The best Bitcoin Clients for Ubuntu - Multibit, Armory and ...

I currently have some Mastercoins associated with an address held in my Bitcoin-QT client. Can I import that wallet into electrum or multibit and still have control of the Mastercoins?

submitted by puck2 to mastercoin [link] [comments]

In early 2013, it became a common belief that new Bitcoin users should not be recommended Bitcoin-QT, the full node client. Bitcoin.org was changed to no longer exclusively recommend it. Two years later, the block size conservatives are saying the drop in full node count was due to block size

I distinctly remember that the recommending of Bitcoin-QT to new Bitcoin users became a faux pas in early 2013. It was claimed that regular people should download and install an SPV client like Multibit.
Predictably, there was a large drop in the full node count, as the wallet market became dominated by a large number of new, light clients, and the most trafficked Bitcoin website, bitcoin.org, stopped exclusively recommending people to install Bitcoin-QT.
Now, we have important developers like Luke-Jr claiming that this 95% drop in full node count can be mainly attributed to the growing size of the block chain, despite the fact that the drop began right when light clients began being recommended..
EDIT to add some data:
This is the image that GMaxwell and Peter Todd, two individuals who are conservative about the block size (in particular Peter Todd, who's been warning about increasing the 1 MB size limit since 2013), have linked to to make their point about the full node count:
http://i.imgur.com/EL0zHRe.jpg
Up until at least March 18, 2013, the only client recommended to visitors of bitcoin.org was Bitcoin-QT, and an installation link for it was provided right on the landing page:
https://web.archive.org/web/20130318211940/http://bitcoin.org/
The WayBack Machine shows that by March 25th, 2013, this had changed, and a 'Choose Your Wallet' button appeared on Bitcoin.org/:
https://web.archive.org/web/20130513214959/http://bitcoin.org/en/
From March 25th 2013 onward, the number of non-full-node wallets recommended by bitcoin.org increased, in response to a general increase in the number of high quality and/or well marketed light and mobile wallets on the market.
Now a days, Bitcoin-QT is one of twelve clients displayed on bitcoin.org's Choose Your Wallet page:
https://bitcoin.org/en/choose-your-wallet
Other than Bitcoin-QT and Bitcoin Armory, all of them are non-full-node clients.
This shift, from a wallet market where only Bitcoin-QT was available and recommended to one that is increasingly diverse and dominated by light clients, coincides with the point (Spring 2013) where we start seeing a rapid decline in the full node count.
submitted by aminok to Bitcoin [link] [comments]

PSA: Clearing up some misconceptions about full nodes

It's time to clear up some misconceptions floating around about full nodes.
Myth: There are only about 5500 full nodes worldwide
This number comes from this site and it measured by trying to probe every nodes on their open ports.
Problem is, not all nodes actually have open ports that can be probed. Either because they are behind firewalls or because their users have configured them to not listen for connections.
Nobody knows how many full nodes there are, since many people don't know how to forward ports behind a firewall, and bandwidth can be costly, its quite likely that the number of nodes with closed ports is at least another several thousand.
Nodes with open ports are able to upload blocks to new full nodes. In all other ways they are the same as nodes with closed ports. But because open-port-nodes can be measured and closed-port-nodes cannot, some members of the bitcoin community have been mistaken into believing that open-port-nodes are that matters.
Myth: This number of nodes matters and/or is too low.
Nodes with open ports are useful to the bitcoin network because they help bootstrap new nodes by uploading historical blocks, they are a measure of bandwidth capacity. Right now there is no shortage of bandwidth capacity, and if there was it could be easily added by renting cloud servers.
The problem is not bandwidth or connections, but trust, security and privacy. Let me explain.
Full nodes are able to check that all of bitcoin's rules are being followed. Rules like following the inflation schedule, no double spending, no spending of coins that don't belong to the holder of the private key and all the other rules required to make bitcoin work (e.g. difficulty)
Full nodes are what make bitcoin trustless. No longer do you have to trust a financial institution like a bank or paypal, you can simply run software on your own computer. To put simply, the only node that matters is the one you use
Myth: There is no incentive to run nodes, the network relies on altruism
It is very much in the individual bitcoin's users rational self interest to run a full node and use it as their wallet.
Using a full node as your wallet is the only way to know for sure that none of bitcoin's rules have been broken. Rules like no coins were spent not belonging to the owner, that no coins were spent twice, that no inflation happens outside of the schedule and that all the rules needed to make the system work are followed (e.g. difficulty.) All other kinds of wallet involve trusting a third party server.
All these checks done by full nodes also increase the security. There are many attacks possible against lightweight wallets that do not affect full node wallets.
This is not just mindless paranoia, there have been real world examples where full node users were unaffected by turmoil in the rest of the bitcoin ecosystem. The 4th July 2015 accidental chain fork effected many kinds of wallets. Here is the wiki page on this event https://en.bitcoin.it/wiki/July_2015_chain_forks#Wallet_Advice
Notice how updated node software was completely unaffected by the fork. All other wallets required either extra confirmations or checking that the third-party institution was running the correct version.
Full nodes wallets are also currently the most private way to use Bitcoin, with nobody else learning which bitcoin addresses belong to you. All other lightweight wallets leak information about which addresses are yours because they must query third-party servers. The Electrum servers will know which addresses belong to you and can link them together. Despite bloom filtering, lightweight wallets based on BitcoinJ do not provide much privacy against nodes who connected directly to the wallet or wiretappers.
For many use cases, such privacy may not be required. But an important reason to run a full node and use it as a wallet is to get the full privacy benefits.
Myth: I can just set up a node on a cloud server instance and leave it
To get the benefits of running a full node, you must use it as your wallet, preferably on hardware you control.
Most people who do this do not use a full node as their wallet. Unfortunately because Bitcoin has a similar name to Bittorrent, some people believe that upload capacity is the most important thing for a healthy network. As I've explained above: bandwidth and connections are not a problem today, trust, security and privacy are.
Myth: Running a full node is not recommended, most people should use a lightweight client
This was common advice in 2012, but since then the full node software has vastly improved in terms of user experience.
If you cannot spare the disk space to store the blockchain, you can enable pruning. In Bitcoin Core 0.12, pruning being enabled will leave the wallet enabled. Altogether this should require less than 900MB of hard disk space.
If you cannot spare the bandwidth to upload blocks to other nodes, there are number of options to reduce or eliminate the bandwidth requirement. These include limiting connections, bandwidth targetting and disabling listening. Bitcoin Core 0.12 has the new option -blocksonly, where the node will not download unconfirmed transaction and only download new blocks. This more than halves the bandwidth usage at the expense of not seeing unconfirmed transactions.
Synchronizing the blockchain for a new node has improved since 2012 too. Features like headers-first and libsecp256k1 have greatly improved the initial synchronization time.
It can be further improved by setting -dbcache=3000 which keeps more of the UTXO set in memory. It reduces the amount of time reading from disk and therefore speeds up synchronization. Tests showed that the entire blockchain can now be synchronized in less than 3 and a half hours (Note that you'll need Bitcoin Core 0.12 or later to get all these efficiency improvements) Another example with 2h 25m
How to run a full node as your wallet.
I think every moderate user of bitcoin would benefit by running a full node and using it as their wallet. There are several ways to do this.
So what are you waiting for? The benefits are many, the downsides are not that bad. The more people do this, the more robust and healthy the bitcoin ecosystem is.
Further reading: http://www.truthcoin.info/blog/measuring-decentralization/
submitted by belcher_ to Bitcoin [link] [comments]

Secure paper wallet tutorial

This is my handout for paranoid people who want a way to store bitcoin safely. It requires a little work, but this is the method I use because it should be resistant to risks associated with:
  1. Bad random number generators
  2. Malicious or flawed software
  3. Hacked computers
If you want a method that is less secure but easier, skip to the bottom of this post.
The Secure Method
  1. Download bitaddress.org. (Try going to the website and pressing "ctrl+s")
  2. Put the bitaddress.org file on a computer with an operating system that has not interacted with the internet much or at all. The computer should not be hooked up to the internet when you do this. You could put the bitaddress file on a USB stick, and then turn off your computer, unplug the internet, and boot it up using a boot-from-CD copy of linux (Ubuntu or Mint for example). This prevents any mal-ware you may have accumulated from running and capturing your keystrokes. I use an old android smart phone that I have done a factory reset on. It has no sim-card and does not have the password to my home wifi. Also the phone wifi is turned off. If you are using a fresh operating system, and do not have a connection to the internet, then your private key will probably not escape the computer.
  3. Roll a die 62 times and write down the sequence of numbers. This gives you 2160 possible outcomes, which is the maximum that Bitcoin supports.
  4. Run bitaddress.org from your offline computer. Input the sequence of numbers from the die rolls into the "Brain Wallet" tab. By providing your own source of randomness, you do not have to worry that the random number generator used by your computer is too weak. I'm looking at you, NSA ಠ_ಠ
  5. Brain Wallet tab creates a private key and address.
  6. Write down the address and private key by hand or print them on a dumb printer. (Dumb printer means not the one at your office with the hard drive. Maybe not the 4 in 1 printer that scans and faxes and makes waffles.) If you hand copy them you may want to hand copy more than one format. (WIF and HEX). If you are crazy and are storing your life savings in Bitcoin, and you hand copy the private key, do a double-check by typing the private key back into the tool on the "Wallet Details" tab and confirm that it recreates the same public address.
  7. Load your paper wallet by sending your bitcoin to the public address. You can do this as many times as you like.
  8. You can view the current balance of your paper wallet by typing the public address into the search box at blockchain.info
  9. If you are using an old cell phone or tablet do a factory reset when you are finished so that the memory of the private keys is destroyed. If you are using a computer with a boot-from-CD copy of linux, I think you can just power down the computer and the private keys will be gone. (Maybe someone can confirm for me that the private keys would not be able to be cached by bitaddress?)
  10. To spend your paper wallet, you will need to either create an offline transaction, or import the private key into a hot wallet. Creating an offline transaction is dangerous if you don't know what you are doing. Importing to a client side wallet like Bitcoin-Qt, Electrum, MultiBit or Armory is a good idea. You can also import to an online wallet such as Blockchain.info or Coinbase.
Trusting bitaddress.org
The only thing you need bitaddress.org to do is to honestly convert the brainwallet passphrase into the corresponding private key and address. You can verify that it is doing this honestly by running several test passphrases through the copy of bitaddress that you plan on using, and several other brainwallet generators. For example, you could use the online version of bitaddress, and brainwallet and safepaperwallet and bitcoinpaperwallet. If you are fancy with the linux command line, you can also try "echo -n my_die_rolls | sha256sum". The linux operating system should reply with the same private key that bitaddress makes. This protects you from a malicious paper wallet generator.
Trusting your copy of bitaddress.org
Bitaddress publishes the sha1 hash of the bitaddress.org website at this location:
https://www.bitaddress.org/pgpsignedmsg.txt
The message is signed by the creator, pointbiz. I found his PGP fingerprint here:
https://github.com/pointbiz/bitaddress.org/issues/18
"527B 5C82 B1F6 B2DB 72A0 ECBF 8749 7B91 6397 4F5A"
With this fingerprint, you can authenticate the signed message, which gives you the hash of the current bitaddress.org file. Then you can hash your copy of the file and authenticate the file.
I do not have a way to authenticate the fingerprint itself, sorry. According to the website I linked to, git has cryptographic traceability that would enable a person to do some research and authenticate the fingerprint. If you want to go that far, knock yourself out. I think that the techniques described in this document do not really rely on bitaddress being un-corrupt. Anyway, how do we know pointbiz is a good guy? ;-)
There are a lot of skilled eyes watching bitaddress.org and the signed sha1 hash. To gain the most benefit from all of those eyes, it's probably worthwhile to check your copy by hashing it and comparing to the published hash.
"But we aren't supposed to use brainwallets"
You are not supposed to use brainwallets that have predictable passphrases. People think they are pretty clever about how they pick their passphrases, but a lot of bitcoins have been stolen because people tend to come up with similar ideas. If you let dice generate the passphrase, then it is totally random, and you just need to make sure to roll enough times.
How to avoid spending your life rolling dice
When I first started doing this, I rolled a die 62 times for each private key. This is not necessary. You can simply roll the die 62 times and keep the sequence of 62 numbers as a "seed". The first paper address you create would use "my die rolls-1" as the passphrase, the second would be "my die rolls-2" and so on. This is safe because SHA256 prevents any computable relationship between the resulting private key family.
Of course this has a certain bad security scenario -- if anyone obtains the seed they can reconstruct all of your paper wallets. So this is not for everyone! On the other hand, it also means that if you happen to lose one of your paper wallets, you could reconstruct it so long as you still had the seed.
One way to reduce this risk is to add an easy to remember password like this: "my die rolls-password-1".
If you prefer, you can use a technique called diceware to convert your die rolls to words that still contain the same quantity of entropy, but which could be easier to work with. I don't use diceware because it's another piece of software that I have to trust, and I'm just copy/pasting my high entropy seed, so I don't care about how ugly it is.
Why not input the dice as a Base 6 private key on the Wallet Details tab?
Two reasons. First of all, this option requires that you roll the die 99 times, but you do not get meaningful additional protection by rolling more than 62 times. Why roll more times if you don't have to? Second, I use the "high entropy seed" method to generate multiple private keys from the same die rolls. Using the Base 6 option would require rolling 99 times for every private key.
I'm a big nerd with exotic dice. How many times to roll?
Put this formula in Excel to get the number of times to roll: "=160*LOG(2,f)" where f = number of faces on the die. For example, you would roll a d16 40 times. By the way, somewhat unbelievably casino dice are more fair than ordinary dice
The "Change address" problem:
You should understand change addresses because some people have accidentally lost money by not understanding it.
Imagine your paper wallet is a 10 dollar bill. You use it to buy a candy bar. To do this you give the cashier the entire 10 dollar bill. They keep 1 dollar and give you 9 dollars back as change.
With Bitcoin, you have to explicitly say that you want 9 dollars back, and you have to provide an address where it should go to. If you just hand over the 10 dollar bill, and don't say you want 9 dollars back, then the miner who processes the transaction gives 1 dollar to the store and keeps the remainder themselves.
Wallet software like Bitcoin-Qt handles this automatically for you. They automatically make "change addresses" and they automatically construct transactions that make the change go to the change address.
There are three ways I know of that the change problem can bite you:
  1. You generate a raw transaction by hand, and screw up. If you are generating a transaction "by hand" with a raw transaction editor, you need to be extra careful that your outputs add up to the same number as your inputs. Otherwise, the very lucky miner who puts your transaction in a block will keep the difference.
  2. You import a paper wallet into a wallet software and spend part of it, and then think that the change is in the paper wallet. The change is not in the paper wallet. It is in a change address that the wallet software generated. That means that if you lose your wallet.dat file you will lose all the change. The paper wallet is empty.
  3. You import a paper wallet into a wallet software and spend part of it, and then think that the change is in the change address that the wallet software generated. If the transaction did not need to consume all of the "outputs" used to fund the paper wallet, then there could be some unspent outputs still located at the address of the paper wallet. If you destroyed the paper wallet, and destroyed the copy of the private key imported to the wallet software, then you could not access this money. (E.g. if you restored the software wallet from its seed, thinking all of the money was moved to the wallet-generated change addresses.)
For more on this, see here
The hot paper wallet problem
Your bitcoin in your paper wallet are secure, so long as the piece of paper is secure, until you go to spend it. When you spend it, you put the private key onto a computer that is connected to the internet. At this point you must regard your paper wallet address as hot because the computer you used may have been compromised. It now provides much less protection against theft of your coins. If you need the level of protection that a cold paper wallet provides, you need to create a new one and send your coins to it.
Destroying your paper wallet address
Do not destroy the only copy of a private key without verifying that there is no money at that address. Your client may have sent change to your paper wallet address without you realizing it. Your client may have not consumed all of the unspent outputs available at the paper wallet address. You can go to blockchain.info and type the public address into the search window to see the current balance. I don't bother destroying my used/empty paper wallet addresses. I just file them away.
Encrypting your private key
BIP 0038 describes a standardized way to encrypt your paper wallet private key. A normal paper wallet is vulnerable because if anyone sees the private key they can take the coins. The BIP38 protocol is even resistant to brute force attacks because it uses a memory intensive encryption algorithm called scrypt. If you want to encrypt your wallets using BIP38, I recommend that you use bitcoinpaperwallet because they will let you type in your own private key and will encrypt it for you. As with bitaddress, for high security you should only use a local copy of this website on a computer that will never get connected to the internet.
Splitting your private key
Another option for protecting the private key is to convert it into multiple fragments that must be brought together. This method allows you to store pieces of your key with separate people in separate locations. It can be set up so that you can reconstitute the private key when you have any 2 out of the 3 fragments. This technique is called Shamir's Secret Sharing. I have not tried this technique, but you may find it valuable. You could try using this website http://passguardian.com/ which will help you split up a key. As before, you should do this on an offline computer. Keep in mind if you use this service that you are trusting it to work properly. It would be good to find other independently created tools that could be used to validate the operation of passguardian. Personally, I would be nervous destroying the only copy of a private key and relying entirely on the fragments generated by the website.
Looks like Bitaddress has an implementation of Shamir's Secret Sharing now under the "Split Wallet" tab. However it would appear that you cannot provide your own key for this, so you would have to trust bitaddress.
Durable Media
Pay attention to the media you use to record your paper wallet. Some kinds of ink fade, some kinds of paper disintegrate. Moisture and heat are your enemies.
In addition to keeping copies of my paper wallet addresses I did the following:
  1. Order a set of numeric metal stamps. ($10)
  2. Buy a square galvanized steel outlet cover from the hardware store ($1)
  3. Buy a sledgehammer from the hardware store
  4. Write the die rolls on the steel plate using a sharpie
  5. Use the hammer to stamp the metal. Do all the 1's, then all the 2's etc. Please use eye protection, as metal stamp may emit sparks or fly unexpectedly across the garage. :-)
  6. Use nail polish remover to erase the sharpie
Electrum
If you trust electrum you might try running it on an offline computer, and having it generate a series of private keys from a seed. I don't have experience with this software, but it sounds like there are some slick possibilities there that could save you time if you are working with a lot of addresses.
Message to the downvoters
I would appreciate it if you would comment, so that I can learn from your opinion. Thanks!
The Easy Method
This method is probably suitable for small quantities of bitcoin. I would not trust it for life-altering sums of money.
  1. Download the bitaddress.org website to your hard drive.
  2. Close your browser
  3. Disconnect from the internet
  4. Open the bitaddress.org website from your hard drive.
  5. Print a paper wallet on your printer
  6. Close your browser
submitted by moral_agent to BitcoinWallet [link] [comments]

How trustworthy are the authors of Electrum and MultiBit ? Why are their signing keys not verified?

Hello,
I was a bit alarmed by these two posts some weeks ago:
http://www.reddit.com/Bitcoin/comments/210fgj/there_is_an_pgp_imposter_of_bitcoin_dev_gavin/
http://www.reddit.com/Bitcoin/comments/1tin7f/warning_a_fake_electrum_website_with_malware_is/
In the first case, basically somebody registered a PGP key which at first glance looked like the signing key from Gavin Andresen. Such a key could be used to sign malware which appears as the true bitcoin client. This would only be detected if people check carefully. If people do NOT check it - maybe rushing in a situation where the network needs a quick fix - the consequences could be truly disastrous.
In the second case, the Electrum website was actually faked to distribute malware which was camouflaged as the Electrum client. If people install such a client, it could send their bitcoins anywhere - this kind of attack can really cause a lot of grief, too.
Note that in some simple setups, it might be possible to recognize the faked web site by its address, but in other cases, this will not be possible - think of insidious attacks on home routers or exploits of the recent Apple "goto" bug, which essentially disables SSL protection.
In these cases, and whenever youinstall bitcoin software, it is always important to check for digital signatures of the maintainers, which can warrant the authenticity of the code. And, doing this properly includes verification of their keys.
To make it short, I was newly installing Electrum and I decided to do it right and to look after the digital signatures and whether the signatures properly certified in a web of trust. Now, trust paths can be looked up by databases like these:
http://pgp.cs.uu.nl/
It works so that in the "from" field, you enter YOUR key ID (which needs to be connected to the web of trust graph). In the "to" field, you enter the key ID of the signing key for the software. Now, you should be able to find at least one trust path from you to the signing key for the software. For example, if Mark Shuttleworth wants to verify the key of Gavin Andresen, he enters his key ID: D54F0847 into the "from" field, and Gavin's key - 1FC730C1 - into the "to" field. This will look as here:
http://pgp.cs.uu.nl/mk_path.cgi?FROM=D54F0847&TO=1FC730C1&PATHS=trust+paths
The trouble is, if Mark looks up the key for ThomasV, this looks so:
http://pgp.cs.uu.nl/mk_path.cgi?FROM=D54F0847&TO=7F9470E6&PATHS=trust+paths
that is currently, no trust paths to ThomasV's key are found. The same is true for Jim Burton, maintainer of Multibit.
In other words, ThomasV's key cannot be verified, if somebody does not has other means. Well, somebody could look into the bitcoin forum - but first, the forum can be and has been hacked. And second, a forum identity does not mean much. Pirateat40 had an account, too, as well as the owner of bitcoinica.
I do not suspect the developers of working in an evil plot, but honestly, I'd really like to know a bit more.
Now, I have a few questions:
Thanks!
Edit: A few developers have posted here... can other people confirm what they say? Can it be proven? Anyone was at that conference?
Edit: As an important clarification: The fact that a key can be found on a keyserver, is signed by some entity, or is contained in the "strong set" of the PGP web of trust or in any web of trust does not necessarily imply that the key is linked to an authentic identity, end even less that the owner is a good guy. It only provides a mean to check this identity and to support the assumption that the identity is correct, independent from hacking attempts.
And as a reply to some badly downvoted comment: Yes, knowing or probably knowing the identity of the auhtor of some code is by no means a substitute for skilled people carefully checking the code and any change in it.
submitted by DrunkRaven to Bitcoin [link] [comments]

I have a Bitcoinfession and a plea: Don't gamble.

Hi everyone, I know very few people will see this and that's okay. I decided after a week of severe depression, anxiety, self-loathing, and general fucked up thoughts that I needed to talk about what I did. On the scope of a confession, it isn't much to some people, but to me it is a huge and daunting fuck up that I'll be paying out the nose for. The reality is I might even be homeless due to this. I used a throwaway for this because a few people I know have my primary acct and I can't bear the shame of them knowing yet.
To get to it, I made a huge mistake and lost all my money. ALL OF IT.
If it isn't obvious already, I don't have a lot of money. I am not a all that familiar with bitcoin and only recently began taking part in the community. /Bitcoin has been my bible and go to source nearly every day for the last 6 months. But again, I don't have much money and I decided that I have a this tremendously good feeling about where bitcoin is going so I warily invested in a couple coins around January 2nd at about 809 a coin from coinbase. I was terrified of losing what I put in. Then the next day, the price jumped about $30! I was ecstatic! I was amazed! I couldn't believe that my investment had begun working for me after only a day! It was a great feeling.
At the same time of all this, I had just finsihed up a huge ordeal with Bank of America over fradulent charges on my debit card that sent my account into the negative and had intitially accured almost $1000 in overdraft and other fees. It took months to get all my money back and in the end still lost out on about $200 dollars. Needless to say, I was more wary of my bank than bitcoin at this point and bitcoin was GIVING me money instead of giving it away. So I did the only logical thing I could think of at the time and put the rest of my savings into BTC.
And guess what? It went up again! I was so happy with my decision that I started reading more and more about BTC.
Then the fluctuations in the BTC market started happening. I started to get nervous because the only cash I had was losing value and fast. I knew that it had a habit of fluctuating like that but I never had any money invested before. The anxiety was real for me every day I'd hop on /Bitcoin and see the news about mtgox ( then after that the silkroad 2 hack.)
So, about a week ago when coinbase's price was plummeting still due to gox's problems and bad press and so on I started getting nervous. More nervous than I had been before. My "investment" had lost almost 200 a coin and I was sick to my stomach watching and waiting for the price to come back up like it "always" does.
I was posting around a few forums and asking questions about what I should do? What could I do in the mean time? Should I pull out and take my losses? I got to talking to this guy on one of the forums who seemed to know what he was talking about. He mentioned the dice site satoshi bones and how he was in the same spot as me, made one bet and came out 10BTC richer. Even sent the tx ids. It was awesome to see and was even more awesome to imagine. He went as far as to send me .05 btc (holy shit!) and said "Make a few bets and watch, some of the odds are great."
So I did that. I sent a few bets of .001btc and made nearly .5 btc in 5 minutes. I was hooked. I was going to make my money back. I was going to make a few bets and get out with what I put in, no more.
So I proceeded to make bigger bets. I was making money. I was getting good at watching and "considering the odds." It wasn't really the case, I was just geting lucky here and there. I had no idea what the fuck I was doing.
Then the transaction malleability thing happened. Or, rather, it was probably happening the whole time. I don't know. I don't know what it did to my MultiBit account, but it was sending my coins and not updating my balance. I was losing more than I knew because the double spends ended up looking like I had more in my overall account than I did. At one point, it appeared that I had TRIPLED my initial BTC investment over all and I was nearly crying with joy.
Then I couldn't access my funds. It said I had a "Balance" of 30btc, but "Spendable" was .05. I knew that it took a little while for the transactions to get through the system and clear but minutes turned into hours and hours into days.
When the whole story about the transaction malleability broke into full swing I started tracing my tx IDs back. I was a nervous wreck at that point. I had so many double spends and unconfirmed transactions that there was no way to actually find out how much I truly had left. When I looked through multibit's logs, it had mulitples of the "wins" that I knew I had but numerous tx Ids. I couldn't keep track of it all. Attempting to "reset" the blockchain on Multibit would only cause it to crash (probably because I had sent and received sooooo many unconfirmed transactions back and forth between that game.)
I decided to grab my private keys and attempt to use Bitcoin-QT to sort it all out to no avail. It too said I had a balance around 30 BTC unconfirmed (a mind blowing amount of money for me!!!!!) I relaxed and decided I would just have to wait it out to get my money and I'd hold off on grocery shopping until the weekend (today.) Even if I had half of that after it all cleared up, I'd have made a HUGE profit.
About two days ago everything calmed down and my balance began fluctuating like mad on both the Multibit client and Bitcoin-qt. It went UP at one point to 40 BTC even! Then transactions started to disappear. Mostly, the transactions that disappeared were the "wins." I assume this is because all of the unconfirmed txs or double spends started being pushed out of the system? I have no idea.
I'll take a second to mention that I've never had an interest in gambling whatsoever. I've been to vegas, played a few slots, sat in for some poker and blackjack, would lose and just walk away. However, the last couple days I was consumed by the dice game. I thought I was making incredible money, hand over fist.
Yesterday, my balance completely cleared up. I'm broke. I have nothing left. I pissed away even my winnings (maybe 3btc) I had before the transaction malleability started fucking things up. I cried for the first time in 10 years yesterday. Today, I cried again.
Over the last week I fell into a depression and was overcome by this urge to just stop existing. Not really suicide at first, but, more of a "I want to close my eyes and let it all blow over." Then, when that didn't happen, I did start considering suicide. I have no money left. I don't know what the fuck I'm going to do for rent, for food, for gas, for my fucking books next quarter. I moved to california on my own about 3 years ago and have zero family in the area. I don't have family to lean on finacially whatsoever (I come from a seriously bad luck/misfortune/poor family.) Monday I'll be heading to my university to find out what I can do and if I qualify for any loans. Or something. I don't know. But right now, I need to tell people and persevere and try to make it out of this.
But, my point of posting here isn't a pity party or to draw out "sorry for the bad luck" responses. I did this to myself and this pales in comparison to the bad luck others have had.
I want people to use my sincere and obvious FUCK UP as a lesson. I got caught up thinking I was making money. I wasn't fully aware of what was happening during the transaction malleability shit and made decisions without fully comprehending the situation (and it is NOT the fault of Mulitbit or the dice game even if I wanted something to blame.) Most of all, I was GAMBLING my money away. It was greed and poor decisions. But mostly greed.
So, I fucked up. I don't want YOU to fuck up like I did. Please look at the story and realize that it can happen to anyone without fully thinking through your decisions and having a grasp on the situation. And SERIOUSLY consider when you're putting too much money at stake when gambling. You could regret it and be in a shitty spot like myself. Thanks for reading.
TL;DR Holy shit I wrote a novel. Sorry. In short, I inadvertently gambled away my only $7000 during the transaction malleability crisis and it is no one's fault but myself. I am now broke and terrified and I don't want YOU to suffer like I did. Do not gamble and do research before you do anything with your money especially if it is all you have.
EDIT: Though my intial reason for posting was NOT to focus on why my balance said one thing and the actual balance was another, here is what the balance looks like on my Multibit client right now. However if you look at the blockchain, that's clearly not the case and hasn't been for days and days. These are the addresses I used off and on. Not all of them but those were the most active I think. 17cHzgxRLumqfu6UAddUrJmTujd7goHLrx 1BAKHq37qj1xekitr7adXapLqFrVtAhm8A 1KLug6D1mXoyS12BZipyQ8WHAdNzDmQxMp. Also, when I opened the Client today it seemed to send or revieve "stuck" transactions? I don't know what to tell you all beyond that.
submitted by DontBeStupidLikeMe to Bitcoin [link] [comments]

Please ELI5: BIP 39/HD Wallets

Ok, so I "get" the bitcoin thing, just barely, and I have a few mBTC in my wallet - have even passed a few around as gifts! Got a couple iPhone apps working, played around with Multibit, the full QT client, web apps (coinbase and the like) etc. I have a Bitstamp account I haven't used yet, but bought a little on localbitcoins. Great. I'm now an expert. :) One day I might actually use it to buy something, who knows?
I don't have enough tied up in this economy to get to jazzed about backups - offline dedicated computers, cold-storage/paper-wallets, etc. But I get the idea well enough that, should I actually put real money into this thing, I can get that going. I was starting to study this a bit (paper wallets).
Then along comes Hive, the client for iOS and OS X. It has this magical "BIP 39" thing. Apparently, it generates a 12-word passphrase (which, believe it or not, I've actually memorized!), and given that, (if I understand correctly) you don't actually need to worry about saving or backing up private keys anymore. Is that actually correct?! It seems too magical for me to believe, frankly.
So, this "deterministic wallet" thing - apparently, if you have the 12-word passphrase, it can somehow regenerate a "seed" for a private wallet key, re-spawing it from the ether, so you never need to store it or back it up?!?! Or am I misunderstanding?
I did try out my 12-word passphrase generated in Hive in another client, and, lo-and-behold, it worked! WTF?!?!
So, reddit, can you kindly explain, in non-mathemetician terms, how the fuck does this work? Is it magic? Keep in mind, I barely get the blockchain, decentralized transactional ledger concept, so that's where I'm at. Thanks!!!
submitted by be_bo_i_am_robot to Bitcoin [link] [comments]

Why don't more people use electrum?

Is it just me or do not many people use this client? I love it because after writing down the seed, I never have to worry about "losing" my keys. It's also extremely lightweight, really easy to set a password, and the UI looks pretty good.
My question is: why do people generally prefer using bitcoin-QT, which requires a full download of the block chain, or Multibit, which didn't make it easy to encrypt for a long time?
Edit: here is a link to the client site where you can learn more and download it: http://electrum.org/
Basically, it's a bitcoin client like bitcoin qt but your keys are deterministic ally generated from a seed AND the client sends transactions to servers instead of processing transactions itself (all encrypted), obviating the need to download the whole block chain. The benefit of generating keys from a seed is that remembering a seed is all that's necessary to back up the wallet. Want to run it on another computer? Just download electrum, input the seed, and all your bitcoins will be there ready to spend instantly.
submitted by iamn to Bitcoin [link] [comments]

I just saw this one and had a doubt, does wallet leaks my IP? Does vpn requires special config for wallet?

Avoid Thin Clients and Hosted Wallets
Almost all thin clients leak which addresses you own to whatever Simple Payment Verification (SPV) server they connect to. Thin clients do not store the blockchain locally. Instead, they query a single SPV server for the transactions that involve the addresses in your wallet. While this functionality is far more efficient and fast than parsing the blockchain locally, the trade-off is that every Bitcoin address you own is submitted to the SPV server.
Some thin clients, such as Multibit, have the capability of using bloom filters to help conceal which addresses you own by requesting extra transactions that don’t involve your wallet. However, Multibit currently favors efficiency over privacy and does not utilize bloom filters for address anonymization. The Electrum thin client doesn’t use bloom filters at all, so just like Multibit, any server you connect to knows every address that you own.
Hosted clients are even worse in terms of anonymity. All of your private and public keys reside on 3rd party servers, so it is trivial for the operator to know which Bitcoin addresses you own. Additionally, any other information you’ve submitted to the service is associated with your Bitcoin addresses and can be easily accessed by the service’s operators.
These types of wallets make it easy for a SPV server operator or service administrator to not only know which Bitcoin addresses you own, but also associate them with your IP address. The operator could potentially publish the information, they could be hacked and the info stolen, or they could be subpoenaed or NSL’d to provide logs to law enforcement or government agencies.
One of the fundamentals of Bitcoin is not having to trust any single party. In terms of anonymity, it’s best to use a full Bitcoin client like Bitcoin-Qt or Armory, and store the entire blockchain locally.
tl;dr; Thin clients and hosted wallets leak which addresses you own — use a full client like Bitcoin-Qt or Armory instead.
source: https://99bitcoins.com/know-more-using-bitcoin-anonymously/
submitted by Ruban28 to Bitcoin [link] [comments]

Frustrated with wallets - could THIS be the stake through the heart of Bitcoin?

Actually, that should be "with wallets and fees." Both are causing some grief right now.
While in the process of building a new computer, I'm getting increasingly frustrated with Bitcoin's complexity, especially around the notion of wallets.
The Bitcoin-QT wallet becomes part of the network. Lovely, if you have a huge chunk of disk space to devote. I happen to be running a very lightweight pure SSD system, so onwards I look.
Hmm. Armory? Well, it sits on top of the QT client, so no.
How about Electrum? Not bad, but I'd rather NOT have my wallet stored elsewhere, encrypted or not. If I'm going to do that, I might as well just use a web wallet.
Multibit? Ah, here we go! Local storage, no downloading of the entire block chain, and...you can't alter the transaction fee! I wasn't going to stress out over that because as many people have said, "what's $0.25" (or .40 or .06, or whatever people claim the trivial fee is)?
But when I went to transfer my bitcoins from the old computer to the new one (because of course the wallet formats are incompatible between wallets), it came up with a fee of just under 0.05 BTC! I understand why fees are going to become important, but really - twenty bucks to transfer my own bitcoins from one computer to another, with the promise of more fees down the line.
This is not a good system; and the fact that everyone who wants to use bitcoin has to go through pages of documentation to get some vague understanding of why they have to pay nondeterministic fees sometimes and not other times.
Just venting here. This won't be the future of currency until it works as easily as currency.
submitted by swordgeek to Bitcoin [link] [comments]

Accepting bitcoin for my online business, do I need full validation for pre-generated addresses?

So, I've had the multibit client for a while, and I used to use bitpay as a payment gateway that funneled funds to one address. Now I'm revisiting accepting bitcoin through some websites.
As far as I can tell it's a bad idea to receive funds on one address, is this negated by the way bitpay works?
If I was to go down the route of pre-generating addresses do I need a different wallet as I can't see a way of importing pre-generated addresses into my wallet, or am I wrong? Do I need a wallet with full validation to do this?
I originally had the QT wallet but downloading the blockchain was a pain, and unless I kept the wallet online updating took a while also. Any wallets that anyone could recommend would be appreciated.
submitted by me__uk to Bitcoin [link] [comments]

Importing Private keys into a QT based wallet, how is it done?

Before the fork I had been storing my tokens in MultiBit. I saw no need to incur a transaction fee to transfer those tokens into a QT compatible wallet format prior to the fork. So now I am here with multiple files that contain the private key(s) from those wallets.
I now need to import these keys into both my Bitcoin (Cash) and Bitcoin (Settlement) QT clients. What are the steps necessary to accomplish this?
I did find https://bitcointalk.org/index.php?topic=336404.0
Is this a safe method in which to perform the activity? I will be importing to Bitcoin ABC v0.14.6 & Bitcoin Unlimited v1.0.3.0
  1. Export private key from MultiBit without password (Done)
  2. edit file with some editor like Notepad++ (I'll probably just use Notepad, unless that is a bad idea?)
  3. copy only key - this is row without # ,and you must copy only key - no date and another symbols , (row indicates that it might be better to import to a spreadsheet?)
  4. then in BitCoin-Qt open from Help->Debug window ->Console (I am able to navigate to where the Console is not located)
  5. importprivkey [label] [rescan=true]
(Where is the information I copied from step 3? and also without the '<>')
(where label is name of owner - your name.; is this necessary? Do I need to provide a label? Can I leave it blank? And if I can leave it blank would I simply omit that the '[label]' argument?)
  1. And when press enter the your address with coins will appear in your addresses and in your balance.
Additionally, can this activity take place on a computer that is not connected to the applicable network? I am still waiting (1 year 40 weeks behind) for the Bitcoin (Settlement) wallet to download the chain (for some reason copying over of the pre-fork blocks did not take and now that the fork has occurred I do not want to try to start over or run the risk of re-installing).
Thank you for your assistance.
submitted by PilgramDouglas to btc [link] [comments]

GPG instructions and public key list for verifying Bitcoin clients.

I have noticed their is a growing problem of fake bitcoin clients, and I expect the frequency and elaboratness of these fake clients to increase.
Verifying the signatures for these clients will detect if you are receiving anything other than what the signer the of the software signed. The exception to this is if the attacker acquires the signer's private key, which should be a lot more difficult than tricking users to visit the wrong site or hacking servers. This can also be addressed by using multiple signatures per client.
An important part of this process is acquiring the public keys for the sofware signers in a secure manner.
To help with this I have included a signed list of fingerprints and where to acquire the public keys to act as another source to verify the keys used to sign bitcoin clients.
I have also included instructions for verifying the fingerprint list and bitcoin clients.
To deal with the issue that posts and comments on Reddit can be easily modified I suggest other users (especially well known ones) post a signature of the fingerprint list in a comment in this thread, or at least a hash of the fingerprint list (not as secure but still better than nothing).
List of Fingerprints:
+++ Bitcoin-Qt: Signer: Gavin Andresen (CODE SIGNING KEY) [email protected] Fingerprint: 2664 6D99 CBAE C9B8 1982 EF60 29D9 EE6B 1FC7 30C1 Key ID: 1FC730C1 Key Link: bitcoin.org/gavinandresen.asc
Electrum: Signer: ThomasV [email protected] Fingerprint: 6694 D8DE 7BE8 EE56 31BE D950 2BD5 824B 7F94 70E6 Key ID: 7F9470E6 Keyserver: pool.sks-keyservers.net Signer: Animazing [email protected] Fingerprint: 9914 864D FC33 499C 6CA2 BEEA 2245 3004 6955 06FD Key ID: 695506FD Keyserver: pool.sks-keyservers.net
Multibit: Signer: Jim Burton (multibit.org developer) [email protected] Fingerprint: 299C 423C 672F 47F4 756A 6BA4 C197 2AED 79F7 C572 Key ID: 79F7C572 Keyserver: pgp.mit.edu
Armory: Signer: Alan C. Reiner (Offline Signing Key) [email protected] Fingerprint: 821F 1229 36BD D565 366A C36A 4AB1 6AEA 9883 2223 Key ID: 98832223 Keyserver: pgp.mit.edu +++
My Key:
-----BEGIN PGP PUBLIC KEY BLOCK----- Version: GnuPG v1.4.12 (GNU/Linux) mQINBFLB9nUBEAC/klZvqQkWP/NUD0pT09PzhKh0xIQ0XM7MxqUZLa1OytF3iUCX /fNwQD5OnSFQoEg1O4bGzrrRb+PiuKCvH19dp7sFVj3q7Dhwfb6EvsX39xqzxCr6 2AQFQ3esz4nNodnQWa48t2ujihaf/vpTn6n7+jCl6a124r+U4wNGiNIEWxLLUNNb ec8S1RcjtTp6Ue/yRpThgJN9e4rj19+vJMqKCiqL03NBZWVoCEkL6iIdjwlQK8/r CpP9m5yAsc8wkelRkZvuLmjJ1GgSFrO0WteGnURMshy59LetaSRyiIDeHaPdV5rk /n3mBv8hsK/39O6H7fYWDx/ZLnZE4rMghcndexIFLhsuPx6FJNATqQ2gHT4ijb8K NlwZ0LatlXyUEMKfC1aroa3/9RkQSf0y0GKS0XrvUWGVRn/X7gk1DRhuaHWuacCf k3w0XZOA2WpWw1w/rjZSeHbKG1w4B2/kWH3K4sXsfcLltlY85zH03HUYSx+leMFc yxiHz60ZfuV2aGjYFPL8dzF6DS106lHz51j608OZkAEO8Xssincii1k/PR1h1y2P AqgrEADzgl52iBbNw+tdnxSAIy/asEyxU/VwkUFjOzSyP7ZmBxg8ss966w2Kl6WE o9R5tkVuUG8WTMTnF0FeMxO9YOqx4KhN9bhP7RjBL7BFTvRXYVVJUGabIQARAQAB tBVkY2M0ZSA8ZGNjNGVAZ214LmNvbT6JAj4EEwECACgFAlLB9nUCGwMFCQlmAYAG CwkIBwMCBhUIAgkKCwQWAgMBAh4BAheAAAoJECO6L0dAOWOhsNIQAKUN9Z4e0hM3 DbaUjYJx93JGdJArLmz+Ko10N/lGcao4lCNVA+xM73Ga1GBnPlhPFW9iD2VQocOv tY2PYNsPrHgGlzyMKAMSpZ8364wVEyCHdJVKFORUjhyuJGYfyhDt2iZuzQwxWbmQ 1gmlbiGvxRysmaSW5+M8CDhja/fI8+EOp5NbH/EvHJClul3cO72UBUXBPxRv4Eb+ j8k0Uozob70A3bD894F8bJ9wZ3XBX/9DEkAbvDyW7CxIZwUiCeYTQylH++8S91A1 wL3z35ELdOLzGqwetYY6gSZRwY/W+rewEfPfBDSRjXKOBfhraMBYV1Sdg0IUj10W 2XVAzkqmqaej0T/xTt6aNjFtiH1u18BUpYIcCAAZ6TJ7325bnqnI+0xWFdonyggL +AIX1nzhx5niw8ZkCX0/jlJAx3TXAuxX/Tfy7cVSVi33v0fiwoDb8ZIDBzg0P2uc PUpR13B3AevFpxuAuAFPWfTDOJQmZyn9YNswVOhNb9rfq5bkmaSBlMRefTtUKIjW XjrRhSULPJ73H+R1DNL1Y0vhclnkOVCFRB+VPChkO+6RitGQDTg/Z60fBHpnYiDz sysnsoojLwBGanHO5mZMprxADc9CmeRGRmfHwvx7eJvW1HqN+5JR3Ai+JDlT+IxX RNUQxUbOry4D8TwRn9nBEtumNyNQcBmUuQINBFLB9nUBEACyRFYCrOXxC8yWm92U qPPNa3YC+W17O4rHW/thKTze1/TeZAKTNaIMPCS7iSVBBRbuijG+8NsgFd6W9acC ihMD4VUdFhVPjRGM3HmqzsxudVI4kGlQl8w86pYZu8ceGB4LQcoUFbPmWgXDIszH NV7kIFO/2oCRJ7VIBllUMP97RRdIfDND7EZMWvDveZ40BZCBLfnD9f6VSs4Lgn2C ow/ko01ijnvUxA/BGPJKI7JTLJHbdL//RQwT3AacLSc/etIurY2Ef926XbYYI1gi qboCU/dYUkGG2D+BDcGdukwpksdZZSXPyNhkZQAPPViHuFFtHI3C+FNb5L+lnC0h /dfF73U1lN3jp/VX11U1tIsHJyPjs8aael2UJO7Qy3vgVRM6KOywNNjVRv79Z/rF YHkNzBwXrGKdwV16SdRWjgkzkB4JeNQME096SqrwAEj/j5fwMqHjR8dKqWKDT6s9 V2Z83go3n9kI8JWFh33OksBh/qpKghhwtGWrUsbVcEDOVmUn2ozXvARDzqnNw3DN PcQvzUtasD8hxGHo7fW4TczdtgS3b/DfU2VJo68Fmo1C4eqYX+Ixx05khFCtP7d0 POqX6jIIQqZq8NTea8/M8Xx1YGhR5RpA4vZe7bCLgD2VUXHL43Npmq2nuZ0/7AwY H0hc/y/T+SU70xn28XyWHHLkCwARAQABiQIlBBgBAgAPBQJSwfZ1AhsMBQkJZgGA AAoJECO6L0dAOWOhIcgP/ioKYiJFAsolS4ep1PenCPvQFjvZTq4xJnsubEJ/ERU8 zdgET0Rh5jcCLqRAxQbGW3lVsewR3N+S9Rt3zHApqfZBFg5XJkZxsk0u+0qGPHWA 4oC7U3E4ZwMfVzUDcfKrzD1h0JaiSW1+1qgCh9/YVCUYakR1n/9LgzPP8ekQLTeb nWE+ZQQfeTDgoTNFWZvUlEbh4zcHLvcay78PnK3uT3UbWPyltSxon/eD47s1dt03 P/8nqaXCZhhRZ9N3EbJyudLBgA3ctySSJJSKKQHYynH5qUQqKp4Wq1KY80161xvW FqKwN/Jr4tTpRVZPu8P82cxhwrWJdf1U3/M2F2aIgXbGS4fHbzsLZ+6zZ3AuT4D8 auW55GOrnoF9XzZV6IavtluILUXMjVzF13slo5PKzS8yyJRNxE22krbeEyUum4Zu dDiERxIB6B+RDMM9qvV9svGJoEXG+4ugwkA3R7a6LWApmkvH3eXpULfDN2g5eNcr 5efFMrI/myxmpsP3nUp5EZFJyp8+ZSzIMJ1jSzXH8mHajIGTG49xDyZGpbog3wd2 7aQf5D9WOuKfYZM9MU9PBF+ZgtNrAxWuYJcCOr4WEd/2IjayMWvLxNA/RVW66oVj puaaDc3m3hXg1fwUWv9ZJyMUv7NARLgig3KEMVZiVzos7ZMn9mZNrOk2fnkKpVJB =ufyu -----END PGP PUBLIC KEY BLOCK----- 
Signature for fingerprint list:
-----BEGIN PGP MESSAGE----- Version: GnuPG v1.4.12 (GNU/Linux) owGFk31QFGUcx48XIU/KU0YSZOhHToraHeze3u4tqd2+HZ6g4ks6ZBTLsXdud7eH ewtCV4mp4/hGKmlTQbyEkgoZxpg6kReML0RWaoohOWWN0mhK4WSZje0Zxw0zzfTP 7rPf5zfP7/N8nn22PRyliYyYfDQ9y0La6yNaotYW6hyi5BTkYlmUFJ9BKVMWdZyu mDFjhpYWFbtXlPQLlUztYtEpCXImZPGlogSUVCQLPkGCNGYBy8FiW9Z82/wsyOby poEzWMEPFVicHl50G+xeD1jDXTIBxXEMcJYkgaEpDhiSNgNCmlHgrHgGoCRLAsfh NCBWhgBjBoNos4VysLGZD5LhIEeUXJlQ+C+nwSs700d0N/A+u5ZzC3ZFLvGE97Bk hdfD+5aC8uBdiqiQZYYiQTuCEMdJDFizujuC5swqjQkHI0JzwJImlZBmTWBGMRoI q1pHZHD4MGEwCQU+QS4Ntiz2et0Gn8und4Uyn0ESlGEkShI9/Etqf5jJh4Zhd7NH opEkgoEZx1iwMkYjYCTJAM5QKADNcRSgKGZSnWWogkmTCTJwKzvMFkxCwf+xzStx K6LqNixurugBukRWvOrBe4Zmg9ahSCgV3N5iQZ4GL4oeHDFbHLxPGcI3lLhG8qNB YAw1qtQEagWMsKoGTTgFOE1hwCAkASjFsUCQVgIYE4GG1apJKBjGdxYbPCqHUFSi pWSPVy4PA1NuXgLGAIsEUf2GtAUOh1sdQXA+KFtdZhrwapFl6B/iHywQdD4S2Ywi VkBQlAQjTrPAmnBVMa4iM0b1gVE0AjiluifNZqN6AKhxGDmYhIL/Qg5etI2RydGa iEhNzKjI4N3TaEfrQjf0brJOs692U9vbzb2jMs51uP1Jl/6KXf7NoTEHolxXvvRf SjzbEylrjFvH1jXefbJxd9/tK8u8SVdLC9yv5N88N/v1Cyu7N1deXDPJMeVs8obj b9zvtW84sv9OWeJJ8tXyPX2/N+zqGn+ZnxCdGz++QXqzYGzthSRE7JJaflRu4/01 jqsFuat62ifvHujc8ZhupW1P59OBjoMtgz+crx08mdN/sDkwtUmfLecN2Hb8duuz Lxq6Aztjz3RsWV1d3TJBc4D86cbfuqjvn0iJemqvfk1/ToHQFZhtWrT555eZwh45 +vNj/jX7Fubnd/3adNxf+EhF7sWmMX+Q184dSvygFdFXBF6b2m1KjLvnoKanzEp0 2cWqgX7L2biU8/2xt5LudZ4g4pawCZVpv6T7q1JfaN9Q1xFxP2Z55fiPuo7tvXdd v6m3vrLt+Tk12bGzDn/rr8+puxl4vLsqrnPKmPg51xUZo+tiXKuf2XZ44DLd8t7N weL21tONnY2jKy+MSzi1/1o8sWrQPPPTd1tteW/tTct6fyO2NNWUJ6wT6mPWx9fz 31ml53QTe75a+2HbumVuvZCcC33V0/fFpM07wkRYUh9a0LxzK6mrOuqYChWT6u4M oGkJS2vmNkWdmdWcP5le4ulLbr+Ws+IysX37OyfSt4y70St8vLov9dE/k3Y1zNy4 SyrY/fWzvRMLP8mNrjh1eFvtznXt/wA= =5zDz -----END PGP MESSAGE----- 
Hashes for fingerprint list:
SHA-256: 7A6B9841 355B1127 E5639A9D 7040D81C F395D382 884376C2 31829C63 6FCF1B80
SHA-512: 04A49A60 A1645479 ED0B3CE9 AE32E156 E9768CC2 0D4EF393 814162BE BFA6FAF5 6C520769 C654467F 6B61EBD4 4A5A5C93 9DF81B7D AA468A50 2DD7FFF3 F637A49C
Verifying the fingerprint list:
Save fingerprint list, from the first plus to the last plus, to a text file called fingerprints.txt
Next save my key to a file called dcc4e.asc and my signature to a file called fingerprints.txt.asc
In terminal or command line run:
gpg --import dcc4e.asc gpg --verify fingerprints.txt.asc 
You should see:
Good signature from "dcc4e " 
GPG examples for verifying Bitcoin clients:
Verifying Bitcoin-Qt:
First download, import and check Gavin's key:
Download his key at bitcoin.org/gavinandresen.asc
In terminal or command line run:
gpg --import gavinandresen.asc gpg --fingerprint 
Check that the fingerprint for Gavin's key matches 01CD F462 7A3B 88AA E4A5 71C8 7588 242F BE38 D3A8.
Then download the wallet software and signature.
Verify the signature:
gpg --verify SHA256SUMS.asc 
You should see:
gpg: Good signature from "Gavin Andresen (CODE SIGNING KEY) " 
The signature for Bitcoin-Qt signs the hash values. So we must compute the hash of the specific downloaded software manually. This example is using the linux version.
gpg --print-md SHA256 bitcoin-0.8.6-linux.tar.gz 
Check that the output matches the associated hash value in SHA256SUMS.asc
Verifying Electrum:
First download, import and check ThomasV's key:
This key can be found at a keyserver.
gpg --keyserver pool.sks-keyservers.net --recv-keys 7F9470E6 gpg --fingerprint 
Check the fingerprint.
Download Electrum and the signature.
Verify the signature:
gpg --verify Electrum-1.9.6.zip.asc 
You should see:
gpg: Good signature from "ThomasV " 
For this example you do not need to manually compute any hash values because the signature is signing the downloaded file directly instead of signing a list of hashes.
submitted by dcc4e to Bitcoin [link] [comments]

Clearing up some misconceptions about full nodes | Chris Belcher | Feb 10 2016

Chris Belcher on Feb 10 2016:
I've been asked to post this to this mailing list too. It's time to
clear up some misconceptions floating around about full nodes.
=== Myth: There are only about 5500 full nodes worldwide ===
This number comes from this and similar sites: https://bitnodes.21.co/
and it measured by trying to probe every nodes on their open ports.
Problem is, not all nodes actually have open ports that can be probed.
Either because they are behind firewalls or because their users have
configured them to not listen for connections.
Nobody knows how many full nodes there are, since many people don't know
how to forward ports behind a firewall, and bandwidth can be costly, its
quite likely that the number of nodes with closed ports is at least
another several thousand.
Nodes with open ports are able to upload blocks to new full nodes. In
all other ways they are the same as nodes with closed ports. But because
open-port-nodes can be measured and closed-port-nodes cannot, some
members of the bitcoin community have been mistaken into believing that
open-port-nodes are that matters.
=== Myth: This number of nodes matters and/or is too low. ===
Nodes with open ports are useful to the bitcoin network because they
help bootstrap new nodes by uploading historical blocks, they are a
measure of bandwidth capacity. Right now there is no shortage of
bandwidth capacity, and if there was it could be easily added by renting
cloud servers.
The problem is not bandwidth or connections, but trust, security and
privacy. Let me explain.
Full nodes are able to check that all of bitcoin's rules are being
followed. Rules like following the inflation schedule, no double
spending, no spending of coins that don't belong to the holder of the
private key and all the other rules required to make bitcoin work (e.g.
difficulty)
Full nodes are what make bitcoin trustless. No longer do you have to
trust a financial institution like a bank or paypal, you can simply run
software on your own computer. To put simply, the only node that matters
is the one you use.
=== Myth: There is no incentive to run nodes, the network relies on
altruism ===
It is very much in the individual bitcoin's users rational self interest
to run a full node and use it as their wallet.
Using a full node as your wallet is the only way to know for sure that
none of bitcoin's rules have been broken. Rules like no coins were spent
not belonging to the owner, that no coins were spent twice, that no
inflation happens outside of the schedule and that all the rules needed
to make the system work are followed (e.g. difficulty.) All other kinds
of wallet involve trusting a third party server.
All these checks done by full nodes also increase the security. There
are many attacks possible against lightweight wallets that do not affect
full node wallets.
This is not just mindless paranoia, there have been real world examples
where full node users were unaffected by turmoil in the rest of the
bitcoin ecosystem. The 4th July 2015 accidental chain fork effected many
kinds of wallets. Here is the wiki page on this event
https://en.bitcoin.it/wiki/July_2015_chain_forks#Wallet_Advice
Notice how updated node software was completely unaffected by the fork.
All other wallets required either extra confirmations or checking that
the third-party institution was running the correct version.
Full nodes wallets are also currently the most private way to use
Bitcoin, with nobody else learning which bitcoin addresses belong to
you. All other lightweight wallets leak information about which
addresses are yours because they must query third-party servers. The
Electrum servers will know which addresses belong to you and can link
them together. Despite bloom filtering, lightweight wallets based on
BitcoinJ do not provide much privacy against nodes who connected
directly to the wallet or wiretappers.
For many use cases, such privacy may not be required. But an important
reason to run a full node and use it as a wallet is to get the full
privacy benefits.
=== Myth: I can just set up a node on a cloud server instance and leave
it ===
To get the benefits of running a full node, you must use it as your
wallet, preferably on hardware you control.
Most people who do this do not use a full node as their wallet.
Unfortunately because Bitcoin has a similar name to Bittorrent, some
people believe that upload capacity is the most important thing for a
healthy network. As I've explained above: bandwidth and connections are
not a problem today, trust, security and privacy are.
=== Myth: Running a full node is not recommended, most people should use
a lightweight client ===
This was common advice in 2012, but since then the full node software
has vastly improved in terms of user experience.
If you cannot spare the disk space to store the blockchain, you can
enable pruning as in:
https://bitcoin.org/en/release/v0.11.0#block-file-pruning. In Bitcoin
Core 0.12, pruning being enabled will leave the wallet enabled.
Altogether this should require less than 1.5GB of hard disk space.
If you cannot spare the bandwidth to upload blocks to other nodes, there
are number of options to reduce or eliminate the bandwidth requirement
found in https://bitcoin.org/en/full-node#reduce-traffic . These include
limiting connections, bandwidth targetting and disabling listening.
Bitcoin Core 0.12 has the new option -blocksonly, where the node will
not download unconfirmed transaction and only download new blocks. This
more than halves the bandwidth usage at the expense of not seeing
unconfirmed transactions.
Synchronizing the blockchain for a new node has improved since 2012 too.
Features like headers-first
(https://bitcoin.org/en/release/v0.10.0#faster-synchronization) and
libsecp256k1 have greatly improved the initial synchronization time.
It can be further improved by setting -dbcache=6000 which keeps more of
the UTXO set in memory. It reduces the amount of time reading from disk
and therefore speeds up synchronization. Tests showed that the entire
blockchain can now be synchronized in less than 3 and a half hours
(See
https://github.com/bitcoin/bitcoin/pull/6954#issuecomment-154993958)
Note that you'll need Bitcoin Core 0.12 or later to get all these
efficiency improvements.
=== How to run a full node as your wallet ===
I think every moderate user of bitcoin would benefit by running a full
node and using it as their wallet. There are several ways to do this.
(https://bitcoinarmory.com/) or JoinMarket
(https://github.com/AdamISZ/JMBinary/#jmbinary)
Multibit connecting only to your node running at home, Electrum
connecting only to your own Electrum server)
So what are you waiting for? The benefits are many, the downsides are
not that bad. The more people do this, the more robust and healthy the
bitcoin ecosystem is.
original: http://lists.linuxfoundation.org/pipermail/bitcoin-dev/2016-February/012435.html
submitted by dev_list_bot to bitcoin_devlist [link] [comments]

wallet files

can I open a multibit wallet file in the bitcoin-qt client? Is it some kind of standard, or would that break things?
submitted by themann00 to Bitcoin [link] [comments]

Sending before Sync is finished?

I tried to be cautious and deliberate about my foray into bitcoin but still running into stumbling blocks. The Qt client has been running for several hours and is barely finished synchronizing. I've already sent money into the wallet address provided by the client but now I'm worried my 120gb HD won't have enough space to hold the ridiculously huge blockchain.
Is there a way to bail out of the Qt client and use something that's a little more responsive (such as multibit) AND keep my money without waiting for the blockchain, or am I tied for the time being?
I'm still not clear what the 'wallet' is exactly when it exists as a file. Is it the address or is it a snapshot of your wallet at a given time? If it's the latter, wouldn't a one-time backup be sufficient? So confused. And what's the compatibility of wallets between programs?
submitted by aceticacidz to BitcoinBeginners [link] [comments]

Question about Multibit Wallet & Java

I uninstalled Java on my computer because of the vulnerabilities stories that have been circulating around it, and because of an annoying pop-up to update it every time I ran my computer.
Anyways, now my Multibit wallet client wont open, and it asks me every time to update to Java [OK] or [Cancel]
Why does Multibit need Java to run? I'm waiting for the blockchain on my Bitcoin.qt wallet to update now so I can import my wallets.dat files. I used Multibit because I preferred their interface over the BTC.qt, but is it safe to use knowing it needs Java?
submitted by Chinxcore to Bitcoin [link] [comments]

Sending and receiving Mastercoins for the novice

I'm hoping someone will be able to assist a novice with some basic questions regarding sending and receiving Mastercoins. My questions:
1) To send MSC I want to use JR's Mastercoin Advisor. What is the "data address"?
(i) Is the "data address" a new, unique address generated by the Advisor for each transaction according to what you input?
(ii) Does the unique address include the information on what is sent (TMSC or MSC) and the amount sent so that this does not have to be specified when sending the transaction from the Bitcoin-QT client -- i.e., that information - amount and type -- is included in the data address?
2) Once you have the data address, is that all you need from the Advisor? I.E., you set up a transaction manually on Bitcoin-QT, sending 3x 0.00006 BTC to each address - Exodus, MSC recipient and Data addresses?
3) Is a miner's fee required? If so, is it 0.0001 BTC? To which address do you add the miner's fee?
4) Are MSCs sent the same way as BTCs? Bitcoin-QT send the entire amount of your MSCs from the address holding the MSCs and then sends back the change to a different address in your wallet? So if I have 1000 MSC on the address and send 100 to the recipient, I receive 900 back at a different address in my wallet with a different private key? Or are they sent back to the same address? How will I know which address the change is received at?
5) When sending Mastercoins from the address holding the MSC, do I need to have sufficient Bitcoins at the same address? In other words, I need to co-mingle BTCs and MSCs in the same address? How does the wallet tell them apart?
6) Finally, if I received the MSCs from the Exodus Address in a Bitcoin client that does not support sending to multiple addresses (in this case Multibit) can I simply import the compressed private key to the Bitcoin-QT client to perform the transaction? Are there any concerns about having the same data in two clients?
That's a lot of questions. If anyone can answer any of them (you don't have to tackle them all :) if that too much trouble, I'd really appreciate it.
Many thanks.
submitted by Yamanote to mastercoin [link] [comments]

How secure/trustworthy are alternative clients?

I've been using the Satoshi client on OSX for a couple years now for my main wallet, aka long term storage. However lately, it's become an enormous pain in the ass. Any time I have to close the client, when I reopen it there's some "corruption" somewhere and I have to re-index the entire blockchain, which takes 2-3 days.
I'm getting tired of it, and help does not seem to be on the way. That said, I'm wondering how safe or trustworthy alternative clients are. I know Armory requires a functional Qt client, so that' out, but I Multibit and Electrum are recommended by Bitcoin.org.
Other than not being a "full node" and having to trust the blockchain I'm connecting too, are there any other security concerns with running multibit? Can I install and copy my wallet.dat file with it? (I know from some usage on Linux that Electrum works differently)
submitted by BuckleChuckle to Bitcoin [link] [comments]

Question about bitcoin wallet clients...

I'm using the Bitcoin QT client right now. The one complaint I have about it is organizing addresses. There's just the one window, and only the options to sort addresses by the label or address.
I'd like to have a couple of different wallets for a few different purposes.
One for a spending account for personal purchases. Another one to accept payments. A cold-storage wallet. Maybe something else, as well.
The wiki is somewhat sparse on details and comparisons about the various bitcoin clients. https://en.bitcoin.it/wiki/Wallet
But, it feels like the options I have are either Multibit or Armory. Can someone give a quick review or comparison?
submitted by Morichalion to Bitcoin [link] [comments]

Bitcoin: Client-QT Wallet Update Version 0.11.0 Bitcoin Core + TOR - FAQ DARKNET Funktion & send save BTC 4NOOB 2017 sk2eu ✔✔✔ Bitcoin.pl Poradnik #2 : Instalacja klienta Multibit Bitcoin-qt Wallet Update 0.8.3 Bitcoin-QT Wallet Update

Bitcoin Core ist ein gemeinschaftliches, freies Software-Projekt, veröffentlicht unter der MIT-Lizenz. Release-Signaturen überprüfen Download über Torrent Quelltext Versionshistorie anzeigen. Bitcoin Core Release Signierschlüssel v0.8.6 - 0.9.2.1 v0.9.3 - 0.10.2 v0.11.0+ Oder wählen Sie Ihr Betriebssystem . Windows exe - zip. Mac OS X dmg - tar.gz. Linux (tgz) 64 bit. ARM Linux 64 bit ... Bitcoin-Qt-client: der Einfache Weg, um mit einer Brieftasche.dat nicht in seinem Standardverzeichnis ist/wenn es fragt nach meinem Passwort überhaupt? Es muss nicht sein genannt "wallet.dat", richtig? Das wäre zu offensichtlich. Können Sie nennen es etwas, mit jeder Erweiterung? Bitcoin-Qt ist eben nicht so trivial, um mich zu bedienen, da die triviale Möglichkeit wäre ein option File ... Run dumpprivkey [Receiving Bitcoin Address] for each receiving address to be migrated to MultiBit. There may be hidden private change addresses in Bitcoin-Qt which don't show up in the receive tab. Run listaddressgroupings. Copy the results of dumprivkey for each address (which are the corresponding private keys). Start the Multibit client and ... I don't even know if I have one yet, becuause all I have done is downloaded a bitcoin client (Multibit). wallet address multibit. share improve this question follow asked Feb 21 '13 at 22:32. 999666blue 999666blue. 61 1 1 gold badge 1 1 silver badge 2 2 bronze badges. add a comment 1 Answer Active Oldest Votes. 6. Click 'Receiving', then look for an address. share improve this answer ... 1. Bitcoin-Qt. We list Bitcoin-Qt first because it is the official Bitcoin client which acts as the backbone of Bitcoin's network security. The below clients depend on Bitcoin-Qt, so you will have to install it first to use Multibit or Armory. The installation with the below commands is very easy. But once you started it for the first time, it ...

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Bitcoin: Client-QT Wallet Update Version 0.11.0

In this video Jason explains the new update that rolls out on the bitcoin-qt client and what parts of the client were altered and positively effected. What i... Months ago, I tried to learn a bit about Bitcoin, tried a few programs, mutlibit [1] is only one that I could barely accept. Some are way too complicated. Th... Bitcoin.pl Poradnik #2 : Instalacja klienta Multibit ----- Nasz poradnik w prosty i zrozumiały sposób przedstawi Ci wszystkie kroki potrzebne do zainstalowania klienta transakcji Multibit, oraz ... Bitcoin.pl Poradnik #2 : Instalacja klienta Multibit - Duration: 5 minutes, 56 seconds. Bitcoin.pl . 6 years ago; 8,956 views; Bitcoin.pl Poradnik #2 : Instalacja klienta Multibit-----Nasz ... Nur mit diesen Client (bitcoin-qt.exe) und TOR bist du recht sicher. Alles andere kann man ja ziemlich leicht im Netz sehen. Alles andere kann man ja ziemlich leicht im Netz sehen. Wo kauf ich ...

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