? 1 ms? 1 second? 1 minute? 1 hour? 1 day?

What happens if some computation is done on my mining computer, but then Internet connection is off? Is the result "lost" and if that result is lost, after how much time is it lost? 1 picosecond? 1 nanosecond? 1 ms? 1 minute? 1 hour? 1 day?

It may look like a "stupid" question but it would really help me better understand how BitCoin works...

(as I'm new here [but certainly not new on the SE network] I don't know which tag to use: thanks for retagging accordingly if needed)


texts:
I got bitcoin I got litecoin.

Now, where can I download namecoin client?

I don't see it here.

https://en.bitcoin.it/wiki/Namecoin

A wallet client that can do many coins at the same time would be nice


texts: What kind of a Consensus Algorithms does ripple use? Is that a leader or leaderless distributed consensus algorithm? Then what?


texts: What does the label field in Bitcoin-Qt mean?

texts:
I tried to get involved with Bitcoin on iPad, couldn't download a wallet and thought a paper wallet was an alternative; I generated said paper wallet and used the address to buy coins.

I realized I couldn't access the coins, so I bought a macbook to download a wallet. Assumed I could just add the address from the paper wallet, but its asking for a "label."


texts: Transaction not complete for two days now

texts:
I sent bitcoins to a wallet using the QR code in order to be very sure of the address. It shows in my wallet that it has been sent. But the receiver haven't seen it in his wallet. I checked it online and it shows that the money is in the address.  How can i do for him to see his coins or if not get?
I sent it to this address.
Note: the transaction shows confirmed

1N9V3yNuBEbgS3g87qibrnTGARj9SrKFst


texts: What is better, pre-existing Bitcoin-core API bindings for python or custom wrapper functions

texts:
How advisable is using the following code to query the bitcoin core as compared to using some python RPC library.

import os
btc_prefix = 'bitcoin-cli '

def getblockcount(btc_prefix):
    print("in getblockcount")
    cmd = ' '.join([btc_prefix, 'getblockcount'])
    response = os.popen(cmd).read()
    return int(response)
getblockcount(btc_prefix)

It is kind of a wrapper function for the core API's. What are the drawbacks/advantages of using the above code. Also, does it affect security in anyway.


texts:
What is the difference if I'm using bitcoins that were given me by somebody I sold product to, or by some mixing bitcoin service?

After all, aren't I using those bitcoin at the same place and ordering what I want with the same name and address?


texts:
I know about pywallet, about this modification for bitcoind, but what is a simple way to merge two wallets, or export a list of private keys and addresses of all of wallets from litecoin, dogecoin, bitcoin, quark, et cetera?

Thank you!


texts: What's the difference between the Bitcoin's peer to peer protocol and the RPC API?

texts:
Bitcoin implements both a peer-to-peer synchronization protocol (normally on port 8333) and a JSON-RPC API (normally on port 8332).

What are these designed to accomplish?
If I'm trying to implement a wallet that doesn't need bitcoind to be installed to work, which one should I use?
What existing libraries implement the low-level details of these protocols?

Related:

What is the difference between the rpc port 8332 and port 8333?


texts: The transactions-fee is set to 0.0001 btc in Multibit classic. Can I set the fee to 0.2 or 0.3 mBTC? Where is the java class that I must change to upgrade the fee? What is the var or const to change?


texts: just a simple question: what does qt in bitcoin-qt stand for?


texts:
Network: BCH testnet
Client: bitcoin-abc-0.18/bin/bitcoind and bitcoin-cli

I want to convert xPrivKey which is from exported Bitpay wallet file to private key for using bitcoin-cli importprivkey

Thank you.


texts: Bitcoin scriptSig with two transactions to unlock the scriptPubKey

texts:
For example, the bitcoin script of a scriptPubKey that consists of OP SUB < 100 > OP EQUAL, and is used to lock an output of a transaction. OP SUB pops the top two elements in the stacks, subtracts them, then pushes back the result. < X > pushes value X on the stack.
Also, the following, a scriptSig script that consists of < 200 >< 100 >, which is used as an unlocking script to spend that output.
In that case, will the scriptSig succeed to unlock the scriptPubKey thus allow the transaction to spend the money? Because of how Bitcoin combines the scripts and how it executes them, like what are the contents of the stack at each step of the execution?


texts: Why does Bitcoin Core not let met change the label for "requested payments"?

texts:
I created a receive address, entered "fdjdsgudhsgudfhgfhdgf" without thinking about it (I was going to describe it properly later) and sent coins to it from a different wallet.
Then I later changed it to "Accurate description blabla" in the "Transactions" tab, which it allowed me to do. Then I looked in the "Receive" tab and saw that it still had the stupid gibberish label there. So I went to change the label... only to realize to my horror that there is no way to change the label there, once created... ?!
Please tell me I'm hallucinating or missing something. I'll forever be annoyed by this if I'm somehow forced to keep that "fdjdsgudhsgudfhgfhdgf" label. Especially as it's now renamed in the "Transactions" tab...


texts: Are vanity addresses Vanitygen generated really safe to use?

texts:
I’m not talking about whether Vanitygen can crack an any existing wallet or not. I know it is practically impossible, considering the computational resources required.

But what if, it’s to crack vanity addresses generated by itself, Vanitygen?
If Vanitygen is deterministic and does not take any input (such as a seed) other than the desired pattern, in other words, does not walk along random steps, given the pattern input is the same, it would always require the same amount of computational resources to generate the identical first match, which is mostly affordable.
Do Vanitygen have some kind of countermeasures for this problem? Is it safe to use Vanitygen-generated wallets, free of the threat of Vanitygen-regen?


texts: Single tx included in two different blocks

texts:
https://www.blockchain.com/btc/tx/a7bacce00e5df85d3547a3f83ac10c65eec30f715c1d77d8d4a7bc17fd470965

How is it possible that a single tx is included in two different blocks?

Isn't it considered double spending?


texts:
Does the coloured coins spec (or an informal convention amongst its implementers) track coloured coins left to the miner of a transaction's block in the standard manner?

Obviously the miner would have to be running a coloured-coin-friendly mining implementation, but I was wondering if anyone knows whether there is intended to be a way for a coloured-coin-recognising miner to do this.

The coloured coin spec document at

https://github.com/killerstorm/colored-coin-tools/blob/master/colors.md

Makes no mention of mining except to say that

  Fee[s] should be paid using uncolored coins. If it is absolutely necessary to pay [a] fee with colored coins, that color should go...last.

Is it intended that in this scenario the miner can "collect" the coins while retaining their colour?


texts: Is it possible for an unsolvable block to exist?

texts:
Is there a proof that the hashing will always yield a result? Or proof that there exist unsolvable blocks?
It's my understanding that even if we hit an unsolvable block that eventually the transactions in the block would change, so what's being hashed would change. Of course, that subsequent data could also be unsolvable... etc.
I'm just curious to what we do or do not know about the solvability of blocks.


texts: How do I load money into my bitcoin account

texts: I don't understand how I load money into my bitcoin account so I can send it to someone


texts:
Say I give 1 BTC to Alice who gives it to Bob who gives it to Carol. Can I now figure out that my original BTC is now with Carol? Of course, by Carol I mean an anonymous address.

I'm thinking of a reverse wheresgeorge.com where I can trace where a BTC I owned went. I presume this is not possible otherwise hackers would never be able to keep stolen bitcoins.


texts: How can I update a transaction from Electrum?

texts:
I have not got my bitcoins confirmed in my wallet and when I try to double spend I keep getting errors mainly:
An outpoint is already spent in [DBBitcoinTx{txIndex=224965012, ip=51.254.44.148, time=1487879550, size=192, distinctIn=null, distinctOut=null, note='null', blockIndexes=[], nTxInput=1, nTxOutput=1}] [OutpointImpl{txIndex=224909177, txOutputN=3}]

any advice would be appreciated


texts: Why does Account Controls not work on the Ardor parent chain but only for child chains?

texts: Account controls that let you do account locking doesnt seem to show up on the Ardor parent chain. Why is this disabled while it works for the child chains? How does one secure their Ardor, if account control doesn't work.


texts: How to replicate getaccountaddress behaviour using getnewaddress and labels api

texts:
The problem is getaccountaddress is getting deprecated and it has specific behaviour (not related to accounts) I'm relying heavily on. It gives you the same address between multiple calls as long as there are no incoming transactions…

What I'm doing essentially is calling getaccountaddress "" every time an address needs to be displayed.

The problem is getnewaddress is designed to always provide you with a new address, so I end up flooding wallet with meaningless amount of addresses that never receive anything.

I'm trying to replicate that old behaviour using labels API, but the best I've come up with is to combine getaddressesbylabel and parsing everything listtransactions outputs to find if there's an unused receive-typed address, and to generate new one if none found.

This seems both error prone and hardly scalable, because the number of addresses will potentially grow and may become very large very fast.

What are my options? Is there an API call that can be used as a replacement for getaccountaddress "" or a combination of calls?


texts: Is there such a thing as an "ERC20 compatible Ethereum address"?

texts:
I believe the answer to be no, but just asking here to confirm.

I think the answer is that it is just the software interacting with the address that is ERC20 compatible or not, not the actual address. It doesn't matter what software generated the address, and it is fine to generate the address using any software for doing so. As long as I have the private key for the address, I can import that address into an ERC20 compatible wallet software, such as myetherwallet.com, and interact with the address in an ERC20 compatible way.

It means that the title for the e.g. the article How to generate your Ethereum ERC-20 compatible wallet address is slightly misleading, because it sounds like there is something special with the actual address generated. But how could there be, since an address is just a key pair?

Have I understood or not?


texts: How secure are the DNS servers for Bitcoin?

texts: With the version 0.6, Bitcoin introduced the DNS servers that populate the initial peers for new clients. How secure are those servers in terms of being immune to takedown attacks, or injection of malicious data?


texts: What is the Coin Base Text of a bitcoin block?

texts:
On the site https://coin.dance/blocks#blockDetails, there is a column Coin Base Text with values like Mined by AntPoolk9 Z4,b or *3Zc/BTC.COM/mm.j΀n~OoBրn*e*@ for example. What does it mean? Is it equivalent to the nonce (because I thought, the nonce is always numeric)?

And where is this information stored? In each bitcoin block? And why?


texts: What is the purpose of XBTEUR.d tradable pair?

texts:
On Kraken exchange fee page are listed tradable pairs. Some of them come with an extra suffix *.d, e.g. there are listed fees for together for XBTEUR and XBTEUR.d.

What is the purpose of these pairs? How do the fees are calculated? This information seem to be missing from the page.


texts: Does bitcoin stop periodically for finalising the next block?

texts: I have read that every once in a while, the new block is determined by a winning miner. The miner takes about 10 min to form a block out of the transactions he has received so far. Does that mean the network tells each miner all at the same time that it is the start of the race and that they are supposed to compute the next block? During this race does Bitcoin stop accepting new transactions?


texts: Can the fee be 10 times bigger than the amount that was sent?

texts: I don't understand one thing : If I get paid an amount of 0.000055 BTC ore more, how come the fee is 0.0005 ? The fee is ten times bigger than the amount I was paid?


texts: Why are the majority of miners not voting on on P2SH?

texts:
Link (via reddit)

Currently the vast majority of miners just don't vote. Was there a mistake made in organizing the voting process (maybe most miners haven't heard about this vote?), or perhaps most miners really don't like either proposals?


texts: Understanding what is being run through Sha256

texts:
When I am running through an example for Sha256 I am not understanding how to arrive at the right answer. If I use the following Hex string:

3ebb2d68d7007148b184e57bba9697d76bc04141155c57f97e3b92c5fd6a46bd

and run this through sha256, I get the following:

5f2edbb41f884a99227aedaeb5dd1739431e531d1e7be2a19976839bf9ccc17f

However, if I go the website: https://anyhash.com/sha256?hello
and run the same example through sha256, but with the Hex checkbox ticked off, I get the expected result I am looking for:

ff277f1f11cd72effe537f5e8a2690e08d8c911682d8a8150000000000000000

Can someone explain to me what it is doing when I check off that Hex checkbox? It would be helpful to know what I am transforming the Hex string into in order to run it through sha256 without having to check hex box.


texts: Does the backup (Bitcoin QT) saves my BTC if i create thousands of addresses?

texts:
I'm using the latest version of Bitcoin QT

Just encrypted it and backed it up.

If i generate 20.000 addresses, and transfer BTC to this addresses.

Would the backup i made recover all my BTC?

Thanks.


texts: why i can't find blk0001.bat and blkindex.bat on my computer

texts: my bitcoin-qt client'data is at the "C:\Documents and Settings\Administrator\Application Data\Bitcoin", but i can't find the blk0001.bat and blkindex.bat two files on this dir


texts: How can the government tax you using bitcoin

texts: Bitcoin is decentralised and anonymous so how can governments issue /enforce taxes on any transactions made with bitcoin?


texts: How could a time warp attack be prevented?

texts:
jarpian explains what a time warp attack (AKA zeitgeist attack) is:

  This is a 51% attack where the attacker sets the block timestamps artificially to lower the difficulty, allowing him to profit more coins than his hash rate would warrant. It works because the difficulty adjustment formula is based purely on timestamps that can be chosen quite freely by the attacker. In particular, the timestamps are not required to be in increasing order. ArtForz explains the attack in detail here.

  This attack was used against the new Geist Geld block chain. Geist Geld difficulty adjusts every 16 blocks making the chain particularly vulnerable against this attack. An attacker targeting Bitcoin would have to mine a full set of 2016 blocks at the current difficulty before starting to get any benefit compared to a "normal" 51% attack.

Obviously, performing this attack would be horrendously expensive. (Coinometrics places the cost at about $463 million at time of writing.)

However, if you were successful, you could lower the difficulty and increase the block rate by a factor of 4 every 2 weeks, letting you mint coins more than every 10 minutes.

The obvious way of fixing this - changing the block retarget period from (2016*n, 2016*n + 2015) to (2016*n, 2016*n + 2016) is problematic. Blocks produced by the new implementation would be invalid in the old implementation, and vice-versa. (Source)

So, how could a time warp attack be prevented in a non-disruptive way?


texts: Is there some way to estimate the proper value of one Bitcoin?

texts: For example, if it is stock, there can be P/E ratio, or Price Sales ratio. For Bitcoin, are there some common ways people use to estimate the value of one Bitcoin?


texts: blockchain.info says password is incorrect, and wont allow me to access my BTC

texts:
I had a wallet ID through blockchain.info. I signed in, received my BTC from where I bought it, all was good.

I wrote down my 12 words for recovery and have them.

I changed my password to something that I know and logged off.

When I came back, it says the password was wrong and wouldnt let me log in (YES, I'm 1000% sure my password is correct).

I used the recovery tool and the 12 phrases and got emailed a new wallet ID...my BTC are not there.

My new password does not work for my original wallet ID.

This seems to be a common problem and I would really appreciate some help.

BTC REWARD IF YOU CAN HELP ME!


texts:
As there was some disagreement on security of various models of Bitcoin clients in comments to this answer, I'd like to address the problem.

How secure are various models of Bitcoin clients? Those would include the standard client, "lightweight client" (one keeping only block headers from old blocks), eWallets, client-server client (relying on one server for all information, but keeping a wallet separate), and the proposed Stratum client (relying on many servers for information).

Also, how does the security of such model rely on the person developing it (core Bitcoin team, reputable Bitcoin enthusiasts, people not known in the community)?

For example, "Stratum client offers security features X. If the server was created by a trusted party, the security concerns are Y, if the server was created by malevolent person, the security concerns are Z".


texts: Processing bitcoins on my website completely by myself, with no third-party bitcoin SaaS services

texts:
I want to be able to accept and process bitcoins on my website only by mysefl. With no 3rd party bitcoin services. How can I do that? One way is to use Electrum. But its documentation regarding merchant is really bad. Does anyone have experience with that?
It doesn't have to be Electrum, though, and any bitcoin software will.
I'm a programmer, I'm ok implementing a neccesary part, it if I have to, by myself.


texts:
My grand father invested in a bitcoin scheme few years back he died recently.In his whatsapp he had all details about this investment. I Have no idea about how this works. I tried looking around for the site mentioned in the DMs but couldn't  find any trace of the site "https://www2.bitkingdom.org" "https://www.bitkingdom.org". I just want clarification whether my grandpa was mugged or he made it big? Any help I would really appreciate.
thank you,
jabes


texts: I bought a bunch of 2009 Bitcoins the actual coin. How can i cash the coin in?

texts: I bought several 2009 Bitcoins and they came in a nice case but that is all the info I have on them.  How do I cash them in?


texts: Why Copay sends amount from address to address?

texts: I received a payment to my Copay wallet, and in some reason Copay regularly send it from address to an other address and so forth. I can see it in https://blockchain.info What is the purpose of it? Anyway the balance is slightly falling what irritates me a bit. Why? What is the purpose behind it? Because starting application, because updating iOS?.


texts: Receive unconfirmed transactions using Insight API

texts:
I am new to Insight API. I want to receive unconfirmed transaction that are being broadcast to confirm by a miner to add in a block.

I am using Insight API using RPC client.

How I can get unconfirmed transactions similar to the ones shown on blockchain.info.


texts: Why the transactions are put into blocks in the first place

texts: I understand how transactions are grouped into blocks. However, I don't understand why this is necessary in the first place. If it's a mining thing, I don't see why the miners can't just update the transactions with some metadata and leave it at that. Then the blockchain would simply be a cache on top of the transactions. I don't see the real need for a block to exist if there are the transactions, other than it being a sort of cache.


texts: what is the relationship between the blockchain size and the transaction volume on the network?

texts:
I'm thinking about the scalability of the system with regard to the transaction volume. Is it possible to predict future blockchain size for a certain future transaction volume? Is the relationship directly proportional?

Are there any estimates compared to traditional fiat currencies transaction volumes?


texts: Are there services which I can offer to earn bitcoins?

texts:
Yes, I am a noob at this. I was wondering if anyone could let me know if I could do something sitting on the desk to earn some crypto-pie.
Also please explain how will I be able to use my bitcoins to buy other commodities - like recharge my phone and stuff.


texts: How to get private key from dogecoin wallet android app

texts:
As title, I've got an encrypted string, which gives me .org.dogecoin.production.blabla (or something like this) after I use openssl enc -d -aes-256-cbc -md md5 -a -in ENCRYPTEDFILE -out dogecoin-wallet-decrypted
After browsing, some gives me the idea to go through BIP39. Anyway, actually I don't understand it, though I did find a 12 words Mnemonic code.
So what's next ? Thanks for any help.


texts: How does the Bitcoin client encrypt the wallet.dat file?

texts: What is the algorithm used for encrypting the wallet.dat file?


texts: Since it’s not possible to know mining pools nodes addresses, how do we know the that a specific node owing 15% of share belongs to btc.com for example ?


texts: What is the Bitcoin equivalent of /dev/null?

texts: Which canonical address is a legitimate address that nobody can claim?


texts: How operations from exchange and other ways of transferring bitcoins goes into 'system' (mining people)?


texts: How to prevent ASIC mining for my new altcoin?

texts:
I want to create an altcoin that is a clone of Bitcoin. I want the mining to be ASIC resistant.
Are there any steps which I should include in my altcoin's mining algorithm to prevent ASIC mining?
Do I need to implement a completely new algorithm for mining?


texts: How can I find the "real" difficulty on testnet?

texts:
As is well known, testnet has a "20-minute rule": if no block is found within 20 minutes, the mining difficulty drops to 1 until a block is found.

From some experimentation, it appears that bitcoind's getdifficulty function reports the difficulty of the most recent block.  Thus, if the most recent block was mined under the 20-minute rule, getdifficulty returns 1.

In this case, how can I find the "real" difficulty level?  That is, the difficulty that would be required of a block submitted less than 20 minutes after the previous one?

The best approach I have found so far is to follow the blockchain back until I find a block with a difficulty other than 1 (or less than 20 minutes after the block preceding it).  But this will be prone to error if a difficulty adjustment has recently taken place.

bitcoind must know the real difficulty at all times; can I query it?


texts: Stratum Mining Proxy - Error decoding message on startup

texts:
I'm attempting to run stratum-mining-proxy with minerd. Proxy starts and runs with the following command:

python ./mining_proxy.py -o ltc-stratum.kattare.com -p 3333 -pa scrypt

Proxy starts fine. Run Minerd (U/P removed):

minerd -a scrypt -r 1 -s 6 -o http://127.0.0.1:3333 -O USERNAME.1:PASSWORD

Following errors are received. This one from the proxy:

2013-07-18 01:33:59,981 ERROR protocol protocol.dataReceived # Processing of message failed
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/stratum-0.2.12-py2.7.egg/stratum/protocol.py", line 185, in dataReceived
    self.lineReceived(line, request_counter)
  File "/usr/local/lib/python2.7/dist-packages/stratum-0.2.12-py2.7.egg/stratum/protocol.py", line 216, in lineReceived
    raise custom_exceptions.ProtocolException("Cannot decode message '%s'" % line)
'rotocolException: Cannot decode message 'POST / HTTP/1.1

And this from minerd. What am I doing wrong? Any help is appreciated!

[2013-07-18 01:33:59] HTTP request failed: Empty reply from server
[2013-07-18 01:33:59] json_rpc_call failed, retry after 30 seconds


texts: How to upgrade a Trezor device without wallet.trezor.io?

texts:
How to update a Trezor device without the Trezor backend?

The Trezor backend at wallet.trezor.io is suboptimal from a privacy perspective. Many people choose to use Electrum, Wasabi or any other wallet that offers more privacy.

The Trezor Android app may be able to upgrade a Trezor wallet this but it didn't do anything for me plus it's unclear whether it sends your XPUB to Trezor's servers anyway. So is it possible to update a Trezor hardware wallet without going to wallet.trezor.io or the Trezor Android app, and if so, how?


texts: Local Testnet3, where do the new coins get sent to?

texts:
I'm trying to setup a local testnet with multiple nodes. Currently I have three nodes, and their mining powers are almost the same.

When I use listaccounts RPC call, all the wallets have 0 coins. Even when I call listunspent 0, there are no transactions listed. How do I check how many coins I have mined so far? There have been 50 blocks in the blockchain so far.

Thanks for your help.


texts: What is the benefit of opening port 8333 to a client?

texts:
I am running a bitcoin core (v0.15.01) full node according to https://bitcoin.org/en/full-node. They say

  "To support the Bitcoin network, you also need to allow incoming
  connections."

I hesitate opening ports because having a port open for incoming connection allows for anyone to connect. So is this really necessary for bitcoin to work? They to not explicitly state what kind of support this enables.

I see that the client already makes connections to various domains like

x9.dnsseed.bluematt.me
x9.seed.bitcoinstats.com
dnsseed.bitcoin.dashjr.org
x9.seed.bitcoin.sipa.be
x9.seed.btc.petertodd.org
x9.seed.bitcoin.jonasschnelli.ch

Do these represent the "distributed" properties of Bitcoin? Why are there not more of them? Or is this completely unrelated?

Note: I have read questions like this one or this one, but they more focus on the how to, than what the benefit actually is.


texts: Can you help me tell if my new out-of-the-box ssd for a Pi4 myNode project is DOA?

texts:
Trying to setup a node on a Pi4 with ssd and blockchain appeared to be downloading well. My router said I was gobbling data for 2hrs. Then I received the "Looking for Drive" message. I rebooted once, then shut down once, then rescan which didn't seem to take and then reset . I don't think reindexing is going to do anything.

Would the upgrade from 2.0 to 2.04 help?
or
Can I get any confirmation on here it is a DOA ssd out-of-the-box?
I watched it reboot and the SSD light flashes 3x's and it did this 3x's in a row, waited a few seconds did it one more time, waited a few seconds then blinked constantly for two minutes until I shut it down.

Thank you,


texts: Bitfinex - 25% annual funding fee for margin - Fiat vs crypto - how to minimize cost?

texts:
On bitfinex, funding fee for USD is around 0.05% (daily) while that for other crypto like BTC is 5-10x smaller (around 0.008%).

In my margin account, i have positions in few crypto currencies and i have posted some USD and BTC collateral in margin account. Rest gets 'funded' with USD at 0.05% funding rate daily (thats almost 25% annual cost!).

Is it possible to fund this with BTC instead of fiat and will it reduce my daily funding cost by 5-10x. If so, what do i need to do?


texts:
I'm using c-lightning to experiment with sending micropayments backwards and forwards between 2 separate nodes.

One area I am experiencing great difficulty with is being able to generate an invoice and receiving this warning:

  "warning_capacity": "No channels have sufficient incoming capacity"

The command that received the warning above was:

$ lightning-cli invoice 1 l1 d1

The peer hash a single connection and a single channel:

$ lightning-cli listpeers
 {
  "peers": [
    {
      "id": "03eb6cac804699e4d941d4d170d088e37e67abc27b39e483fc5b68c423135cc3d4",
      "connected": true,
      "netaddr": [
        "192.168.1.11:9735"
      ],
      "global_features": "",
      "local_features": "8a",
      "globalfeatures": "",
      "localfeatures": "8a",
      "channels": [
        {
          "state": "CHANNELD_NORMAL",
          "scratch_txid": "7c621a81ed27b5e05a3e55acb5928e74f9c111bfa26f7a07660af6613e1a4453",
          "owner": "lightning_channeld",
          "short_channel_id": "1446307:37:0",
          "channel_id": "eb6227c6ff872c09b55897f49d3394dbd129b8839d05a32f6d5f93c510c3199f",
          "funding_txid": "9f19c310c5935f6d2fa3059d83b829d1db94339df49758b5092c87ffc62762eb",
          "msatoshi_to_us": 1599884,
          "msatoshi_to_us_min": 1599884,
          "msatoshi_to_us_max": 1600000,
          "msatoshi_total": 1600000,
          "dust_limit_satoshis": 546,
          "max_htlc_value_in_flight_msat": 18446744073709551615,
          "their_channel_reserve_satoshis": 546,
          "our_channel_reserve_satoshis": 546,
          "spendable_msatoshi": 1053884,
          "htlc_minimum_msat": 0,
          "their_to_self_delay": 6,
          "our_to_self_delay": 6,
          "max_accepted_htlcs": 483,
          "status": [
            "CHANNELD_NORMAL:Reconnected, and reestablished.",
            "CHANNELD_NORMAL:Funding transaction locked. Channel announced."
          ],
          "in_payments_offered": 0,
          "in_msatoshi_offered": 0,
          "in_payments_fulfilled": 0,
          "in_msatoshi_fulfilled": 0,
          "out_payments_offered": 4,
          "out_msatoshi_offered": 116,
          "out_payments_fulfilled": 4,
          "out_msatoshi_fulfilled": 116,
          "htlcs": [
          ]
        }
      ]
    }
  ]

My question is how can I determine what a channel's capacity is? I have made payments of 116 msatoshi from this node. Doesn't that mean I should now have that much incoming capacity to receive payments? Is the maximum incoming capacity of the channel msatoshi_total - msatoshi_to_us?


texts: Do we know enough about Casascius to trust their physical coins in the long run?

texts:
Casascuius offers an attractive product, a physical coin storing a private key. From a CNET article and the website itself, we learn the company is run by

  Mike Caldwell, 2901 Little Cottonwood Road, Sandy, Utah 84092,

who appears to be a trusted member of the Bitcoin community.
They provide a digitally signed list of Bitcoin addresses and claim that this makes Mike  legally accountable. (I'm not sure how the GPG key used can be connected to a real person.)

The only form of payment, they accept directly is Bitcoin.

Such a service allows for two types of fraud:

At some point in time, they stop sending physical coins in exchange for BTC received and disappear. This is a very common risk when making payments in advance and it is particularly obvious if the form of payment is designed not to allow chargebacks.
The risk here is not different from shopping at many other businesses online. However, the relatively simple website and the connection with Bitcoin, is likely to raise alarms with customers.
Although they claim otherwise, they could easily keep a copy of the private keys. This would allow spending the balance on all coins that have not been spent yet at some point in the future.

What should the Bitcoin community expect Casascius to do to render the scheme trustworthy?


texts:
I have an issue with Bitcoin Armory. I have run it on Win 7, Armory version is 0.93.3-beta. I have run it at least once a week an so far it worked properly. Now it wont sync with the network (jams at 0 %, with an error message popping up after some time). Usually this was done in half an hour or sooner. I did not change anything.

Now the solution, that I have come across was to migrate it to another computer. I have an Ubuntu home computer on which the same problem appears. I have installed Armory, but it wont start with the sync. It starts the "Initializing Torrent Engine" but stays at 0 %. So perhaps this is not an computer issue after all. Any ideas on how to get hold of my bitcoins? The Armory support did not respond. At least not yet.


texts: How to confirm that given bitcoin address is generated by given public key?

texts:
I have 10s of private and public keys associated with 10s of different addresses.

Now I have a test-net btc address "mfoxBS2TpoiUWrEV3sZopoEB6Pi2d7TE9N".

What operations can I perform to find the appropriate Public Key associated with given address?

UPDATE
I am not trying to find out reverse scenario of fetching a public key from address.

As I already have bunch of public keys. One of them have created the given address. And I just want to figure out which one is it from the whole bunch?


texts:
UPDATE ONE:

It seems I might have answered my own question.  I took an address generated on bitcoin-core 0.17.1 to a BCH ATM and it would not get accepted as a valid address.  I then took the same address to a BTC ATM and it was accepted as a valid address.

Therefore, is it safe to assume that the addresses generated by bitcoin-core 0.17.1 are not compatible with BCH?

If it is not copatible with BCH, why does it show up as a valid address on blockchain.info for both BTC and BCH?

ORIGINAL QUESTION:

I've just created a new receiving address in bitcoin core 0.17.1 and noticed that it starts with a 3.  I then posted this address into blockchain.info to make sure no one else has miraculously generated the same address.  It was a new address.

But I noticed, that the address were appearing as both a BTC and BCH address.

Does this mean I can send BTC and BCH to this address?


texts: Can more bitcoins be transferred to a paper wallet address once it is created?

texts: I created a paper wallet from coinbase with some initial amount and secured it. I want to keep adding more bitcoins to the same address. Can I do that? Are there any issues doing it?


texts: get mempool transactions of some bitcoin node?

texts:
May I connect to any bitcoin core node, for example, this node 119.23.63.114:8333 using telnet and get its mempool transactions or even broadcast some transaction?

I've read that section https://bitcoin.org/en/developer-reference#mempool but can somebody give an example?


texts: How were the secp256k1 base point coordinates decided?

texts: 79be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798,483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8 seems very random to me. I see how this point is on the curve, but how exactly was this specific point chosen to be the base point? Could other base points have worked?


texts: Determining if input is a block ID, transaction ID, or address

texts:
how do sites like https://blockexplorer.com determine if the input (see inputbox in the header of https://blockexplorer.com ) is an address, transaction ID or block ID?

I want to write something similar myself on my local machine, where I run a full node and have access to bitcoind RPC. I need to know how to direct the input given one box can be 3 things.


texts:
I am a bit new to BTC.

I bought few via Virwox and it tells me I have an address. People can send money in BTC to that address.

I also downloaded MultiBit on my Mac and I got another address.

But how do I actually own those addresses? I'd like to see some technical reference on this.

Thanks,


texts: I have read many times that bitcoin is a public blockchain. Why is that?

texts:
Is there some special reason that Satoshi made bitcoin like this. Wouldn't in a private blockchain, transfer of currency would be more secure?
Also, is it possible to create a separate blockchain to transfer bitcoin in that circle.


texts:
http://www.proofofexistence.com/about -- "Use our service to anonymously and securely store an online distributed proof of existence for any document."

  The document is certified via embedding its SHA256 digest in the bitcoin blockchain. This is done by generating a special bitcoin transaction that encodes/contains the hash via an OP_RETURN script. This is a bitcoin scripting opcode that marks the transaction output as provably unspendable and allows a small amount of data to be inserted, which in our case is the document's hash, plus a marker to identify all of our transactions.

Naïve question perhaps, but if the bitcoins are lost forever, this seems like an unfriendly use of the bitcoin protocol and the blockchain, and future versions of the protocol may prevent this type of transaction from being accepted into the blockchain?


texts: How prevalent are coin attacks with botique altcoins?

texts:
I have deployed several altcoins using various PoW algorithms on my LAN for my buddies and I to mine/learn from. We ultimately want to go the distance of deploying an altcoin to the world, writing the white paper, doing the leg work of maintaining it and getting it listed on an exchange.

I have a fear that since our incredibly slim budget has limited us to a very small amount of computational power with which to develop these altcoins (at least initially) that if/when we go the distance of releasing a fully functioning altcoin we will be swiftly crashed by someone with a cabinet full of ASICs and a love of trolling.

I guess my question(s) are how common is this and what is the least expensive but effective way of preventing it. Please don't destroy my dreams, I understand making a coin that ever ends up worth anything is highly unlikely, I am asking for technical advice relative to the issue at hand, not to be told that having a coin of value with a small development team and little capital investment is impossible.

Thanks!

Schwifty


texts: Is it possible to determine the wallet ID that received my fund from one account to another?

texts: I am new to bitcoin. I opened an account with Coinbase and also an account with Blockchain.  I transferred about $35 worth bitcoin from Coinbase to an address I generated from my Blockchain wallet. HOwever, after the transaction was completed, I was not able to locate the funds in Blockchain. I have the transaction history and even the address, but am not able to unlock it with my own wallet ids.  Blockchain support has been non-exist, so i'm writing on this blog to see anyone has similar experience and can share their thoughts on this.  I presume i will not be able to get the $35 back, but thought i give this forum a try. Thanks in advance! L


texts: Need help understanding how to profit from bitcoin trading (like forex?)

texts:
I want to understand something very basic. How does trading work between BTC & USD.

Let's say I have 1 BTC at US 100. The naive idea is "buy low" and "sell high". But I don't grasp how that work, ie, how is possible to profit in both directions.

If the value of BTC change this way (value in USD):

  110 85 102 40 70 90 115 130 100 200

What I need to do to turn a profit? And if my plan is that I don't lose more than I invest at the start?


texts: What will happen when the time field wraps around

texts:
I was rather surprised when I read about the bitcoin's block header time field is only 32 bit. Even if it is unsigned (it is) it only get us 68 more years than the Y2K38 problem. What will happen then, will we need to change the protocol? Can we? What would it imply then?

Why at first Satoshi did not put a 64 bit timestamp at first was that intended?


texts:
What is the absolute minimum amount which when transferred over a tx its value equals the tx's suggested fee? Is it the dust amount of 0.00005430 BTC? How is this value affected when that amount is the only unspent output spent in the tx and when there are more unspent outputs than just this one?

Relevant question:
What's the minimum transaction with bitcoin?


texts: How can you estimate the net amount of transactions? (deducting change)

texts: The change is usually to a different address, and it could be more or less than the amount sent to the recipient.  It seems like a crude estimate would be to just randomly remove one output (assuming num outputs >= 2), and hope it worked out on average but I was curious if anyone had better ideas.  Thanks!


texts: MultibitHD is No Longer Supported (transfer funds without fee)

texts:
I just realized that multibithd is no longer supported. I have some funds there and I try to make 2 transactions, which were not confirmed in blockchain, because I also place them without commission.

If multibithd is supposed to doesn't work. What will happen with that transaction? will it expire? will it be completed? The status in multibit is sending since December 18, 2017.

I already moved my funds to electrum and that transaction does not appear.

Also, I do not understand if the transaction is unconfirmed because it places the commission = 0  or because multibit does not work anymore.

And, what would happen if I make another transaction in electrum?

Thank you and waiting for your answers.


texts: What OP code can I use in the scripting system to make a smart contract that acts similar to a lottery

texts:
I am trying to make a smart contract that acts similar to a lottery or gambling game. Here is an example:

Alice and Bob send funds to a P2SH address. Bob is the lottery. The funds needs to be locked for some time (until the draw for example, like 5 days). For this we can use OP_CHECKLOCKTIMEVERIFY. After the nLockTime expires, if Alice guessed 3 numbers, she will get 50% of her deposit back. If she guesses 6 numbers, she will get 200% of her deposit back.

How can Bob (the lottery) commit to some numbers that Alice needs to guess before Alice funds the deposit address? Bob needs to be able to prove that the numbers were chosen before she funded the deposit address, and cannot simply deny any numbers Alice would guess.

On the other side, how can we enforce the funds go back to Alice if she guesses the numbers that were previously committed to by Bob in case Bob disappears before the draw (nLickTime expiration) time comes?

The simplest thing I can think of is Bob puts a hash of the numbers he committed to in OP_RETURN in the transaction funding the deposit address, but this is kind of a PITA and annoying and it does not offer a guarantee for Alice that she will take her money if she guesses the numbers Bob committed to even if he disappears until the draw (nLockTime expire) time comes.

Thank you.


texts: How to: Check whether or not transaction inputs have been previously spent

texts:
Maybe I have overlooked it, but I think the "Bitcoin Developer Reference" does not specify how a miner has to check whether or not transaction inputs have been previously spent.

How is it done?
And espacially how is this enforced in the process?

All I found is 5.2 "process" 2.) in the 2016 paper.

I think, the miner has to look at every block after the "oldest" referenced transaction input and make sure no transaction in no block has the appropriate transaction as input. Is that true?

In that case, what enforces the miner to do so?


texts: Can a Bitcoin miner process their own transactions for free?

texts:
Can I become a Bitcoin miner by setting up multiple nodes to give higher priority to my own transactions to process them for less fee or for no fee?

My understanding is that a confirmation is when a miner includes your transaction in a block he calculates and submits. So can you setup like six or more mining machines which gives higher priority to your own transaction if you know the transactions output addresses already? Or is it just an automatic process which you can't change?

If it's possible then how exactly I can achieve this?


texts: Building many btc adress on your website for users?

texts: Hi I am new in this financial trend. I had some experience with exchange trading and investment for Ico. I have an idea and therefore i need to create a ıco website.How can ı add on my ıco site many btc adresses for user who will get invest on my project.


texts: What's the segwit transaction serialization "flag" field for?

texts:
According to bip 141, the segwit transaction serialization format (used to compute the wtxid) is:

[nVersion][marker][flag][txins][txouts][witness][nLockTime]

The bip mentions that the flag field MUST currently be 0x01. What's the purpose of this field? Is it some kind of upgrading mechanism of the serialization format?


texts: Help - transfering bitcoin old bitcoin core 0.12.0 wallet

texts:
I have a old bitcoin core wallet 0.12.0 ... I tried to transfer bitcoin from this to a new Coinbase wallet 2 days ago... Nothing has shown up in Coinbase wallet and the status of the transation in bitcoincore shows sent - but with a ! and status 0/unconfirmed.... is this transaction ever going to work or is there a way to cancel? I dont seem to be able to do anything with it now... so am concerned about how I can I get bitcoin from this old wallet?

It also has years worth of syncing to do to catch up


texts: How to deal with the wallets with very small amount of Bitcoins?

texts:
The scenario is: You have a wallet with only 0.0001 BTC or less. The amount is less than the transaction fee. You want to transfer the coins to another wallet in order to reduce the wallet size. How can this be done?

Thank you good people:)


texts:
I want my customers to pay transaction fees. The only helpful but incomplete answer I have found so far is from here:

  You can create a transaction which spends the output to yourself, attaching a fee to that transaction. In order for miners to grab the transaction fee on that transaction, they would have to also mine the original transaction.

I have some experience of calling bitcoind methods using JSON. With these assumptions:

my account: "my"
receiver's address: "123..zyz"
coins to be sent: 0.001
transaction fee: (unpredictable)

my customer will receive 0.0008 coins if the transaction fee is 0.0002 in this case.

Am I supposed to first call method sendfrom like below?

sendfrom("my","123..zyz",0.001)

Then how do I determine the transaction fee? How do I charge the transaction fee to the receiver?
Would kind soul please provide me the detail answer with complete list of calls to Original Bitcoin client/API calls?


texts: Guidelines for creating a PHP driven web app for redeeming Bitcoin coupons

texts:
I would like to issue Bitcoin coupons with a given USD value. The redeeming web app should accept the coupon pin-code and a Bitcoin address and transfer bitcoins to that address according to the current exchange rate. I'm looking for a quick / simple solution, preferably with PHP. Looking for design guidelines and any advice to help me get started.

[edit]
To be more specific:

Is there a sample code for sending coins using bitcoind / PHP ?
Is there a 3d party API providing such functionality (instead of using bitcoind)?
Do MtGox and Tradehill have APIs for transfers?
Is captcha a must?

[end edit]


texts: Are BTC Private Keys evenly distributed in 256bit space?

texts:
If we assume that there are ~2^96 private keys for EACH bitcoin address (2^256-160) and we assume that in cryptography it is considered good property of every hash function if it evenly distributes the values in its co-domain (co-domain of the SHA256 function is the domain of the RIPEMD160).

Does that means that HALF of the ~2^96 private keys is in first 2^159 and other HALF is in 2^160 - 2^256 space?


texts:
I am designing a hardware wallet and the software that will work with it.

I plan to provide P2PKH transactions support in the software for hardware wallet to sign.

Is it mandatory to support P2SH transactions ?

In my learning and use of bitcoin I have not come across P2SH transactions.

If its mandatory how does Ledger nano/ Trezor do it?

Im a little lost with how to support P2SH transactions from UI/UX point of view too.

P2PKH are simple one-one transaction to receiver Pubkey. Any help on P2SH would be really great. Thanks in advance. Sorry if this question sounds novice, Im in learning curve.


texts:
To my understanding, miners with small computational capacity are merged within a pool with the advantage to reduce the variance of rewards.

does this miner merge all the computational power so that Pow is calculated quickly??

But it is said that the even in the mining pool , there will be only one miner who will solve the puzzle and the reward is shared by the others miners in the pool depending upon the shares solved by them . The miner leader will identify the ones which are active in solving with providing the puzzle with lower difficulty and share the reward with them.

If there is only one miner finally which solves the problem. How is this miner helped by other miner for computation? if this one miner uses only its computation power then what is different in mining solely?


texts: How Would This Procedure Be Performed? Transfer to Offline wallet

texts:
I've read alot of questions before I posted this... What I want to do is take my wallet from blockchain.info that contains a few bitcoins, and "store" it offline, however I have some specific questions if anyone can help:

I understand creating a paper wallet from blockchain.info's My Wallet. However, if I do this then won't any sensitive data still possibly be saved on their server(s), therefore rendering the paper wallet not completely secure?
In a partial answer to my first question, they have a way to generate and offline bitcoin address and corresponding private key. So would it be best to do that, and then from blockchain.info's My Wallet should I then send all bitcoins to this new bitcoin address, effectively eliminating any wallet that is saved in my account on that site? If that is the case, then:

would I even need a wallet? If my "paper wallet" shows the bitcoin address and its' corresponding private key, then is that all I need to put in a safe? just the bitcoin address that I sent all coins to from my wallet, and then that addresses private key?
should I delete any backups of the previous wallet that originally had the coins that I sent to this newly created offline address?
should I then close/delete my entire account on blockchain.info?

Forgive me if I sound redundant, but I guess I'm wondering if all I need to do is a "transaction" from my online wallet to a newly created 'offline' bitcoin address? In 10 years, in order to access these coins, I ONLY need that new bitcoin address and its private key?


texts: Can I, and how do I query the Bitcoin Core wallet to give me a list of all transactions for any specified address?

texts:
I've read some conflicting things on this.  Given any address, what would be the json command and or how would I import into python, such a query to my bitcoin core wallet for an array of all the tx id's for all tx's associated with any given address (whether part of my wallet or not)?

Or is there even a way to do that to begin with?


texts: Which is the reliability of a transaction timestamp?

texts:
Just one question. Where and how is the TIMESTAMP of a transaction generated?

Is it reliable to develop a transactions notification system?

Thank you! (I mean the time node below)

  {
  "hash":"44ffca26a089ccc806a7861e715d237d9f63b373085492f2ee82901171e8d661",
  "ver":1, "vin_sz":1, "vout_sz":2, "size":257,
  "relayed_by":"127.0.0.1", "tx_index":31066681,"result":0,
  "time":1351624745,"block_height":205754, "inputs":[ { "prev_out":{
  "type":0, "addr":"1PAPY4UN1NtFwRibWRuFT1CkgK3NvnMpoC",
  "value":879000000, "tx_index":31055718, "n":1 } } ], "out":[ {
  "addr":"1ELop4RiQtsVnqPJZHqErCvmJZPHsVn2YT",   "value":5000000,
  "type":0 } ,{ "addr":"1PAPY4UN1NtFwRibWRuFT1CkgK3NvnMpoC",
  "value":874000000,  "type":0 } ] },


texts: Why does the funder send the signed settlement to the counter-party in eltoo?

texts:
Quoting from the Eltoo paper:

Before signing and broadcasting the funding transaction the funder requires the other endpoint to create an initial settlement transaction that
returns the funds back to the funder. The initial settlement transaction
spends the funding output, and creates a single output that returns all of
the funds to the funder. This settlement transaction is then signed using
the settlement key and returned to the funder. The funder verifies that the
settlement transaction matches its expectations, i.e., it returns its funds and
is signed by the other endpoint. Now the funder can broadcast the funding
transaction, and wait for it to be confirmed effectively starting the contract.
The funder also signs the initial settlement transaction, making it complete
and returns it to the other endpoint.

In the last sentence, the funder signs the initial settlement and sends it to the other endpoint. But why does the other endpoint need it? This settlement transaction returns all funds to the funder, so there is no benefit for the counter-party to ever publish this first settlement transaction. Couldn't this step be skipped?


texts: deriveChild and signing transactions using Bit-Wasp

texts:
I'm generating multiple children using one extended key. I have no problem generating public addresses:

$master = HierarchicalKeyFactory::fromExtended(myKey);
$key = $master->deriveChild(1);
$publicAddress = $key->getPublicKey()->getAddress()->getAddress();

In order to sign a transaction, I need the public address' private key. How do I generate / extract the private key of a derived child? I'm assuming I'm not using the extended key for that.


texts:
I like the way Ripple provides effectively instantaneous transaction verification.

When building consensus how much traffic and their equivalent of orphan blocks are accumulated?

Is communication throttled at all?

Is the candidate set processed by the network or the founders?


texts:
I have a use-case where I'd only need to be monitoring the mempool transactions and recently-committed blocks/transactions (the last month's worth of blocks would be sufficient). Is there a way to tell bitcoinjs to not store the whole blockchain, but start from most current instead?

I could create my own "Storage" object for the server that doesn't write anything if the block is older than a month, but I'm pretty sure it would still try to download the whole blockchain every time it connected.

Or is there an even more lightweight bitcoin p2p node implementation that gives this sort of functionality?

(Usage Details: the use case for this is an ecommerce solution; the seller creates a new one-time use payment address (it's never been used before, so we don't care about the whole blockchain history) and tells the user to make a payment to it. Now the back end starts monitoring the bitcoin p2p network for an incoming (unconfirmed) transaction. At that point the site can tell the user the first step of ordering is complete, and move them to a "pending orders" page which long-polls for confirmations on those spends. Recent blocks would be used to track confirmations, and once confirmed, wouldn't be needed any more.)


texts: How can vulnerabilites in bitcoin be responsibly reported?

texts: I am wondering if someone discovers a bug/exploit in Bitcoin software or protocol, who should it be disclosed to? Who is the authority? What would happen if the bug went public? Has it occurred in the past?


texts: Can I rely on my full node to always have the most recent blocks?

texts:
I have a full node running and I am using ZMQ to let me know when new blocks arrive. How can I make sure that this block that my node received is a valid block written in the blockchain ledger and it is not an orphan block?
Can I rely on my full node to have the most recent blocks?


texts: When I use the getbalance command in bitcoin-cli and I set minconf to 1. Will it display the bitcoins with 1 confirmations and more? If this is true, what is a good amount of confirmations that will make the transaction safe but also fast?


texts: BIP39 Japanese Mnemonic vector unit test process

texts:
There is a json for unit tests of Japanese characters which I want to validate using Python, specifically with this fork of pybitcointools, which has bip39 functionality.

Unit tests from Trezor's python-mnemonic test vectors work fine (in Python 2.7 IME), however, this is straightforward since there's no normalization of unicode dialectics and such, since all mnemonics are lower case English.

The Japanese fields are:

Entropy (hex)
Mnemonic (Japanese)
Password (Japanese, appears to be the same for all tests)
Seed (hex, 64 bytes)
xprv

So entropy seeds mnemonic (bip39?), then mnemonic | password hashes to Seed; Seed then acts as the master key for the bip32 xprv? (correct me if I'm wrong!?)

So, assuming it's that straightforward...

how is the Japanese unicode text "normalized"? (Is it just NKFD Unicode normalization, which Electrum 2.0 does?)
what does "normal" mean for Japanese?


texts: Forks/ alternative coins and paper wallets

texts: So I have some bitcoin on paper wallets purchased at ATMs  well prior to the bitcoin cash split. I have only kept cold-storage paper thus far, but recently purchased a Ledger Nano S. My question is, with the forks of BC cash and the coming BC gold, am I missing out on these "matching funds" from the forks by not having these coins sitting in an exchange or online wallet?


texts: Is there a significance as to why bitcoin mining "costs" time/energy/money?

texts: I have heard that the bitcoin mining process was created in a way that purposefully required the expenditure of resources (energy/money) in order to add real value to bitcoins. In this way, when more miners join, the value of bitcoins would rise because there would be additional resources that would be used to process the transactions. However, the way I see it, it is the opposite. In other words, it seems that the value of a bitcoin is based on supply and demand from buyers/sellers, and the degree of mining interest is based on this pre-established value. My reasoning is that people do not suddenly decide to buy or sell bitcoin because "oh there is more mining power going into validating the blockchain so it must be worth more." On the contrary, miners enter or leave the mining process based on whether the potential reward for successfully mining a block is "worth" the work, with the value of the reward being strictly based off the current market value of a bitcoin. Would anyone like to confirm or refute the latter hypothesis?


texts: Is it legal to buy things internationally for Bitcoin from India?

texts:
I want to buy educational videos from someone in the USA, who offers them privately for sale as a digital download. He accepts Bitcoin.

I'm purchasing them from India.

Would it be legal for me to buy from him in this fashion?


texts: What is the point in using Kademlia routing if there are so few nodes?

texts: With about ~5000 full nodes, and given that this number will probably never grow too much (say, >1000000 full nodes is extremely inefficient and unlikely), then what is the point of using a Kademlia-like routing strategias? As far as I understand, for that scale just storing all nodes in all nodes is much simpler to program, and more efficient as messages can be sent in one hop from anyone to anyone.


texts: How do you calculate fees with bitcoind?

texts: Here is the transaction id as an example, please help me calculate using bitcoind: 10ff046cb00483c4b4222fe3d1798b98d5a17af55ff7fc0a6e1e2398b86c13bd


texts: Account change address is not showing up with `getaddressesbyaccount`

texts: I have a tiny question regarding the Bitcoin JSON-RPC API. I have a transaction on Testnet which sends one coin to an other address owned by me (on an other account than the sender). The sending address, mtGaEd9zZU8B7aYSuQiDFZTo2wiS8dWb3c, is listed under the default account, running getaccount mtGaEd9zZU8B7aYSuQiDFZTo2wiS8dWb3c outputs indeed an empty string. The receiving address, mzcj8xYome3gmAWZG57yutv14sctPxbPV6, is listed under an account named test, as expected running getaccount mzcj8xYome3gmAWZG57yutv14sctPxbPV6 returns test. Both addresses also show up when I use getaddressesbyaccount, but the change that went to address mnUJRd9CL3GV1QbWFxJxLj2DgE1ADSB8oR, which also returns an emtpy string when using it as argument to getaccount, doesn't show up in the getaddressesbyaccount call output. Why is that? I can't sum the balances of each addresses now for a reliable account balance, only getbalance return the right answer.


texts: Better or worse to mine multiple workers on one machine?

texts:
I use cgminer on Ubuntu 12.10 to mine bitcoins in the 50BTC pool. I have three workers set up. If I run multiple instances of cgminer, each targeted at their respective workers (1, 2, and 3), would this increase profits or just waste power?
I notice this because cgminer only uses about 80-90% of my GPU (Radeon HD 6570) anyway.


texts: What are the constraints on Bitcoin Core's wallet passphrase?

texts:
I know I can't send coin without my passphrase, but I have forgotten it. All I would like to know is, is the passphrase a phrase I come up with? Or does Bitcoin Core provide the phrase? Many thanks.
Also is it just one word or a sequence of words?


texts: generate wallets in exchanges like binance?

texts:
I'm a Laravel developer and I have a project in exchanges field. I need to know how can I generate deposit address for per coin belongs to per user.
I want to do this in secure way and I need to best suggestions.
Is HD wallets best choice for this situation? Do all coins have HD wallets?


texts: How do I export my private keys from my Bitcoin-Qt client?

texts:
Trying to use this posted method:

To export a private key from your Satoshi bitcoin-qt client:

launch your bitcoin client as usual and wait for it to load the blockchain and start up
click on 'help' in the menu bar (top right)
click on 'debug window'
select the 'console' tab
type: walletpassphrase "your walletpassphrase here" 600
type: dumpprivkey [your bitcoin address here]
this will return the private key, you can copy it now; ensure you clear your clipboard/history afterwards
type: walletlock

I do not understand what "your walletpassphrase here" means.  I do not have a wallet pass phrase to the best of my knowledge.

Also, I am a bit of an amateur at this and I still don't understand the "your public key here"..... is that the address that corresponds to your wallet? [Update: Yes, the bitcoin address.]

Trying to export the private key to another wallet because the bitcoin wallet has taken 2 days to sync and is still not done.

Any help would be very appreciated.


texts: ScriptSig field during P2PKH transaction signature

texts:
In P2PKH transactions, the content after signing the transaction contains: <signature(with hash_flag)><public_key>. However, since the signature can't sign itself, during the signature process the ScripSig field is temporarily set to a certain value.

According to the accepted answer from How to redeem a basic Tx?, the field is temporarily set with the ScriptPubKey field from the UTXO we want to redeem (in this case a P2PKH ScriptPubKey with the RIPEMD160 of the previous address). However, according to VButerin's pybitcointools, the field is set with a P2PKH ScriptPubKey with the RIPEMD160 of your own address (the one you are using as a source, and which private key will be used to sign the transaction).

I used pybitcointools signing function several times, and the generated transactions are valid, but the answer from the aforementioned question has been well received, so at this point I'm quite confused about what the field should contain.


texts: Is it possible to monitor all crypto-coins?

texts: Different coins have their own blocks and wallets, I want to build application to support multiple coins and my questions is Monitoring all coins possible(view transactions, get balance etc)?


texts: Which Bitcoin exchanges publish proof of reserves?

texts:
I am tired of fractional reserve exchanges continuing to run with account holders eventually holding the bag.

Which exchanges publish proof of reserves.

Real time proof with blockchain addresses would be best, but audited reports from a tech savvy accounting firm would be better than the status quo for most exchanges where no transparency is provided at all.


texts: how do nodes verify that a block has been solved and can be added to the blockchain

texts:
when a miner solves a block it gets sent out to the network, when other nodes receive it, how do they verify that the block received was indeed solved and can be added to the blockchain.

So you don't know what the answer is but if you got the answer you know what the question was.


texts:
Can anyone point me to the picture I saw somewhere but can not find it anymore where blockchain is represented as a line of blocks chained together. There was a locker on each little block, and each block was chained to the next one.
The blocks were forming something like a line/queue of blocks
I'm googling for an hour now and can not find it anymore

UPDATE 1

Here is a sketch of what I had in mind.
I'm sure I saw it somewhere but it might have been in a video about blockchain.

And then the block chain was like a very long (infinite) line of blocks


texts: How often do double spends happen successfully?

texts:
Judging from this list, not very often:

https://blockchain.info/double-spends

Why is this the case? I would have guessed they would have been more frequent.

Is it OK to always accept (small-to-medium) transactions as valid then?


texts: How to get unique rpcpassword for bitcoind

texts:
I am on Linux Debian 8.4 and have one server running 24/7.
I would like to help the Bitcoin network.

On https://bitcoin.org/en/full-node#other-linux-distributions I got to the point where I should run bitcoind and it should give me unique password:

  Then you can run the command bitcoind. It will print output similar to this:

But it does not print out anything. Ideas?


texts:
I installed a BCOIN full node and I would like to calculate estimated fees for Bitcoin transactions.
This functionality works perfectly in the CLI. For example:

bcoin-cli fee 3

Anyway things go wrong when I use the JS api inside my express client app:

const result = await client.estimateFee(3);

The API doesn't throw any error and no response is given back. This was copied from the official API documentation.

Please note that client and options are properly configured. It works all fine in other express routes where I use the bcoin JS API to get blockchain info, lists of transactions etc.

What's wrong? Perhaps the API changed and documentation is outdated ?

Regards


texts: Understanding a Bitcoin Double Spending Transaction by Performing one on yourself

texts:
Everyone talks about preventing a double spend transaction, but how does one do one to yourself in order to better understand the steps involved by the attacker?

What is required to do a double spend? Two phones running the same btc wallet?
Do you send at the same exact time?
Is it random a double spend happens when sending to multiple addresses?
How do certain online services that don't wait for the 1st confirmation stay in business? Wouldn't every attacker want to scam that no-confirmation service?
What are some preventive measures a business can use to prevent a double spend aside from waiting for 1-confirmation.


texts:
I am running a full node & using bitcoinABE to run a block explorer.
I have couple of wallets on 3rd party wallet providers where I can do xPub

Similar to blockchain.info xPub search how do I do it on my block explorer, or could anyone explain how xPub search works ?


texts: Are Ripple IOUs e-Money under European law?

texts:
It has been confirmed by multiple sources that Bitcoin is not electronic money according to EU Directive 2009/110/EC, mainly because it does not represent "a claim on the issuer" and does not have a "face value". Ripple IOUs however do seem to fit the definition, especially if they are denominated in government currencies. According to many national implementations of the directive, only licensed institutions are allowed to issue electronic money.

Is there any legal investigation on that matter or some expert opinion regarding whether Ripple IOUs are in fact bound by electronic money regulations in the EU?


texts: How to verify a lnurl-auth callback with python

texts:
I want to create a Python implementation of an lnurl-auth server.
I started a quick HTTP server to be the callback url, and captured the signed callback sent by BLW on Android.
?tag=login
&k1=7c27131e7fb37df50d12b0cb56ac1b76f817a5ba535b15afe43390a1f6b55d4d
&sig=30450221008172a00276a4724909b37051e98b36ba4f465aac82dd4d9609f91a3cd3be1a32022075bffd8d7697d140055b27e67d31a606435fdf5073c9c96d46a02cae06a5abc4&key=030f12794ae14407b8e1bfa1cbc297bb68ce6b24455ceab52c02da7a92782b6b14

Here is some python that attempts to verify that signature.
import secp256k1

k1 = bytes.fromhex("7c27131e7fb37df50d12b0cb56ac1b76f817a5ba535b15afe43390a1f6b55d4d")
key = bytes.fromhex('030f12794ae14407b8e1bfa1cbc297bb68ce6b24455ceab52c02da7a92782b6b14')
sig = bytes.fromhex('30450221008172a00276a4724909b37051e98b36ba4f465aac82dd4d9609f91a3cd3be1a32022075bffd8d7697d140055b27e67d31a606435fdf5073c9c96d46a02cae06a5abc4')

pubkey = secp256k1.PublicKey(key, raw=True)
sig = pubkey.ecdsa_deserialize(sig)
print(pubkey.ecdsa_verify(k1, sig))

Output: False
I don't know enough to tell what I'm doing wrong. It seems like this should be fairly standard use of the secp256k1 library.


texts: What is the required input for python-bitcoinlib getrawtransaction command?

texts:
I am running a bitcoin node on my machine, fully synced with RPC commands enabled, rpc server live and txindex=1.

In the command-line I can run the following RPC call and obtain the information about the transaction I require. I am using the cli as I need to process 2.5 million transactions.

./bitcoin-cli decoderawtransaction $(./bitcoin-cli getrawtransaction b601fc820d66b6516f89557fba9b40943df962de96b914547dec72b0f047c2f3)

Which returns a JSON output of the transaction.

However, when run with the python-bitcoinlib library it seems to give the following error message

import bitcoin, bitcoin.rpc
bitcoin.SelectParams("mainnet")
rpc = bitcoin.rpc.Proxy()
rpc.getrawtransaction("b601fc820d66b6516f89557fba9b40943df962de96b914547dec72b0f047c2f3")

  InvalidParameterError: {u'message': u'parameter 1 must be of length 64 (not 128)', u'code': -8}

What am I doing wrong, isn't b601.. the transaction id?

Edit: As per comment
I fixed it by replacing rpc=bitcoin.rpc.Proxy() with rpc=bitcoin.rpc.RawProxy(). But I would still like to know why the previous fails.


texts: What does "Unable to decode output address" mean?

texts:
On BlockChain.info, I have noticed a few transactions which send money to "Unable to decode output address".

For example, here is one:
https://blockchain.info/tx/624928439d2f668bab9f4cc1d9c4d2bc62a9603d8109d73d4fff8cf3043b68bd

All of the ones that I have seen with this message have 0 Bitcoins associated with that transfer and then some other greater than zero amount of Bitcoins sent to a valid looking address.  These weird addresses also have their money marked as "unspent".  Do they ever get marked as "spent"?

What does this message mean and why are people sending Bitcoins this way?


texts:
Is there some website that provides some webminer or other way for a person to check their mining speed without actually joining any pool or doing solo mining? Alternatively, are there some miners that can be pre-configured to perform mining on a specific pool with given credentials?

Or to put it in another way, if I wanted to simplify the process of checking a mining speed of a given computer for someone with minimal knowledge of what Bitcoin is, what websites or software should I use?


texts: I was just wondering how well this processor would do at bitcoin mining on cpuminer.


texts:
As you perhaps already know, mining started at the beginning with processors then graphic card.

I want to try to mining on a smartphone. Which electronic component will be the best to calculate hash? Processor or graphic component?

The purpose is only for testing on testnet and get the best performance.

Keywords such as mining and smartphone don't bring me any relevant results via Google.


texts: Syncing bitcoin node with multiple cores

texts:
I'm syncing my node on 32 CPUs, and it's super slow.

Obviously, syncing doesn't go in parallel. I wonder if there is any fundamental obstacle for "divide and conquer" way of doing it.

So let's say we have 62 blocks, and 2 CPUs. We divide it by half, and the first CPY syncs 1-32 blocks, and 2nd cpu syncs 33-64 blocks, after both tasks are completed, we are checking that 32 and 33 blocks match.

Am I missing something? This feature seems so simple to me but somehow not implemented.


texts: Does the `HTLC fail` routed back to sender using same path if intermediate node does not have enough capacity?

texts:
In the Lightning Network, the intermediate hop between the sender and receiver checks for possible errors(like if it has enough balance). And if there is, it sends an HTLCFail message back to the sender.

I was wondering if the HTLCFail message is sent back to the sender via the path it comes from, or it's routed by some new random path as long as it can go back and let the sender know this path cannot route?

  Payment relay (intermediate hop). H checks for possible errors (e.g., it checks whether it has enough
  balance to forward the payment). If there are errors, it sends an HTLCFail message back to S , failing
  the HTLC; otherwise, it sends an HTLCAdd message to R . (This step occurs multiple times in the general
  case of a payment going through multiple intermediate hops.)


texts: What meanings do the "NodeId", "Version" and "Services" convey on Peers tab of Bitcoin-qt Debug window?

texts:
As shown in the picture,

Is "NodeId" the ordered number (among all the existing bitcoin-core nodes) of the node that I am connected to?

How does "Version" differ from the "User Agent" version (on the picture, Version is displayed as 70015 and User Agent is displayed as "/Satoshi:0.18.0/)"?

And lastly, what does the "Service" mean (in this case displayed as "NETWORK & BLOOM & WITN...")?


texts: Why are the seeds different when going from seed to mnemonic and back using bx?

texts:
From an example in the documentation:

$ bx seed | bx mnemonic-new | bx mnemonic-to-seed | bx hd-new

655a1ed2d4fef69bb314198c7327f23c
grab special regret prepare urge evidence slush lobster midnight odor wish ketchup
57bae342ae8e69eb63f17ef993a90a59159e0f78114b602bf0ebabfec0e5d086e883c31975bf03f8a47a32853452623094d1303fd0549745db457145e5756582
xprv9s21ZrQH143K43CUCgNp5SmXzg2axQx2P4WupA2zEnKpFM19QfqfdqfpJR3yfzAXZnsHeUaQhWQMwyuqL8DbdeLeCbdMoKNn6pCY4RUn2pK

In Mastering Bitcoin, the example given here shows it going back to the seed that was originally created; this was done using an older version of bx though. Can someone explain how the seeds from line 1 and line 3 in the example are encoded/related?


texts: Is the appreciation in bitcoins taxable?

texts: If you have large gains in bitcoin, is there any way that it can be taxed?  If I have $5000, and it appreciates to $10,000 worth of bitcoin, when I sell bitcoin for dollars can it be taxed as a capital gain?  I would think that since there is no documentation to support it that it would be difficult.


texts: What ultimately happens to mining if blocks contain mostly non-Bitcoin data?

texts:
I'm trying to understand what can happen if

A block consists entirely of 3rd party (xCoin) data like Namecoin
There are no Tx fees to collect since they are on alternate chains.
Assume that the Block reward is quite low (0.25 BTC).

How will mining be profitable?

If the 3rd party data must subsidize mining, what would that subsidy look like within a block?


texts: What is the maximum number of multisigaddresses you can create?

texts:
I have created a few multisig addresses, and just tried to create a 2 of 3 address, but it returned with the 'AddCScript() failed' error.

What is the maximum number of m-sig addresses and where is this in the code? I'd like to know how to expand the limit for a test.


texts: about bitcoin market price for a shopping mall

texts:
I am thinking of making a shopping mall based on Bitcoin payment system.

But, as you all know, bitcoin market price experiences sudden rise and drop nowadays and It will also continue to fluctuate in the future.

In this situation, how should I make my shopping mall using Bitcoin ?

Existing malls using Bitcoin are accepting that ?

I have to change my product prices every time the market price of Bitcoin such as MTgox and BTC-e is changed ??

Does anyone have an idea about that?


texts: How does Bitcoin Core know that your private key relates to your public address? Are the private keys stored?

texts:
When a user creates an account on Bitcoin Core, he is assigned private keys. And he needs to use these private keys in order to send transactions onto the network.

Does Bitcoin Core store these private keys in the application or in the public ledger? Are these private keys store on a private server by Bitcoin Core developers?

When you sign a transaction with your private key, how does Bitcoin Core know that this private key is related to your public address?


texts:
I am wondering why we need Mempool (central and aggregated pool) while each miner has its own pool?
If we need the Mempool as an architectural design, how we can make sure that miners are sending their transactions to Mempool?
Is that possible for a miner to confirm a transaction on its own(Privately) but not send it to the Mempool(Shared-Public Pool?
Please correct me if my understanding from Miner pool as a private and the Mempool as a public area is not correct.
Thank you


texts: Why do leading ASICs manufacturers sell their chips?

texts:
I understand that some people have access to cheaper electricity than others. However why not just open mining facilities in the parts of the world offering the lowest cost structure? If that is not possible, then a joint miner with those miners would seem more profitable than selling the most profitable newly invented ASICs chips to the general public.

In some situations I know people will buy older ASICs miners that are no longer profitable for various reasons including a desire to help the network or speculating on future bitcoin price increases retroactively making the mining profitable. That is not my area of focus. I am more interested in why the newest most profitable ASICs chips are being sold.


texts: C secp256k1 : Segmentation Fault when passing NULL context to secp256k1_ecdsa_verify

texts:
Passing a NULL context to secp256k1_ecdsa_verify results in a segmentation fault (see attached code). I have the feeling this behavior is unintended as the secp256k1 library appears to be systematic in testing for NULL pointers. However, I am not sure because 1. you need a context to call the call back function (so can't do it here), and 2. the library does silently accept NULL context when it does not matter (so maybe it has a deliberate policy of not testing for NULL context).

#include "secp256k1.h"
#include <assert.h>

int main(){

  // valid key
  const unsigned char *pubkey_bytes = "\x03"
    "\xf0\x28\x89\x2b\xad\x7e\xd5\x7d\x2f\xb5\x7b\xf3\x30\x81\xd5\xcf"
    "\xcf\x6f\x9e\xd3\xd3\xd7\xf1\x59\xc2\xe2\xff\xf5\x79\xdc\x34\x1a";

  // valid signature
  const unsigned char *sig_bytes =
    "\x98\x62\x10\xb9\xdc\x0a\x2f\x21\xbc\xae\xc0\x96\xf4\xf5\x5f\xf4"
    "\x48\x6f\xcc\x4e\x3a\xaf\xe7\xe0\xcb\xf6\x46\x92\x59\x6e\x99\x4a"
    "\x0e\x5c\x6e\xc6\x54\x08\xd6\x5a\xae\x9e\x1c\xe8\xe9\x53\xc3\x1e"
    "\xd0\x3f\x41\x79\x09\x1d\x20\xd1\x59\xda\xe4\x19\xe9\x0c\xa3\x63";

  const unsigned char *hash_bytes =
    "\x7f\x83\xb1\x65\x7f\xf1\xfc\x53\xb9\x2d\xc1\x81\x48\xa1\xd6\x5d"
    "\xfc\x2d\x4b\x1f\xa3\xd6\x77\x28\x4a\xdd\xd2\x00\x12\x6d\x90\x69";

  int value;
  secp256k1_context *ctx;
  secp256k1_pubkey pub;
  secp256k1_ecdsa_signature sig;

  ctx = secp256k1_context_create
      ( SECP256K1_CONTEXT_VERIFY
      | SECP256K1_CONTEXT_SIGN
      );

  // parsing public key
  value = secp256k1_ec_pubkey_parse(ctx, &pub, pubkey_bytes, 33);
  assert(value == 1);

  // parsing signature
  value = secp256k1_ecdsa_signature_parse_compact(ctx, &sig, sig_bytes);
  assert(value == 1);

  // verifying signature
  value = secp256k1_ecdsa_verify(ctx, &sig, hash_bytes, &pub);
  assert(value == 1);

  // passing NULL context (SEGMENTATION FAULT)
  value = secp256k1_ecdsa_verify(NULL, &sig, hash_bytes, &pub);

  secp256k1_context_destroy(ctx);

  return 0;

}


texts:
So, I'm just starting out with bitcoin. I bought a little bit and moved it to my local wallet. Once confirmations started to arrive on that transaction, I moved a part of those bitcoins to a bitsquare wallet.

The amount was deducted ok from my first wallet, and I was able to use the amount in bitsquare for a deposit. But the status of the transmission/transaction is stuck in "sending" for two days. Since the coins i received the status has changed from "receiving" to "received" I'm thinking this one should have changed to "sent" by now. It says "seen by # peers", but nothing about confirmations.

My question then: Is this a problem? Should the status have changed to "sent" along with confirmations? Was there some process I needed to set up before sending?

(More on what I did): I am using MultiBit. After getting my coins with a few confirmations, I clicked "Send", wrote an wallet address from my bitsquare wallet, and clicked send. I read something about transaction fees and my wallet preferences is set to 0.1 mBTC (I wonder if this setting is ok).

Thank you in advance.


texts: Why does Coinbase block SatoshiDice transactions?

texts:
I noticed that Coinbase won't allow you to make transactions to SatoshiDice. Is this due to SatoshiDice being blocked in the US due to online gambling regulations, or are there additional reasons for this restriction?

What other transactions have Coinbase known to have blocked, if any?


texts:
I have compiled and build my own coin using cryptonote fork.
After that i have printed genesis block.
Then I pasted this genesis block hash and rebuild the binaries.
But, my question is:-

What to do next?

I have all this on my local pc.

How to start seed node?

I have purchased digitalocean VPS.

What files do i need to transfer to VPS.and what commands do i need to run on vps.

Please help me


texts:
I'm trying to figure out how does simple Bitcoin mining algorithm works in plain simple c or c#  or some pseudo language. I've found an example at http://pastebin.com/EXDsRbYH, but unfortunately It isn't clear what it does. I was unable to run it.

Suppose I have only one input: a Bitcoin wallet "abc..." which I would like to be used for the Bitcoins to be mined. I need simple to understand algorithm that will do the bitcoin mining on one machine with one thread on one cpu [I know it will take ages to complete :)]


texts: My Transactions hasn't been confirmed for 2days+

texts:
I am new to btc. 2 Day ago, i sent some btc and it hasn't been confirmed yet. I have learned that it s because of low fee.
1. Should I be worried about this ?
2. I googled and see that pywallet would help so I tried to use it but it didn't work . (I used electrum)
3. How can i amend my transactions using electrum? So i can add more fee.

Here are my tx
https://blockchain.info/tx/ba2d6baa3b123aee7612ae69ba72ffe2c4a3d86b12bfe5022243de6e3486b630

https://blockchain.info/tx/6267278f33a764f5a06793b8afa7996133192d07cf108243c3c5a1ae4ae3592e

Please help I am so desperate now. And this is not  dublicate post.. I have been searching here and cant find any solution yet!


texts: Is original bitcoin program needed with multibit?

texts: I have only MultiBit installed. Is this enough, or do I have to install the original bitcoin program to download the blockchain?


texts: What is the best way to create a wallet with a blank keypool then add keys to it?

texts:
The scenario is this:

User has a cold storage wallet and will import their cold storage xpub into Bitcoin Core using getdescriptorinfo and importmulti. User wants to only use the keys associated with the imported xpub as a watch-only wallet and wants to exclude all existing keys in the wallet so as to avoid getting an address not associated with their xpub when calling getnewaddress or getrawchangeaddress.

Would the best way to go about this be to create a blank wallet first with:

createwallet "Cold Storage", disable_private_keys: true, blank: true?

Or is there a simpler way to specify which addresses are generated when calling getnewaddress?


texts: What happens if a monopoly grows in Bitcoin mining and payment processing?  Here is a scenario that I have been thinking about. Some big corporation, like the Bank of Amerika, decides that Bitcoin is the future and starts to buy thousands of graphic cards. At the same time the payout for solving a block decreases and many small Bitcoin miners figure the cost of electricity and time is not worth it anymore. But the big corporation is subsidized by the present financial system and shifts profits from banking services into paying for Bitcoin processing until only it and a handful of other large banks control the majority of the Bitcoin network.  What happens then?  Do they start raising fees and requiring a credit card number to process a transaction?


texts:
What happened to this transaction?

Can someone explain it?

http://blockexplorer.com/t/9eHTFRi3Qq


texts:
I want to store the data on blockchain so that people can see and verify the data. The data format will be a simple JSON like the user details.

{'user_id': userid, 'amount': amount, 'product_id': productId, 'place_id':place'}

Is there any way to store the above data in blockchain so that people can verify their details that are not manipulated?


texts: How can I find a hash with leading zeros

texts:
I came across a similar question that was asked but the answer didn't seem quite complete.  Coding is completely foreign to me and I have spent some time trying to solve with no success.  I am trying to increase the difficulty by getting 8 leading 0s and the corresponding nonce for the initial hash (no previous blocks) in python.  Any direction here is appreciated

import hashlib

m = hashlib.sha256()
m.update(b'Your Name')
m.digest()
m.hexdigest()

'9cd26bee4d76694cb03cfee8c2355a83339157f2e9234fd1352c12597da72474'


texts: How can non-backed cryptocurrencies be stable (like by algorithm)

texts:
Is it possible that a cryptocurrency can be stable, without being backed by another currency, for example stable by algorithm?

For example, when the value is too high, the algorithm will increased the number of new tokens created, or when the value is too low, the algorithm will decrease  the number of new tokens created.

I would appreciate your help. Thanks.


texts: How to make data inside blockchain immutable

texts: I want to do simple blockchain implementation on golang, i have mongodb database with user info (Name, cardID, etc.) i want to store several information inside blockchain, and to put it inside another database BoltDB. But idk how to make this data immutable I mean how to make changes visible, for example I insert one user with (Name: Jhon, CardId: '777845') inside blockchain and after some time another guy will change this User's fileds (Name: 'Jhon', CardId: '1111'), and inside my blockchain it still will be (Name: Jhon, CardId: '777845')


texts: What can I buy with cryptocurrencies today

texts: I have read about CoinPayments, which allow stores to sell goods for crypto currencies. Are there more services like them ? Where else can I expect crypto coins to be accepted ?


texts: What is the refresh interval of MtGox ticker API?

texts: I'm using the MtGox ticker API (from MtGox API V2) and I want to know the update interval. I think it is less than 3 minutes, but is it possible to know exactly? It is important to me because I'm developing an Android app that shows the current price to the user in notification bar.


texts: How can I recover the missing end of my private key?

texts:
I found this paper among my old stuff.
What can you do with it?
Is there any way to fill in the missing part?