0
votes
1answer
9 views

What does OP_CHECKSEQUENCEVERIFY do?

Some people have suggested repurposing OP_NOP3 as a new opcode, OP_CHECKSEQUENCEVERIFY. What would the new opcode do? Why is it useful? Can't the signer choose the sequence field when they sign?
1
vote
1answer
13 views

Why does my wallet size increase over time?

Why does the size of the output of      bitcoin-clibackupwallet or, equivalently, wallet.dat increase over time?
0
votes
0answers
17 views

What would happen if I would forget my ID?

What would happen if I would forget my ID? Is that number/number and those words enough to identify my account, or I need to know also the ID? Edit: Why does that ID change? Edit: ID = ...
1
vote
0answers
13 views

bitcoin compile error on CentOS 6.6: ‘SIZE_MAX’ was not declared in this scope

I am trying to run a bitcoind instance (branch 0.10 from git repository) on CentOS 6.6 following this guide but I get this error when building LevelDB: Building LevelDB ... make[3]: Entering ...
0
votes
1answer
23 views

Recommended bitcoin wallet for beginner?

I use Windows, Android, Chrome - what wallet would be best and safest for beginner? I would like it to run on both Windows and Android. Thank you.
0
votes
0answers
8 views

P2SH that pays out only to a certain Bitcoin address?

Is it possible to create a type of redemption script that when the correct number of signatures are collected pays out to a pre-defined address ?
0
votes
0answers
8 views

Unknown key format when importing Private Key from Multibit to Blockchain.info

I'm trying to import a Private Key from MultiBit into Blockchain.info, but get an error saying "Error importing private key: Unknown Key Format". Is my MultiBit key in the wrong format or something?
0
votes
0answers
9 views

Is there a comprehensive list of altcoins protocols natively supporting Multisigs?

For cybersecurity risk reasons, I desire to stay away from trading such coins on all exchanges. Albeit, it is another matter for exchanges to support Multisig for such altcoins, and still yet another ...
4
votes
2answers
93 views

Why are transactions separate in a block?

I'm just getting started looking at bitcoin and it's protocol, so this might be an incredibly stupid question. Why does bitcoin have a separate concept of transactions? Wouldn't it be better for each ...
0
votes
0answers
6 views

Multiple transactions from a single wallet in one block [duplicate]

I am trying to understand how it would be (and if it is) possible for a single wallet address to have more than one transaction in a single block? Does a previous transaction of a wallet address need ...
0
votes
1answer
31 views

Pegged transfer from private blockchain to sidechains - Issue

I am trying to do a pegged transfer from one of my private blockchain to a sidechains using sidechain-manipulation.py ...
-2
votes
0answers
9 views

captcha not working right. i am unable to sign-up [on hold]

hi sorry my english is poor. your captcha system on sign-up form not working right. i am unable to sign-up for wallet
0
votes
0answers
15 views

listtransactions returning duplicate transactions with category “Send” & “Received” both

I am facing serious problem in listtransactions call. I am getting duplicate transactions with "send" and "Received" category. For I have sent some bitcoins from 31zeoskE8zeyQARFEVzwJzsp7GQpLn5zhF to ...
1
vote
1answer
26 views

How can a share be 'harder'

I am on a pool that asks you to select a difficulty for your miner. How can some shares be harder than others if they are just a hash?
0
votes
1answer
25 views

Cheapest way to move money from MultiBit to Coinbase

After the launch of MultiBit HD, I decided to move from MultiBit to Coinbase. What is the cheapest way to transfer all my money from one wallet to another? Can I somehow export/import my key/wallet ...
1
vote
1answer
35 views

Can you include a signature in a bitcoin payment?

I know you can use the bitcoin client to sign messages (for which you own the private key) and verify messages from other public addresses. But can you actually embed a signed message into a ...
1
vote
1answer
17 views

Would a normalized, hashed, protected chainstate reduce miner storage costs?

Spending freshly generated coins is prohibited by the protocol until there are at least 100 blocks on top of the block from which they came. This is because the chances of a 100-block reorg is ...
0
votes
0answers
18 views

What ASIC miner companies have an unflawed track record? [on hold]

I know there has been much controversey in the past with ASIC companies not delivering. Which ones left around today are still reputable?
0
votes
2answers
33 views

Can i combine 2 devices to get more power for mining

As An example lets say i have 2 USB Miners each one has 16 GH/s can i combine these 2 to mine with 32 GH/s ? And if yes pls tell me how.
1
vote
0answers
3 views

How to enable bitcoin tips between bbPress forum users on Wordpress?

I'd like to offer all the users who post to my Wordpress site's bbPress forum the ability to tip each other in bitcoin. But how? -Thanks
0
votes
1answer
8 views

Decentralized Data Storage System in NXT - How do you disable the 2 week data pruning?

Currently the NXT platform has the ability to store data in its blockchain, whereby making it a decentralized data storage system. But the thing is that the data is purged from a nodes blockchain ...
-1
votes
0answers
15 views

How can I find the spending PIN for my bitcoin app?

I purchased bitcoin through a local ATM, and when I try to complete a transaction, I am asked for a PIN. How can I recovery my spending PIN, to complete a transaction? I have a bitcoin wallet that I ...
1
vote
1answer
17 views

Breadwallet: Recovery Passphrase

Breadwallet uses a recovery passphrase in case you loose your phone. I read that you can reimport your wallet using a private key only once and after that you have to export it again in order to be ...
1
vote
0answers
209 views

Is there a payment processing system allowing the client to pay in cash/fiat money?

I am total newbie and only need an advice on the existing payment processing services available. So far I have checked only Bitpay, and noticed that on its t&c it is said that the system ...
0
votes
1answer
22 views

Which altcoins have their own mobile friendly wallet created by the core devs?

Was wondering how many coins have their core wallet software that is accessible on mobile devices? 3rd party devs do not count. Only want a list of coins that can be used on mobile devices as this ...
1
vote
1answer
42 views

Is there a (potential) “Blockchain size problem”, and what solutions are available?

As more and more Bitcoin transactions are produced, the growth of the Blockchain may well, one day, become a problem for systems which want (need?) to store the whole blockchain. Storage usage ...
-2
votes
0answers
13 views

Framework for Valuing Volunteering Activities - Crypto Value for Volunteer Work & Community Tasks [on hold]

Framework for Valuing Volunteering Activities - Crypto Value for Volunteer Work & Community Tasks The purpose is to provide a vehicle and framework for '''Co-operative framework''' for groups ...
-1
votes
0answers
11 views

Which exchange is the most secure? [on hold]

I'm new to bitcoin, which exchange woudl you recommend to use that is least likely to get me into trouble?
0
votes
2answers
20 views

Do Multi-Signature Wallets Require Two Separate Bitcoin Wallets?

Put more simply, is it possible to set up a multi-signature wallet that takes both signatures from itself?
0
votes
1answer
23 views

How to buy bitcoin online and then store it on my desktop wallet?

Based on popular recommendations, I have started with Electrum as my Ubuntu desktop wallet and Coinbase as the way to buy bitcoin online. However, it doesn't seem like there is an easy way to ...
0
votes
0answers
14 views

How to send an invalid transaction for testing purposes?

How could I send an invalid transaction—for testing purposes, such as with testnet or regtest? For example, I would like to to try to double-spend, spend non existent coins, etc.
1
vote
0answers
21 views

Is Bitcoin vulnerable to a Birthday Attack against Private Keys? [duplicate]

This is a definition of the Birthday Attack. Someone claims Bitcoin is vulnerable to such an attack in the bitcoin IRC chat. Are they correct?
2
votes
1answer
13 views

Restore Seed with Password

I am running Electrum 2.3.2. I had 2-factor authentication enabled with Google Authenticator, but then got a new phone. I know the password to the wallet but do not have the 2-factor code anymore. I ...
2
votes
2answers
26 views

How does Nxt agree on a chain when “active accounts” can be easily faked?

From what I understand, in Nxt, blocks are mined (or forged) using a system based on Proof-of-Stake where block creation works similarly to a lottery: people have tickets, and the more tickets you ...
2
votes
2answers
14 views

What happens to unclaimed Open Assets (colored coins) asset quantity units?

I'm trying to understand the Open Assets transaction example given here. Everything makes sense, more or less, until the end of the description: Output 6 receives the first 3 units of input 5. ...
0
votes
0answers
12 views

Relationship between concentration of bitcoin wealth and foreign exchange value?

Is there a relationship between the equality of wealth of bitcoin holders, and it's foreign exchange value? E.g. if there is a large transfer of bitcoin to a single owner, should this influence its ...
0
votes
0answers
15 views

New to Bitcoin and Blockchain - Want to meet? [on hold]

I'm absolutely new to blockchain technology and bitcoin (I know this statement creates emotional bias like "another rookie have found stack exchange" or "eternal september biases", and I appreciate ...
1
vote
2answers
102 views

Sending funds on same block of received funds. Confirm sending not received?

My question in quite conceptual: For creating a raw transaction, I just need the txid from the older transaction and the address to send it. Put the funds, the change, what's left is the fee. Sign it ...
0
votes
1answer
23 views

How to get pending balance in with bitcoinj?

I'm try get pending balance from wallet, but results do not match with pending transactions? Thanks for advice!
1
vote
1answer
54 views

Bitcoin how to get X value from Y

How to get X value from Y? ECDSA x,y coordinate validity verification doesn't seem to work X = 0x79be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798 Python code, p = ...
0
votes
0answers
26 views

Antminer U3 Low Worker Hash

Running on a raspberry pi, wifi dongle. Everything is set up, and in the pi terminal it shows 60 ghs+. However, on my pool monitor, it shows barely over 30 ghs. It was at like 20 when I started 5 ...
0
votes
3answers
9 views

getnewaddress and watch-only addresses (importaddress)

I am aware it is possible to use "importaddress" to import bitcoin addresses without their associated private keys. For an online shop that uses "getnewaddress" in order to present a customer with an ...
0
votes
1answer
21 views

How to apply blockchaining to data?

I would like to apply blockchaining on unstructured data (any kind of data). I have seen BlockSign use similar concept to sign a document by storing a hash of the document in OP_RETURN block of ...
0
votes
1answer
15 views

Is it possible to execute a CLTV transaction in bitoin core 0.11 console?

The title says it all. How can one perform a op_checklocktimeverify transaction using bitcoin core? I've searched around and I've found a few repo's on github but nothing about how to do it in the ...
-1
votes
0answers
40 views

Is it legal to pay for Bitcoin with mailed cash? [on hold]

Is it legal to offer a Bitcoin to cash service/use one? I mean Bitcoin to cash service as in sending cash by mail in return for Bitcoin. If not, what laws are being broken? Why is there only a shady ...
3
votes
1answer
45 views

How is the next forger decided in Nxt?

I've read both the Nxt whitepaper and many other resources on the wiki but I still can't seem to understand how exactly the forging process works. From what I understand, there are a bunch of online ...
0
votes
1answer
14 views

jsonRPCClient.php not working

I got bitcoind working in the cmd prompt; Then I closed it and opened bitcoin-qt and that is now running in server mode; (bitcoinf server=1) Then I run some simple .php on my localhost (using xampp ...
0
votes
0answers
17 views

Bitcoin soft fork hypothetical issue based off BIP66

Recently I saw BIP66 activation occur on testnet, but then the majority of miners were propogating V2 blocks again, causing 0.10 nodes to reject any v2 blocks - causing a fork between V2 and V3 nodes. ...
6
votes
1answer
81 views

What level of mathematical understanding do I need in order to contribute or to understand the crypto behind bitcoin?

My mathematical knowledge is up to CALC II (college level.) Is this enough mathematical maturity in order to understand the crypto in bitcoin or do I need more knowledge? If I do indeed need more ...
14
votes
4answers
901 views

Is a private blockchain better in any sense than a database?

Since the banks appear to be currently looking into the idea of "blockchains" but don't want to be dealing with "Bitcoin", it seems that there is a lot of hype for private blockchains out there like ...

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