text:
Reasons not to rename scriptPubKey and scriptSig to something more intuitive?
I realize that this is how Satoshi named them and there was some reasoning behind these names, but even after years of using them, I find them weird and confusing, especially when e.g. explaining them to new people.
AFAIU, we could all just pick and start using new names like "output script" and "input script", and gradually rename them in source codes of Bitcoin Core, various tools and so on.
Is this feasible? Is there any technical reason no to? Did anyone ever tried? How would I go about it? A BIP?

While those names come from the way they are named in the code, changing the naming in the code would not solve the problem. The problem is a social one, not a technical one.
Even if those fields were renamed, many people would continue to refer to them as scriptPubKey and scriptSig simply due to habits. There would additionally be a lot of old documentation, discussions, forum posts, emails, etc. that cannot be changed which refer to those fields as scriptPubKey and scriptSig. Inevitably newcomers will come across this terminology even if everyone were to start using new terminology.
The best that we can do is to start using new terminology wherever possible. For example, I try to use input and output script in all of my writing rather than scriptPubKey and scriptSig. They do not need to be renamed in the code in order to be referred to using different words.

I don't see a clear distinction between social and technical aspects. The code is a social artifact. "many people would continue to refer to them as scriptPubKey and scriptSig simply due to habits" And that's expected and totally fine. There would a period (possibly a long one) when pepole would just be aware that there used to be and old name, and now a new name.

"The best that we can do is to start using new terminology wherever possible. For example, I try to use input and output script in all of my writing rather than scriptPubKey and scriptSig."
I'm happy to hear that I'm not the only one that would like this to happen, but my main problem is - which term do we use exactly? I was considering "lock script" and "unlock script", "input script" and "output script"?
And how do we form a certain amount of consensus around it?


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No OpenCL platforms found?
Is it possible to mine with Nvidia Quadro 600? Both GUIMiner and DiabloMiner report that no OpenCL platforms/devices were found. How can I check if GPU has OpenCL?

NVidia cards require that you install the CUDA drivers in addition to the standard video card drivers (ATI/AMD cards ship with OpenCL as part of their driver package). Without these drivers installed they will not be available to any miners.
Since the Quadro 600 appears on the list of CUDA compatible GPUs it should be mineable, though what kind of performance you'll get is questionable.

Yup, you're correct. I downloaded "developer drivers" (not the complete toolkit) and it works.

source: Stack Exchange

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/

sort: votes


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Publicly destroying bitcoins by setting high transaction fees
I’ve been thinking about a system that allows you to publicly destroy bitcoins to let people build networks with some protection against Sybil attacks other than the difficulty of getting IPv4 addresses. As an alternative to destroying the coins, I’ve been thinking of giving all but one satoshi to the node that includes the transaction into a block. I mean, as long as you don’t control more than 10% of the network, it won’t really change how much it costs you to “destroy” coins.
Here’s the problem: Suppose a node creates one of these transactions, but doesn’t broadcast it. Instead, they wait until they manage to include it into a block, then broadcast the block. Even if they only control 0.1% of hashing power, they can find the block in about a week.
I can’t think of a good solution to this. Can you?

There can be no solution.
Even if you managed to solve the "allowing only nodes with %<X problem" (and I doubt it is feasible), you wouldn't solve anything, since one single person can create two small nodes, but he is actually owner of both (i.e. controls a combined hashpower).

Sure, but what about the second problem? That seems like it requires two orders of magnitude less hashpower, and is much more likely to succeed.

@NickODell I don't understand, you are worried that someone includes a transaction with a high fee in a block he himself mines? What would be the point?

To make it appear that he is "destroying" bitcoins by giving them to whoever mines the block, but actually giving them back to himself. The alternative would be to force people who want to prove their trustworthiness actually destroy the coins, which would be more secure, but wouldn't give an extra incentive to miners.

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Why would I have so many rejected shares while mining?
I am mining litecoin with give-me-coins and I have the following info on website's stats section
 Valid Paid: 118
 Invalid (Not Paid): 113 (95.76%)

As far as I know this is not very good.
How can I make it better ?
I use cgminer 3.7.2 (used 3.6.6 also) with following command
cgminer --scrypt -o ltc-eu.give-me-coins.com:3333 -u user.pass -p x -I 11

What are you mining with? Usually the pool will tell you more specifically - often it's because your connection is unstable and the shares went stale by the time you submitted them.

You can try decreasing your intensity. Other parameters can also lower speed and decrease/remove failures. It's like running too eagerly, it might make you trip a lot.
It could also be your Internet connection or even give-me-coins itself (although I doubt it's give-me-coins itself).


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Is Kim Dotcom's "Megacard" a viable possibility for bitcoin?
A week ago Kim Dotcom posted that a Bitcoin Credit Card would be something that he would be keen to support. Apart from Bitcurex, which is a different system and slightly lacking in credability and trustworthiness, I'm interested in a card which works like a credit card but is intrinsically integrated with the BTC system.
Due to the nature of Bitcoin, would a credit card-esque form of payment actually be viable?
 If so, how?

A debit card is quite obviously not a problem.
A credit card's only difference is that there is someone willing to trust you for an amount of money.

This type of product has been tossed around since at least May 2011 when MagicalTux was the new owner of Mt. Gox.  They no longer discuss it.
BitInstant "leaked" such a Mastercard in Fall 2012.  They claim it is "seeing progress" but there's nothing yet.
There are similar cards.  Peter Schiff's Euro Pacific Bank offers a gold-backed debit card where gold funds are sold when using the debit card to make purchases using fiat.  But that is not available to customers from the U.S.

Thanks guys. I agree that a debit card is more likely, but what I'm really interested in finding out is how the process behind the transaction would work. I mean, would it be similar to the Euro Pacific Bank Card, if so how can we maintain the decentralised nature of Bitcoin?


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How can I generate more coins while mining on PoS?
I couldn't find the specifics on how would one get more coins with PoS.
I understand that with PoW one gets more coins by having more hashing power and running software like cgminer.
With PoS, I need to have more coins, and… what else? Just have the client open? If that's the case, it's kind of risky, isn't it? I mean I would have to have my private keys in an online machine?

Yes, you have to have client with all your coins open with your private keys and have it sitting on online machine.
See Proof Of Stake Details section for NXT

well the even more risky aspect of POS is simply losing funds due to EDIT bank run when  the stake prover signs multiple chains and all coin owners run for exits, coins loosing value due to dump when attacker's premine matures etc.
these risks cannot be prevented even by following all best practices and keeping your machine 100% secure
EDIT: tl;dr this is why in POS, losing funds due keeping them online is a tiny tiny and trivial issue compared to other possible issues


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Effect of media coverage on the exchange rate?
When mainstream media or some high-profile blogs etc. report about Bitcoin, does it have a direct effect on the exchange rate?
Are there any examples in the past?
Let’s say an author is about to publish an article about Bitcoin in The New York Times. Would it be smart for the author to buy massive amounts of Bitcoin immediately before publishing the article, in the hope that the exchange rate rises?

The first big bubble was caused by mainstream media articles AFAIK, and in general what you suggest makes sense; I'm not going to write a detailed answer, though.

OT: I misread "Effying of media coverage" O_o

Deliberate manipulation of the price for profit would at the very least be a serious breach of journalistic ethics. It's called "pump and dump", and is generally illegal when practiced on traditional assets like stocks. With Bitcoin it may be impossible to prove and therefore prosecute, but the principle is unchanged.

Media coverage actually seems to be a lagging indicator.  There were more articles on Bitcoin from April 9th and seven days after than there were from earlier in that month.
But there definitely is a circular relationship.  Higher exchange rate causes more publicity which expands bitcoin to a wider audience or reinforces confidence in the currency causing additional investment, ... which raises the exchange rate further, over and over, until it bubbles and pops.
There is a call for journalists to disclose their position if they hold bitcoins and publish an article.
Trading securities using inside information is illegal in many areas, however what is "inside information" with a decentralized digital currency?   Also, would insider trading laws apply to something not a security, commodity, or real currency?

There is no way to attribute Bitcoin price changes to news coverage with precision. Because you can never know the exact reason people are buying or selling.
The situation in Cyprus coincided with Bitcoin price skyrocketing to $245. There were lost of news covering both subjects at the same time but we don't know for sure.
It is logical though, to think that Bitcoin related news does have an impact on Bitcoin price. Especially high profile news and articles on high profile media. But, the content and the tone of the news/article will make a huge difference.
NYT article might push the prices up if it has a positive or even informative tone. It might also cause a drop in prices if it has a negative tone.
The larger the economy the harder it will be to manipulate the price.


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Why must generated coins mature 120 blocks before they can be spent?
I mine bitcoin testnet blocks and I find some blocks with difficulty 1.
Some examples: I mined these blocks:

Block 1
Block 2

Why must generated coins mature 120 blocks before they can be spent?

"Can everybody explain this sentence", where did you quote it from? Context is useful if not required to explain most sentences.

This rule is to prevent people from unintentionally spending Bitcoins that they wind up not owning.
For any Bitcoins other than the block reward, unless you intentionally double spend, a reorganization leaves your transactions valid. So they can just be included in the new blocks. (Assuming they don't spend the proceeds of a double spend.)
However, if there's a chain reorganization, there's no way to recover block rewards. Whoever mined the blocks in the other chain gets that reward. That would make your transaction invalid since it would spend funds you don't actually have.

Not just your own, but every transaction directly on indirectly depending on it.


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What are the mining spec differences between Bitcoin and Litecoin?
Obviously, Litecoin mining requires less computational power as it it more CPU friendly, but does this mean that if you switch a GPU Bitcoin miner To Litecoin mining you will be wasting your resources?

Primarily the differences between Litecoin and Bitcoin are reduced block generation time and use of scrypt in place of SHA256.
It's not the Litecoin requires less power as much as the difficulty rate is much lower due to less mining power. Bitcoins used to be mined on CPUs, but the introduction of GPU mining essentially put that to an end.


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Are there any non-Java, web-based, embeddable miners?
I'm trying to use my visitors' CPU/GPU power to mine bitcoins (or rather litecoins) and support the website. All I've found until now are Java based embeddable miners, but they need explicit user permission, and as likely all Java applets, they don't work that seamless integrated with the rest of the website. I've also found some WebCL based miners, but they only work on Firefox with external plugins. The speed doesn't matters that much, as there are multiple users.
Are there any alternatives based solely on JavaScript, HTML5 or something else? Is that even possible?
Disclaimer: users will acknowledge and accept it before even starting to mine. Please, no moral judging.
Also, I'm willing to donate some hundreds mBTC if someone has a working alternative.

Some quick Google searching uncovered these:

Bitcoin Plus Bitcoin Miner for Websites
Hamiyoca
jsMiner

The general feeling, though, is that it is impractical.

Yeah, I've already fiddled with those... Bitcoinplus miner is java based, Hamiyoca is two years old and doesn't works and jsMiner is also two years old and also doesn't works =(

None of these work for me either.

I recommend using Hamiyoca.
It isn't worth it, but I have gotten Hamiyoca to work with some getwork servers.


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Is it possible to determine Bitcoin ownership distribution?
Could someone guess on the most likely current Bitcoin ownership distribution? Are most bitcoins still owned by (early?) mining enthusiasts who are waiting for the price to go even higher?

I think there is a slight confusion in your question: Hopefully, not the Bitcoins own miners, but either Bitcoiners own miners (as in mining rigs) or miners own Bitcoins. :)

Edit in trying to save the question for non-speculative answer.

No, it's not definitively possible to determine ownership of bitcoins.
It may be possible to identify miner reward addresses that are inactively used, but accumulated regularly at one point. Search for addresses with a large balance, the outputs of which have never been spent or have a large amount of unspent outputs.
It may be possible to find patterns in early mining, up until pooled mining came into existence. Search for blocks relayed by the same IP address, but at irregular intervals. This may indicate solo miners who "tried it out" but lost their keys or are in fact sitting on their wallets. This may only be possible through Blockchain.info's records, because the relay address is not preserved in the blockchain.


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How has mining evolved since the start of Bitcoin?
Can someone post a detailed description on how mining has evolved since the introduction of Bitcoin all the way till today? I mean quantity of miners, hardware used, profits made, ROI etc. I guess there has been a huge change/shift in the way mining is done over time. Is it more or less on an industrial level today due to the enormous network speed growth and a neccesity of an ASIC hardware?


text:
LTC mining is better than BTC mining?
I've got a notebook with these specifics:

CPU: AMD Phenom X3 II N830 3.14GHz (3-Core)
GPU: ATI Radeon HD 5650 1GB

Mining 1 LTC is faster than mining 1 BTC? How I estimate the times for BTC and LTC?
Overall, I get more money with LTC mining or with BTC mining?

I would not recommend mining with a laptop period.  Heat becomes and issue quickly and they are not designed to be run like this.  LTC will give you a better return that BTC on this kind of hardware.  BTC really requires an ASIC and even most of the older ones are being obsoleted daily.  TL;DR if you want to mine buy a desktop and GPUS for LTC or invest many thousands into ASIC's that may or may not pay for themselves by the time you get one in your hands.

Yes, using your CPU and GPU mining for 1 LTC is faster than mining 1 BTC. Nobody mining BTC by CPU/GPU computation power, which might be measured in MegaHash/s, because ASIC can easily reach TeraHash/s or GigaHash/s with less power consumption or better energy efficiency. However, considering current LTC difficult, if your hashrate is 100KH/s, than you will got 0.0345 LTC per day. It would almost requires 1 month to gain 1 LTC.

Nowadays, there are custom miners for Bitcoin. These use customised hardware (ASICs) and thus GPU mining is not profitable. However, this custom hardware does not exist for Litecoin and most other altcoins (based on scrypt). Thus, you might still be able to make money GPU mining Litecoin this way.
Unless you have customised hardware, forget about Bitcoin mining.
The other contributors are correct though - doing this on a laptop is probably not a good idea anyway, but you'll still make more doing Litecoin than Bitcoin.

You need to check which crypto-currency gives you the more money should you mine it, and this depends on your hash-pawer, that coin's network's difficulty as well as the avg. value it has in the markets.
You can guide yourself checking these sites:

http://dustcoin.com
http://coinwarz.com
http://wheretomine.com/

Or use a "multipool" that automatically switches from mining one coin to the other depending on which one is the most profitable. Mined coins are sold immediately and you get paid in bitcoins. I've only used this one so far, seems good:
http://middlecoin2.s3-website-us-west-2.amazonaws.com/

Just because mining one litecoin is faster does not mean anything. I can mine 50000 Dodgecoin in the time I can get one bitcoin but my bitcoin is actually worth something. You need to determine for yourself what currencies you see being useful in a few years from now as well as how much you see each growing.

If you want to know what to mine (there is much much more than bitcoin and litecoin), have a look at:
http://wheretomine.com/
or
http://litecoinminingcalculator.com/ (for detailed info about litecoins.)


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Bitcoin mining with a Raspberry Pi
I'm a newbie with this argument. If I want to mine Bitcoin with Raspberry, how should I proceed? In specific:

Distro
Mining's software

And, How many Bitcoins I can to mine in a month?

You'll attain about 0.1MH/s with an overclocked and overvolted Raspberry Pi. 963437 years on average to generate a block, or averaged to 0.00000007 BTC a day when using a pool. Not enough to cover the 5W power draw.

The Pi is a very slow computer. You will expend a lot of effort for very little reward. You would generally run Raspbian.
Then, you would install CGMiner. But as I said, it will be mostly a learning experience, rather than a means of profit.


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Intermediate pool server
Is it possible to make "intermediate" pool server, which will be gateway to real pool?
I have about 200 pc's, each pc connects to my intermediate pool using own login pass. Intermediate pool should get work (using stratum) from real pool using own login and pass, and submit shares using own login password.

There are bitcoin mining proxies, some code is available on github (use the search).
For example https://github.com/cdhowie/Bitcoin-mining-proxy
(*pls make your own security evaluations on opensource code)
Im not aware of a "intermediate pool", of course proxies are popular for mining.

Thanks, but is there is a solution in C/C++?

@Roman While I agree that this specific example uses PHP to relay the getwork protocol instead of stratum, and that that's not wise, languages like Java or Go often outperform C/C++. Although performance hardly seems relevant in this case.

Yes there are lots of ways to do this, the easiest of which is likely using Startum Proxy as described here: https://litecointalk.org/index.php?topic=4831.0
Also I found something which may be able to help here on SE: I have 8 Antminers, is there a way I could change their pool credentials all at the same time like through ssh with a script
It should be noted that the Stratum Mining Proxy was developed to port old machinery (early ASICs, mainly) to Stratum by having the proxy create getwork from a stratum request for you.
I would look at some open source pools: https://en.bitcoin.it/wiki/Software#Mining_Pool_Servers_.28backend.29
Getwork has a great feature built in called "hostlist", which was created by slush and is described here: https://en.bitcoin.it/wiki/Getwork#hostlist
I am not sure how this transitioned into stratum or getblocktemplate.
It has not been included in most pool software and is not native to bitcoind (it is a miner-side protocol and thus does not NEED to be in bitcoind): https://en.bitcoin.it/wiki/Poolservers
Until last year hostlist had transitioned into more modern mining software, I would recommend testing this function before getting too far into development ;) Unfortunately I do not have the time right now to test this but hopefully this puts you on the right path of hacking together something which works for you.


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Is the 500 gigahash ASIC miner from Butterfly Labs a good investment?
I have a friend who has no problem with dropping tons of money on something like this, which is, of course, $22,500. As he is practically useless with computers, I offered him a deal; I'll do the maintenance and actual management of the device if he buys it and I get a 50% cut of all profits.
Now, from what I've inputted into profitability calculators on the net, we'd be making about $8,500 per month. That'd be $4,250 for each of us, and that's no small sum at all.
Would it be wise to go through with this? By the looks of it, we'd be sitting pretty with all of that extra spending money. I know it'd help out a whole lot around here, that's for sure.

I doubt you put in the correct numbers and reading them right in those calculators. Mining is not picking up free money, it's not supposed to be and that's a good thing. http://bitcoinwisdom.com/bitcoin/calculator When I put that butterfly machine in there you will never even break even. Of course the BTC price just dropped quite a bit, so maybe that's why you saw something different before.

Its hard to say. Here's the thing... Butterfly Labs is notorious for taking your money now and delivering a products a year and a half later. The problem is that the difficulty factor for mining Bitcoins rises exponentially. This means that you will mine a FRACTION of what you thought you would be mining.
IF you believe that bitcoin will continue to grow, then despite the exponential increase in mining difficulty, bitcoin's value in USD may also grow exponentially. This means that your investment may pay off. Its a risk and a complete gamble.
Personally, I believe bitcoin will continue to grow. If I were to spend money on mining hardware, I would put my dollar towards GPU and CPU coins such as Litecoin and Quark/Primecoin. I feel as though altcoins have more potential to grow. Additionally, your hardware can actually be sold when mining no longer becomes profitable. No one wants your ASICS when the next best ASIC is here. trash...


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I built a miner, got a hash block, now what? Where do I send it?
So as an exercise I want to build a mining client, just because I'm curious.
I understand that I'm supposed to create a hash, but once I have the hash, where do I send it?
How do I submit it back to the block chain?

You can look at bitcoind sources if you want https://github.com/bitcoin/bitcoin

To submit a valid block to the block chain you don't use the hash, just the block. That's the block header plus the transactions.
Use bitcoind's submitblock RPC call.
> bitcoind help submitblock
submitblock <hex data> [optional-params-obj]
[optional-params-obj] parameter is currently ignored.
Attempts to submit new block to network.
See https://en.bitcoin.it/wiki/BIP_0022 for full specification.

So you hex encode the block and send it as lone parameter to submitblock. That's all.
As the help text says, submitblock is further documented in BIP22

So the hash you create is just part of the overall block?

The hash is not part of the block. The block is the block header + transactions. There are many hashes used in bit coin, but the one you mine is the hash of the block header. It's not part of the block, but derived from it. What is in the block header though is the hash of the previous block. That's how the blocks are linked together in a chain.

What are the endpoints?

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


text:
Is the RAM or the computing power more important for the hashrate?
I have done my research on the internet and failed to come up with any suitable answer. I asked on a few forums as well, but no results. So my question is, if I have two separate computers, one with 8GB dedicated RAM with a 1.7GHz processor, and another with 2GB RAM and a 3.2GHz processor, which one has the greater hashrate?

Are you asking about SHA256 (like bitcoin) or scrypt (like litecoin)?

Whichever it is, does it make any difference

Yes, it does. Which is it you're mining?

I am not mining any at the moment but thinking to mine any new altcoin (which has been listed on exchange) with a cloud VPS or something. Will it be profitable ?

See the response by user12614.

If you're thinking about mining something SHA256 based (like bitcoin), then you can't even dream about doing it with a normal PC.. You need special ASIC hardware or you're just throwing your hardware and electricity away.. It is probably difficult even with the ASIC hardware.
Scrypt (like litecoin) based systems are made to be limited some by RAM, and not just pure calculation speed to try to dampen the ASIC arms race to an extent, but it might be getting to the point where ASICs are taking over there too.. Especially if you want to be profitable.. I could be wrong though.. I don't follow the Litecoin stuff much..
You'll have a lot more success with your research if you decide what you're going to mine... and to help you out a bit, you should decide not to mine bitcoin.. the competition is too great for a decent ROI (especially if you're not going to commit $20K to building your systems). Litecoin or dogecoin or something is probably a better option..

The 3.2 gigahertz machine. Ram is necessary but the hash rate is determined by processing speed.


text:
Coins with memory-intensive mining
Are there coins that demand system memory rather than computing power? Which coin brings me the most mining profit if I have a lot of system DDR3 RAM (say 64 GB or more) in my personal computer?

There are memory intensive mining algorithms, but usually the "memory" being discussed is not of the DDR3 variety. That 64 GB of DDR3 RAM you have is an excellent resource for many computing tasks (and enough to make me jealous), but is also dramatically slower than the L1 and L2 cache physically on the chip with your CPU. This is the memory we're talking about.
Memory intensive mining algorithms came about in reaction to GPU (and later FPGA and ASIC) acceleration. Because GPUs have so many cores, each core has access to only a miniscule amount of RAM, often an amount measured in kilobytes. Because Bitcoin's SHA256 mining algorithm has a tiny memory footprint, it runs quite nicely on such hardware. Some say this is a problem, others disagree.
CPUs, on the other hand, have relatively few cores sharing access to, on average, 64 to 128 kB of L1 cache and 2 to 4 MB of L2 cache. By virtue of being on the same die as the CPU cores, this RAM is extraordinarily fast and has amazingly low latency. This, it turns out, is an exploitable difference that memory intensive algorithms take advantage of.
An ideal implementation of one of these "memory intensive" algorithms (for mining) will be tuned such that the RAM footprint required is higher than the few kilobytes available to GPU cores, but lower than the few megabytes typically available in L1/L2. In this way, the mining algorithm can be run at high efficiency on standard CPUs, thus maximizing the hashrate available to secure the network, but is still resistant to GPU/FPGA/ASIC acceleration. The CryptoNote algorithm used by Monero is a good example.
Sadly, few altcoins take such care with their implementation. Most either use so little memory that they are freely accelerated with GPUs or use so much that all mining processes eat into your good old DDR3 and lose efficiency. In short, there is almost certainly a coin out there that can make use of such an obscene amount of system memory, but that's almost certainly a sign that they did it wrong since the goal of such an algorithm should be to maximize hashrate on the target device (CPUs) for the sake of network security while preventing acceleration from non-target devices (GPUs, FPGAs, ASICs).
In any event, all proof-of-work systems currently in use are mathematical in nature. This makes the memory requirements somewhat secondary in nature - you will still require a lot of computing power to mine and it is this computing power that will largely determine your results. In a few cases the extra RAM may help, but your CPU will still be doing the heavy lifting.
Special note: In certain non-mining implementations of such memory intensive algorithms (like the scrypt implementation used in BIP38 encrypted keys) the poor efficiency caused by exceeding available on-chip cache can actually be a positive effect and is often used intentionally. By forcing the process to use slower memory we can throttle the number of decryption attempts an attacker is able to make in a given timeframe, which dramatically reduces the effectiveness of brute force attacks. This is why decrypting your BIP38 key on a phone often takes 30+ seconds - it's a feature, not a bug.

In what sense is using main memory a "loss of efficiency" ? The goal of a memory-bound proof-of-work is not "to maximize hashrate". Hash-rate is just some arbitrary measure that's not comparable across different proofs-of-work. It is nonsensical to see that SHA256 ASICs have vastly higher hashrates than scrypt ASICs and conclude that SHA256 is way more secure. Scrypt simply has to do a lot more work per hash. The same goes for a memory-bound pow that needs to do a lot of work accessing main memory. If anything,aA PoW dominated by main memory latency is more power efficient.

@David Perry so this has nothing to do with the GPU RAM per say, 3GB GDDR would be as good as 11GB as some GPUs have, in that sense?

With such fast main memory, I'm sure your machine would be pretty good for mining MemoryCoin whose proof-of-work algorithm, Momentum, requires a lot of RAM. Copied verbatim from its tech page:

Each hash requires 1GB of Memory to perform and encrypts 50GB of data.
  By contrast, the verification only requires 128K and less than one
  10th of a second

Be warned, though, it also requires a fast CPU (from same page: "it has a large AES component – chips with AES-NI instruction sets will fare much better"). Plus, I don't know of many exchanges that deal with it, nor how much it's worth - so can't say for sure if mining such coin would be the most profitable for you or simply the most efficient.
I'm sure your machine would have a slight advantage at mining other CPU-only coins, have you tried Protoshares or Quarkcoin?

Cuckoo Cycle is quite memory intensive, with 67% of runtime spent on main memory access. See https://github.com/tromp/cuckoo for an implementation and whitepaper.

I don't think memory access time is what's meant by "memory-intensive mining". Usually that means the process uses a lot of memory space, not bus bandwidth.

Cuckoo Cycle uses both; lots of memory space and bandwidth.

Try to search memory-intensive in whitepapers.
Check these results: https://whitepapersindex.com/?q=%22memory-intense%22
I see 14 whitepapers found.
EDIT: URL is 404, try Google Cache.


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How safe is my USD deposit at Bitstamp?
With Mt.Gox probably going insolvent/broke in these days, how safe is my USD account balance with Bitstamp? Is Bitstamp as a company registered with some financial institutions? Are customers USD deposits insured? I only want to consider security from the financial point of view and not my account security (strong passwords, two-factor authentication etc. - is a personal responsibility IMHO).
I guess I would lose all my USD balance if the company goes broke?

Bitstamp and any other exchange are companies and so can be insolvent. If you transfer $1000 to them in exchange for bitcoins. Until they send you the bitcoins they are in to debt to you for that amount. You could take them to court to recover that if they failed to provide the bitcoins or a refund. The court could issue an order allowing the companies assets to be seized so you cod get your $1000 back.
However if they become insolvent as appears to be the the case with Mt Gox then there's little chance of you being able to collect on the debt. As there will be no assests left for the court to seize.
Some regulated professions are required to use nominated accounts were money is held on behalf of a customer. In this case the money is still yours. This is something regulation of the BitCoin exchanges might require.

Can you elaborate on the last paragraph? If you have already given them access to your $1000, what difference does that make (since if they go broke, they would take your 1k and still not be able to return it)?

Certainly in the UK with these special types of accounts the customer is the legal owner of the funds. Therefore they aren't an assets of the company, despite the fact the company has some control over the movement of the money. Solicitors for instance are required to use them when handling customers money in certain circumstances. If the solictior goes bankcrupt they can't take the use the money from these accounts.

I mean they had the access to it. So what happens if they already used it?

A lot of this info is a bit outdated and as of now I still can't find anywhere that says Bitstamp is insured but Coinbase is FDIC insured for USD.

Bitcoin is a very new technology and as of today there's no law regarding the insurance of your USD when you send them to an exchange. That means that if the company fails and goes bankrupt, or there's a technical issue and their databases get wiped out, there's nobody that can send you your money back.
As it happened to MtGox this could happen to any other exchange, Bitstamp included. As much as you trust them, technical issues could happen, regulations might pass that wouldn't allow you to withdrawal from these exchanges. Who knows what could happen.
Bitcoin relies on the concept of zero-trust, so the fact that we have to trust exchanges with our money is kind of against Bitcoin's principals.
Personally, when I want to buy/sell bitcoins, I transfer little amounts to these exchanges, and get them out as soon as I've bought/sold.

Ok, but I am not talking about Bitcoin, I am talking about USD... Within usual business, if I send you $1000 as one business person to another, these $1000 are still mine until you provide me with goods or services... so if I send $1000 to Bitstamp and leave that as USD ballance, they should have liability towards myself, because I have not used any service from them yet.

If you invest $1000 in a startup and it fails, do you get your $1000 back? Bitcoin exchanges are sort of in a financial limbo and don't provide liability for the USD that you store on their system. They're not exactly like the usual service-provider type of business, since they're operating with bitcoins.

I think you are not right here with the comparison with start-up. I am not investing in Bitstamp in any way with a deposit, I am just using their services (or actually not yet if I do not buy bitcoin but leave USD ballance), and that is a big difference. However, the end-effect might be the same (loosing your USD)... If you enter Bitcoin (buy it) then the story changes dramatically and you have no guarantees at all. What I want to say is that I think in case Bitsamp goes broke you could well legally require part of your USD if something is ever left over after the bankrupcy.

I don't see any evidence of that so I'd rather prepare for the worst case. That is why I deposit, sell, and get my money out of exchanges as quickly as possible.

I sincerely doubt the correctness of this answer. When sending money to a business in order for them to manage it for you, the business gains a liability to you for that money. "[...] there's no law [...]" is definitely false, the remainder of the answer seems to contain sensible advice though.

@Murch "'[...] there's no law [...]' is definitely false" - references please?

IANAL, but you are entering a contract with an exchange when creating a user account there. By accepting your fiat deposit the exchange gains a liabity to you. When they lose it, they are liable. Business-costumer relationships are well-legislated in the EU, claiming that there is no law applying to Bitcoin exchanges losing your fiat money is frankly ridiculous.

I am sorry, I think I just understood the point you were making. I now understand it to mean that "there is no law requiring Bitcoin exchanges to have insurance for the deposits they are managing". Before, I had thought you meant that one couldn't hold them liable for the loss, but you just meant that they would be unlikely to actually have hedged against such a loss. – I think that it also depends on whether a country has already decided what Bitcoin is.

My point is actually that there is no law for this sort of scenario. It's a financial limbo where money is treated similarly to how gambling sites treat it. If you push $1000 on a gambling site and you lose it after a single roll of dice, are they liable for your money lost? Now imagine the gambling site going bankrupt while you still have $1000 dollars in it. Who's going to prove you didn't burn it off playing dice? It's a financial limbo and there really isn't specific legislation that will give you your money back, and that's the point I was making.

Unlike a gambling site, Bitstamp offers you an account history listing your actions on their page, which you could print as proof of the state of your account.


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Is cgminer used for both bitcoin and litecoin GPU mining?
I'm trying to figure out which software to download for my Ubuntu 12.04 box to start some litecoin mining.  Via google search, I keep coming up with cgminer for both bitcoin and litecoin mining.
How does that work, is the same software cgminer used for both bitcoin and litecoin mining?

Cgminer can be used to mine both LTC and BTC.  When executed to mine Litecoin one would need to add the command line switch --scrypt  It is also worth noting that the last version to support GPU mining and scrypt is version 3.7.2  Versions after that have all GPU mining capability removed.

All versions after 3.7.2 have GPU mining capability removed? As in anything newer than 3.7.2 has had GPU mining removed? Why is that?

going forward they will only support asic mining but I suspect the open source community will fork the project and potentially continue supporting gpus


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Longer fake block chain with "valid" transactions
What is preventing the bitcoin client from switching to a fake block chain that would be longer that current official chain? The faked chain would contain fictional transactions, but within the faked chain the transaction would be valid (e.g. like no double spends etc.).

related: http://bitcoin.stackexchange.com/questions/936/how-does-a-client-decide-which-is-the-longest-block-chain-if-there-is-a-fork

Bitcoin clients always accept the longest valid chain. On one hand, clients check the received blocks for validity, on the other hand length is defined by another metric than many assume. The length of the blockchain is the sum of the difficulty of all its blocks, not the number of blocks. So, in order to create a fake chain, the attacker would have to actually create a valid chain at the same difficulty. This is either possible for very short chains (double spend attack) or requires a major share of the network's power (51% attack).

Full blockchain nodes actually check not only the block headers, but also every transaction in the block body before accepting that block. If any transaction in the block doesn't "add up" (i.e. its inputs do not match the current accepted balance of those addresses, signatures, etc) then the block will not be accepted as valid.
This is where "light" bitcoin clients (the ones that do not download the full blockchain) have to trust a full-mode node to tell them the "truth" about previous transactions. If the full-mode node is malicious it can certainly trick these light client peers that are connected to it.


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Is declining number of peers (hosts) threatening the network?
I found out here that the number of total network hosts basically went down to 1/3 during the last year. Does this mean the network is less secure because fewer people run it despite the total hashing speed is still growing?

I found a similar question here: http://bitcoin.stackexchange.com/questions/9196/why-grow-the-bitcoin-miner-network

Kozuch, you linked to another post that is related to this issue.  However, your question and the linked post are two separate issues: the other question is asking why grow the amount of miners in the bitcoin network.
On the other hand, the question you asked is about the number of hosts.  Specifically, peers, also known as full nodes in the bitcoin world.  These are the people who run the full bitcoin client instead of multibit / electrum, which is the light client since they don't require hosting the blockchain.
The number of peers on the bitcoin network does not affect the security of the bitcoin network.  Whether or not there is 1,000 people running full nodes or 100,000 people, it makes no difference to the security of the bitcoin network.  What matters isn't the number of peers, but the number of miners.
I run a full node myself because I use Armory and Armory requires a full node.  But I am not surprised that the number of people who run full nodes has gone down by 1/3 in the last year.  There are two reasons for this: bandwidth and hard drive space.  I have a 25 Mb internet connection now, which is fast enough that the bitcoin network almost never slows down my internet connection.  But my old (much slower) DSL connection was immensely slowed down by the peer-to-peer bandwidth taken up by bitcoin.
A potentially bigger issue, at least for me, is hard drive space.  The bitcoin blockchain was about 9 GB when I downloaded it in April 2013.  I just checked my blockchain folder and it's now up to 20.9 GB, which is exponential growth in the size of the blockchain.  My hard drive is only about 221 GB, with 98 GB free.  I expect to get at least a couple more years out of my current computer, and if the blockchain continues its trend of exponential growth, I will eventually need to buy a bigger hard drive to continue hosting a full node.
So that's the long answer on why it's likely that the bitcoin network lost a lot of peers in the last year.  Short answer?  Running a full node is rather expensive in terms of bandwidth and hard drive space.


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Measuring total amount of Bitcoin in circulation
Since fractional reserve banking where money is created by lending is possible with Bitcoin is there a way it can be measured to give a total amount of money in the system? Such a measurement would actually reveal the value of money multiplier which I define as a real statistical ratio between commercial banks money and monetary base rather than a theoretical maximum ratio that is legally defined (because of lack of regulation with Bitcoin).
I guess such a measurement can either be direct (by lenders reporting how much they've lent) or indirect (measuring some other impacts those loans have on economy).

The concept of a money multiplier is meaningless in an unregulated environment. The money multiplier is, by definition, a legal limit imposed on the reserves banks must have.

You are not right. The multiplier is ratio between monetary base and all money in economy. Even if no legal limit is imposed there certainly is some lending occuring so the multiplier value must exist.

Correction: the ratio is of course the other way around.

@Kozuch No, the ratio is between the maximum amount of money that can be in circulation and the monetary base. This presumes some limit to the amount that can be in circulation. See, for example, the Wikipedia article you linked which says, "As a formula and legal quantity, the money multiplier is not controversial – it is simply the maximum that commercial banks are allowed to lend out" and "The money multiplier, m, is the inverse of the reserve requirement, RR". (Emphasis added.)

Ok, it seems there are multiple definitions of money multiplier either as statistic of or maximum "commercial bank money/central bank money" ratio (see linked Wikipedia, section "Definition"). I rephrased the question to remove possible confusion - I want to measure the "statistic" (real) value, not a theoretical legally maximum.


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Popularity based mining (variable block reward)
I am thinking of an alternative mining scheme where block reward would grow (or decrease) with popularity of the coin. The rationale behind this idea is to make an exchange rate more stable since greater interest will not result in higher coin price.
The biggest question is probably how to technically solve such variable block reward because there seems to be no easy way of how to collectively decide on reward height.

To echo the sentiment of my answer below: Market prices are exactly measures of popularity and they are very efficiently and effectively decided all the time. If you are speculating on possible future scenarios, I suggest thinking about ways people will try to leverage the celebrated information processing capabilities of prices and markets.

How would you define popularity? Any measure you make must be decentralised, and whatever you decide on can be arbitrarily faked. It's completely impossible in the terms of a trustless currency like Bitcoin.

Market price is a measure of popularity. Since there is no monopoly on exchanges anyone can run one. Then you probably want to count a VWAP (Volume-weighted average price) across the whole exchange market and you should be all set.

@Kozuch And how would you reliably measure that? What about lying exchanges?

@CodesInChaos: What exactly are you asking about measuring? I just proposed one way above (VWAP). There seem to be a real paranoia within the Bitcoin community in linking some "real world data" to the protocol - developers say it is a "vulnerability" and they will never do it - this is laughable. In the meantime, the only vulnerable thing here is Bitcoin itself... nobody knows whether it will be here tomorrow. Why an exchange doesnt want to lie? Because if people realized the exchanges would go out of business???

@Kozuch You did not say how you measure the VWAP and feed it to the protocol in a secure fashion. What if I open "Honest Achmed's Bitcoin exchange" and report that I exchanged a billion bitcoins for a dollar each?

Ok, I get what you mean now. Well each node would need to filter such exchanges out... If the exchange is new and nodes do not trust it, they simply would not use its prices within VWAP. In the end what we need is block reward height, so nodes have to calculate it somehow... maybe price is only one input for such calculation. Number of transactions (which also gives the economy value) could be another input. Actually the more inputs we have the less risky the final calculation should be...

I've recently thought of pretty much the same thing.
@Anonymous: Popularity is not difficult to define. Call the new currency bitcoin'. A good measure is the price of a bitcoin' in terms of some broad index of consumer goods (like the CPI basket), commodities, or whatever else you want. Perhaps the best available measure of popularity is MtGox's current price in USD, or EUR, etc.
If the bitcoin' price is high, the mining reward rises, essentially quickly generating new bitcoin', thereby lowering their price. A falling bitcoin' price would trigger higher mining rewards to slow the supply expansion.
Practically, at present, I think the extra stabilization provided by such a system would be minimal. But my opinions on the matter are currently not too strong.
Note that the current mining system already works to stabilize the price of a bitcoin to some extent: as the price of a bitcoin rises, more miners enter, increasing the supply and helping to drive down prices. But how's that system working out? So far, not so great as far as stability goes.
And of course, when the ~21M bitcoin cap is hit, there will no longer be any stabilization mechanism available that links bitcoin supply with bitcoin price.
UPDATE 1 I forgot to mention the important question of how "popularity" is announced/communicated into the bitcoin' system. Very good question.  One could imagine a trusted entity with a well-known public key signing such announcements and system nodes verifying that particular entity's signature.
One nice aspect: the "popularity" measure could be relatively objective, e.g., latest publicly available quoted price from a popular exchange. This would at least allow anyone in the world to determine whether this trusted entity is really trustworthy (are they lying about publicly available quoted prices???). But admittedly, this is a real sticking point in the design, e.g., what if this trusted entity is hacked?
UPDATE 2 Another related idea: if one could reliably enforce bitcoin contracts that involve trades of other real-world commodities/assets, then it'd be easy to construct a decentralized system in which many anonymous entities publicly announce bitcoin's "popularity" (again, use bitcoin's current market price as a proxy) and these announcements would be very reliable. (To be clear: the entire point of these announcements is to tweak the block mining reward to stabilize the bitcoin' price. The basic idea: reliable announcements of current BTC' prices are announced into the BTC' network. The mining block reward is constantly fluctuating depending on the current BTC' price. If BTC' is relatively high, the block reward increases, attracting miners. If low, the reward is lowered.) Just make these announcements into the form of offers to buy and sell bitcoin' for the commodity/basket/asset against which it's stabilized. For example, if the current market price of a bitcoin' is 1 USD, then an announcer might announce "I'll sell 1000 bitcoin' for 1.1 USD each and buy 1000 for 0.9 USD each". If the announcement is binding, then you can bet that announcement is not going to be disadvantageous to the announcer! One can reliably deduce a current price bracket for bitcoin'. Again, though, one needs a reliable way to enforce bitcoin contracts exchanging real-world commodities like USD.

You can determine the price in a decentralised way. Which exchange, how much is it weighted, is this exchange real? Who decides? It can't possibly work the way you think.

@Anonymous I don't understand your comment. And I don't know how to respond to "It can't possibly work the way you think." Why not? Of course, the systems I proposed are built on assumptions. In Update 1, I assume there is a centralized trusted entity that honestly announces price quotes. And in Update 2, I assume there is a way to enforce bitcoin contracts that trade the real world commodity(s) against which bitcoin' is stabilized. Outside these assumptions (which are, after all, assumptions), what is wrong with the proposals?

@Anonymous By the way, I believe that billions of USD worth of contracts are written and traded everyday whose payouts depend intimately on publicly available price quotes.

You assume there's a trusted entity, but there can't be one, that's literally the entire concept of Bitcoin. The rest is irrelevant. There's no way of having a decentralised Bitcoin "price", so we don't even need to consider anything outside of that.

"There's no way of having a decentralized Bitcoin 'price'." I think you are wrong here. Do we have one "monopolistic" exchange for Bitcoin? The answer is "NO" - I know at least several exchanges... So the exchange system is already a decentralized one with each entity having its own (decentralized) price. I guess you can agree with this, right?

@Anonymous I assume a trusted entity in Update 1, but not Update 2. And the entire concept of bitcoin is to remove the trusted entity that prevents double spending. Not all trusted entities are necessarily always bad. Personally, I'm open minded to their possibilities, though of course it's desirable to minimize their involvement for lots of reasons. Personally, though, I like my proposal in Update 2. But how to enforce bitcoin contracts for real-world goods? Gotta rely on "the man with the gun" for that, I'm afraid...

@Will Nelson: Why would you want to enforce the contracts? I think what you are talking about is more about "pegging" the bitcoin' to some "basket of goods" - do we really need that? I am happy with the idea of price showing popularity. I think the question is rather how to solve the variable block rewards technically within a network...

@Kozuch, The announcement contracts are enforced to ensure the announcers are making trustworthy announcements. That way there is no single trusted entity announcing prices. Anyone can announce the current "price" by saying "I'll buy for X and sell for Y". If their announcement is wrong, they'll regret it because someone is going to take them up on their offer and buy/sell bitcoin for a disadvantageous price. Do you see? And with this mechanism, there is no single entity you need to trust to announce prices/popularity.

@Kozuch, Yes, I was thinking in terms of stabilizing the currency with respect to some basket of goods. I think that, fundamentally, any natural definition of stabilization must ultimately rely on some type of average price of real goods. (That average price may be very indirect, of course, perhaps some market mechanism "computes" the average.) Why does BCT look unstable right now? Because last year a pizza cost 100 BCT and now a pizza restaurant costs 100 BCT. It's all relative...

@Will Nelson (replying to your previous comment - not your very last one): Well I still can not get the point. You seem to contradict yourself (not meant to offend you). Well, with several exchanges (BTC China, Mt.Gox, Bitstamp etc.) we already have a decentralized prices and is such a price what you want to create with your enforcement? And I think the traded volume at a certain price point is what makes that price legitimate? So you basically would be looking for a price where the trading volume was rather high.

@Will Nelson: Your 100 BTC for pizza or pizza restaurant is a volatility issue - variable block rewards should eliminate such volatility.

@Kozuch Where's the contradiction? How do you eliminate the need for a centralized trusted entity to announce popularity? Make it so anyone can announce popularity. How can you trust a stranger's announcement of popularity? One way is to have the stranger make his announcement in the form of a legally binding contract: if he says, "I will buy 1 BCT for 1USD or sell for 2USD", you know the price of 1 BCT is likely between 1USD and 2 USD. No trust required. But I think your point is that this idea duplicates an exchange mechanism (e.g., Mt Gox). True. That's perhaps a shortcoming.

@Kozuch. Well, yes, you basically repeated my "pizza" point. If the price of BTC were constantly announced into the BTC network and the block reward constantly adjusted in response to these announcements, it would tend to stabilize BTC with respect to real world goods. The price of a pizza in BTC would be more stable. That's the whole point...

@Kozuch - I'd chat, but SE won't let me, it seems. Perhaps you misunderstood. See the paragraph of my response beginning, "If the bitcoin' price is high...". The whole idea of all this price announcement stuff is to tweak the block reward up or down to stabilize the bitcoin' price...

Yes so we can agree to have a (trusted) price announced somehow (I propose looking at exchanges - see my comment about VWAP). But I was told it is not so easy to make variable block reward work technically (in terms of software client). So I rather want to focus on the coding part since the theory seems to be cleared. Can you help with software engineering?

So then we have a "trusted" central exchange which can be shut down to destroy the coin. That's exactly what the system is designed to stop, central control that can be disrupted. This has been proposed on bitcoin-development more times than I can remember, and it's consistently shot down, actually inducing mirth in the core team. See this similar idea http://sourceforge.net/mailarchive/forum.php?thread_name=CA%2Bs%2BGJDJA7_HOiJ-_jazXERSYfWvO-DHk89ih4pG8dEK5K9Z9A%40mail.gmail.com&forum_name=bitcoin-development

@Kozuch I understand your concern now. I'm not a BTC code expert (quite yet), but the idea is currently completely technically feasible within the framework of BTC. Obviously, it would not be at all backward compatible, if that's what you're looking for. My guess: The block reward code is hardcoded and all nodes must perform precisely the same reward calculations or different nodes would be accept/reject blocks differently. No way it'd work with the current installed base.

@Anonymous: Well, I dont really care what the "core team" thinks. Sure they want to preserve status quo because these people hoard the most BTCs in existence and they want the price to rise and are naturally against any self-regulatory mechanism. The trend with exchanges is decentralization I think - you can not deny this fact. Yes, more time will be needed for even more exchanges to spring up and help build even more decentralized price. But we are heading that direction already.

@Will Nelson: Yes, we are talking about new/forked coin (alternative chain) so compatibility with Bitcoin is a nonsense and is not wanted. I thought like this: every node would propose reward value. The node creating new block would read all proposals and choose median value. If it fails to obey this value, other nodes will not include its block into the block chain - effectively not giving it any reward at all. But I am not sure how (or if at all) this is technically doable. But you say it is doable?

@Kozuch You would be greatly mistaken in thinking that.

@Anonymous Thank you for the pointer to the mail archive. That was useful. I'm quite sure the developers are laughing because of course BTC can't be changed at this point. It would (I'm pretty sure) clearly kill the currency both technically (forking everywhere) and economically. As mentioned on the list, you'd be changing the rules of bitcoin midstream -- exactly the type of garbage many of us want to prevent. There's no way to implement this idea without creating a new currency from scratch.

PS. I asked about feasibility at #bitcoin-dev on Freenode... was probably a completely wrong place to get a positive answer because of reasons Anonymous stated above - they simply dont want to support anyone making such fork, because the new coin will bring Bitcoin to hell :).

@Kozuch That protocol doesn't sound right to me. And that'd be a BIG change to the BTC codebase. How can you verify medians with nodes coming and going? And who's a "legitimate" node in the median calculation? And I'm not quite sure that solves the problem. Again, the problem of stability is, basically, one of relatively loose linkage with real world commodity prices. The idea I had in mind was: (1) special transactions announcing current price is broadcast to all nodes, (2) nodes "authenticate" price announcements by either looking at a signature with one of N well-known public keys or...

through the binding contract mechanism I described in  Update 2, then (3) block mining rewards are tweaked in response to latest price announcements. This seems like an easy modification to the BTC protocol and codebase (I think). But it's far from backward compatible.

@Anonymous: Greatly mistaken in thinking what?

@Will Nelson: I am open to any SW solution, particularly simple and inexpensive one :). I like your protocol proposal very  much! Regarding point #2 - I would go with the public keys since you can not do binding contract easily in P2P. I guess the holder(s) of those public keys would (have to) be publicly known and real (not anonymous) persons? If so, that could bring some more trust to the network which would actually be good.

@Kozuch Maybe you can ask the BTC core developers or some similar group how difficult it would be to fork the BTC code and implement. (Please let me know if you learn anything interesting!) More ideas just off the top of my head: each "coinbase" transaction could take one input (instead of current 0) that points to a special "price" announcement transaction that determines its block reward. And special public keys would be hardcoded into codebase distribution. (That's typically the way SSL works with its certificate authorities. Research that for more info.) Good luck!

@Will Nelson: Thanks for all your valuable contributions to the topic! I dont know how fast I will proceed, my resources are naturally limited. I will see. I rather try to spread the word, occasionally finding someone who does not like status quo too :).

Howdy folks, this comment thread is getting pretty long - please consider moving this to [chat] if you've got more to discuss - a link to the transcript will be here so folks find the conversation.

The block reward amount could be solved making it based at hash rate, this assumes that when you have bigger hash rate it means the coin have more value.
Imagine you have a coin with a block time of 8 minutes and 525960 coins.
First you would decide the amount of time you would want all coins to be mined assuming a hash rate of X. Lets assume you want 8 years, this means 525960 blocks assuming 8 minutes of block time.
This means that (with a hash rate of X) to get 525960 coins needing 525960 blocks to get it, you would need an reward of 1 coin per block.
Now that you made that math, you will have your default block reward value (1 coin with hash rate of X).
The real block reward of each block will be 1 / ((Hash rate) / X).
As some example with X being 10, if the hash rate become 2x times that, a hash rate of 20, the block reward become 1/(20/10) = 0.5 coins


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Electricity cost of mining
I've checked with my electricity provider, and I have been told the following:
Unit Rate (per kWh) = 0.1399USD
Standard Charge (per day) = 0.1645USD

While mining, if my computer is using 100w (which is a reading my electric monitor is giving me).
How do I work out how much this miner is costing me per hour in terms of electricity usage?

Not sure what Standard Charge means... I'm assuming it's the fixed cost you pay regardless of usage. So if you want to keep toasting your sandwich in the morning you can ignore it in the context of mining.

Basic Algebra 101:
100 W = 0.1 kW

so
0.1 (kW) * 0.1399 (USD/kWh) = ~$0.014 (USD/hour)

or
0.1 (kW) * 24 (h/Day) = 2.4 kWh/Day

2.4 (kWh/Day) * 0.1399 (USD/kWh) = $0.3358 (USD/Day)

Except KW/H doesn't exist. And any science 101 would tell you to be accurate with the unit symbols, including case. Kilo is lower case k. Watt is upper case W (wrong in question, not your answer). Hour is lower case h as in kWh. It's not about being math Nazi, it's about reducing risk of mistakes and making calculations actually understandable to other readers. I'll edit your answer.


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How to work out my hardware's hashrate power
Using my existing hardware, I want to work out which altcoin is still profitable to mine.
I have found this link:
http://dustcoin.com/mining
But don't know which values to enter into the boxes at the bottom of that page.

How do I work out the SHA-256 and scrypt hashrate
For the Power(W) box, do I enter in my computers PSU wattage? I think it's 650w
For the Power Cost ($/kWh) box, do I check my electricity bill to find out how much I am paying per kWh?

How do I work out the SHA-256 and scrypt hashrate

You can look up your hardware e.g. here (BTC) and here (LTC). But I think it's much easier and more accurate to just try mining different coins for couple hours and measure hashrate directly.

For the Power(W) box, do I enter in my computers PSU wattage? I think it's 650w

PSU wattage is max. power it can supply, so it poses upper bound on PCs consumption.
To get accurate measurements, you can use something like Kill-a-Watt. Or you can look up TDP of individual components: CPU's, GPU's and ASIS's power consumption is usually listed in their specs, and motherboard+RAM+HDD together usually use around 50W.

For the Power Cost ($/kWh) box, do I check my electricity bill to find out how much I am paying per kWh?

Yes.

authors: виталий кочетов


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How does mining work
I have a basic question on mining.  How does it work?
For example, if I use my computer to mine coins such as litecoins, do those coins go straight into my offline wallet?  Or must I be connected to some online centralised pooling service, which holds to coins until I transfer them to my offline wallet?

You will most likely be using a mining pool, in which case the coin you earn will remain on your pool account until you choose to withdraw it to your local wallet. Most pools support auto-withdrawals (i.e. when the balance reaches a certain threshold).


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Choosing a mining pool
I've read that some mining pools disappears all of a sudden, and your hard earned coins also disappear if you didn't transfer them ontime.
My question is, how do you go about picking a pool which isn't going to disappear?
I've not done mining before, but want to try out litecoin mining.
Or is it better for me to start mining without using a pool if that's possible?

If you are starting off, I will assume you do not have the computing power to solo-mine.
It's just easier to join a pool, and with regards to trusting one, I would stick with something that has been around for a while. For Litecoin I've used wemineltc and have no complaints.

I guess you have seen https://litecoin.info/Mining_pool_comparison, and you are really interested in finding out Litecoin's equivalent of https://blockchain.info/pools to discover the pools that are likely to be around for while?  For a P2Pool LTC mining pool operation, see http://pool.fabulouspanda.co.uk:9327/static/.

I think the best pool it that has minimal ping response time to your mining PC. I have found mining pool lists for different coins with ping monitoring: https://investoon.com/mining_pools/


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Browser based mining
What happens if while mining, you lose internet connection?  Do you lose all the work your computer has done, or is something like bitcoin-plus smart enough to post the data across when the internet connection has been re-established again?

Ask bitcoin-plus

The work done when mining is not accumulated over time.  Each hash calculated is independent from the others.  Think of mining as repeatedly rolling a huge die and trying to get an extremely low number, instead of working towards a solution of a complex problem.
If a miner loses connection to the internet, it will be unable to submit work during this time period.  Work done during the outage may or may not be stale (too old to submit) when connectivity returns.  However, no previous work will be lost, as this work would have already been submitted immediately to a pool/the bitcoin network if it was useful.


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How to quickly check your mining speed?
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?

If you've found this question trying to figure out how to get rich mining from your laptop, please read: In the ASIC-age, is it worth starting mining Bitcoin at home?

Very good question. Today I created a page at my pool for this purpose: http://bitminter.com/test
You don't get paid without registering and entering a name and password. But it is useful for the purposes you stated in the question. Just click the "test start" button. You need Java installed, and of course GPU drivers with OpenCL support if that's what you want to test.
PS: Thanks for the idea for this.

Pretty good implementation, although it seems to be mining at about 75% speed of some other miners. Is there some way to pre-set some credentials by altering the .jnlp file?

At the moment it doesn't run well with the latest AMD drivers. Credentials are usually typed in and saved along with other settings. But this test version runs as a test-user every time.

I cant see a test button, has it changed :(

There is a round button with a green light and the text "TEST START". When it asks for a user name type in test. Note that in 2017 the bitcoin hashrate of a GPU doesn't matter as all GPUs are too slow to put a dent in bitcoin mining.

downloads test.jnlp and errors about cert https://pasteboard.co/GFo2SwY.png

Yeah, the certificate the app was signed with has expired. But in 2017 your PCs hashrate is essentially zero. It doesn't matter which graphics card you have. You need to buy an ASIC miner.


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How can Bitcoin change the world?
Let's think of a hypothetical scenario if Bitcoin becomes the world's major (most used + highest market cap) currency one day. How will it change the world? The obvious point is cheaper money transfers, but what about its impact on the global economy? Is a "deflationary" currency better for the world? Is quantitative easing really that bad?

I like this question1 - we don't get many big picture questions.

How could Bitcoin change the world?

A mature digital cryptocurrency could reduce trade barriers and thus
increase the rate of productivity dispersion throughout society. As
money is a form of fungible authenticated information2,
non-proprietary digital money gets to take advantage of the
information age to rapidly democratise trade with lower
transactional friction.
It could encourage governments to move towards a more rational global
currency or currency basket for sovereign wealth reserves, trade
imbalances and protection from commodity price shocks. In effect the
phenomena of democratised digital currencies, if not Bitcoin
specifically, could accelerate global cooperation and democracy in
macroeconomic practices badly in need of an overhaul.
It could provide an excellent educational opportunity for teaching
and learning macroeconomics. As the cryptocurrencies are moving
though the stages of currency development so fast as to eliminate
most of the confounding factors of studying more mature currencies
that evolved over several centuries of political and socio-economic
change.
It could enrich a very small minority of early adopters. Depending on
what these early adopters do with their new found wealth, they could
bootstrap other social improvements.
It will probably not result in increased (effective) tax evasion due
to the wide range of levers available to collect tax revenue.
Although an increased informal sector may result in governments
shifting towards regressive taxation such as consumption taxes to
offset the evasion of progressive taxation.
It will probably not result in a cap on the money supply due to the
ability to establish fractional reserve banking on top on any specie
currency if legally permitted. Off-block chain Bitcoin clearing
houses may evolve into fractional reserve banks to avoid on-block
chain costs. In either case, it will not provide an economic solution
to a political problem (deficit spending).
It will not create a libertarian or objectivist paradise. Such a
shift in socio-economic paradigm will require both economic and
social consensus. Cyptocurrencies can provide an economic consensus
only.

What about its impact on the global economy?

Probable impact: Low to Medium. Possible impact: High.
It really depends on how willing various cryptocurrencies are to absorb certain "bad" aspects of fiat currencies in order to grow into a major currency with global volume. At current, I don't know what level of actual impact is likely - since you have to predict not just technology but the behaviour of people: Both of those that use or might use Bitcoin and the adaptations of its traditional and contemporary competitors and their mindshare.

Is a "deflationary" currency better for the world?

A qualified no3.

Is quantitative easing really that bad?

A qualified no3.
1. In case people think I'm a curmudgeon.
2. Each coin I have is information that the world currently owes me X amount of    goods and services.
3. I can't do these questions justice in an answer primarily about how Bitcoin might change the world. Suffice to say we are currently trapped within a "growth" orientated socio-economic model which is incompatible with non-inflating money supply. The lack of true democratic control over the objectives and priorities of these federalised economic levers is a problem.

Excellent answers as always:) I'm  wondering about the money supply issue though. It seems to me that the transparency that the blockchain provides would make bitcoin-backed fractional reserve banking impossible. Isn't it based on a fundamental degree of deception?

Fractional reserve banking (FRB) is a mundane offshoot of promissory notes, an innovation that allowed trade networks to transfer reputation instead of easier-to-steal gold shipments between branches in far-flung parts of Europe. These traders became bankers (as in you can bank your notes/scrip) and eventually institutions. I recommend The Count of Monte Cristo as it provides fascinating insight into the early banking system. Any Bitcoin gateway or clearing house is by definition a bank in the historical sense as you are using banking services.

To detect FRB on Bitcoin requires to know the volume of on-block settlement trade ("gold") between clearing houses versus the volume of off-block trade ("notes") within and between clearing houses by normal end-users. As long as you can redeem your gateway's off-block notes (their wallet) for on-block coins (your wallet) it functions like any other bank. Eventually the reputation of the off-blockchain network is such as that few people bat an eye when settlement trade switches away from the energy expensive on-block protocol (i.e. Bitcoin as we currently know it). Bitcoin as preliminary Fiat.

@BrianFabianCrain The drive towards a fractional or even completely fiat Bitcoin can occur without deception and regardless of any gold-emulating ledger protocol it initially starts with. Most people are rational microeconomic rather than macroeconomic actors. If the off-blockchain networks provide better services at a cheaper price than DIY on-blockchain transactions, then the off-block network (money supply of Bitcoin notes) will outgrow the on-block network (supply of Bitcoin specie). The same factors that drove society away from a Gold Standard can and likely will apply to Bitcoin.

This is a great question and it's something I spend a lot of time thinking about. In general, I'd say no one really knows at this point and it is difficult to make more than a few guesses.
So let me have a try at that:

Banks would lose much of their ability to control the monetary supply, interest rates and exchange rate.
The financial sector would shrink and become less profitable. Probably a good thing.
It would become more difficult for the government to collect taxes.
Loans would be taken out more rarely.
Leverage would mostly disappear from the financial system.
Economic and financial transaction would not be restricted by national borders.
Individuals would gain more control over their own finances and money.
Governments would lose the ability to finance their expenses through increased debt. They'd have to run more or less balanced budgets instead.
There would be enormous redistributions of wealth as the shift to bitcoin occurs.

These are some of the things that come to my mind, but this list could be continued for a long time. I think it's save to say that these would be revolutionary changes and we would end up with a radically different world.
Will this actually happen? I don't know but I think it's possible.
Will the changes overall be positive? Impossible to know, but I'm optimistic.

People are controlled through their money, and fiat currencies eventually fail. Bitcoin is an option to maintain capital without resorting to hostility. "Quantitive easing" is a fancy name for distributed theft. Theft is bad even when people claim a greater good.


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How does the Chinese Bitcoin ecosystem differ from the European/North American ones?
What is the background of the whole Bitcoin ecosystem in China? Their market has been growing insanely in the last days... but I guess it can be very specific (different mentality of people, the Yuan, infrastructure etc.). How is their market different from the European/North American ones?

The Chinese are intense savers and frugal. Their interest in Bitcoin will involve relatively small price corrections.

Do you want to say the will be resistent to price drops (in the bubbles for example)?

Yes. Bubbles will still happen, but the correction would be less severe because Chinese investors tend to buy-and-hold through the ups and downs. They save a little at a time and don't spend anything until the need to (and the price is high). Being frugal would mean that they'd buy bitcoins when the price goes down rather than panic sell on a momentum trade. Last evening was an excellent example. The bitcoin price should have had a major correction last night, but it was only a minor dip. China investment is increasingly moving the prices.
Chinese people have modest incomes but they save everything. They are limited by law to only having two homes, so you sometimes find children owning homes. They are modest homes, but often the land they sit on (like in Beijing) can be worth millions for new building construction. They invest in family, businesses, real estate, metals, and increasingly bitcoin. China is like America used to be when people were more interested in producing and achieving than consuming and taking.
Lawyers and regulations rule the US. There is no liberty because someone might get hurt. China has little of that. People are free there in many ways that the US is no longer. People are happy and enjoy life there. The bad side of China is well hidden, and is diminished through increasing prosperity.

I dont really understand your answer. Could you elaborate the reasoning and implications once again more simple please? Do you want to say the will be resistent to price drops (in the bubbles for example)?

@user7636 What's up with the last 2 paragraphs, they just praise China, what do they have to do with Bitcoin? Btw are you Chinese yourself (the way you talk in the last 2 paragraphs made me think that)?


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Alternative: Mining scheme driven by logistic function
Could a mining scheme driven by logistic function bring a greater price (= exchange rate) stability to a crypto-currency in comparison to Bitcoin for example since it better models natural growth?
Simply the monetary base would grow according to this function. This would mean that till half of the scheme period block rewards would rise from 0 coins to X coins and in the second half fall from X to 0. After the scheme's period would be over and all currency had been mined, transaction fees could be introduced to keep the system working.

Picture: Chart of logistic function (credits: https://en.wikipedia.org/wiki/File:Logistic-curve.svg)

What do you mean by behavior? Are you talking about price fluctuation or rate of creation. Rate of creation for bitcoin is incredibly predictable because that is the nature of the algorithm, and if your talking about price, then perhaps, but I would argue that any currency that is rapidly adopted will always be subject to large deflation.

Yes I mean price fluctuation... edited the question accordingly. Well, the large deflation could be minimized by the logistic curve in its middle I think...

I think this is a viable idea and is worth exploring further, Are there any alt coins employing this function yet?
I have been thinking about it for over a year now and see that with Bitcoin by having the early adopters hold a majority of coins helps to preserve the original protocol, as those invested in the system stand to lose the most if it is changed.    The result is as the Bitcoin network grows the protocol and clients side use of the network is strengthened by the coins that will remain with the preferred fork.
With the normal distribution model facilitated by a logistic function, early adopters will not hold as much influence in keeping the original intent of the protocol intact, as early majority adopters will hold the most influence.
There are possible alternates like a proof of stake, mining option that could be reworded for maintaining the original blockchain, and can be redeemed/ utilised as a stake to mine, thus regulating mining growth with that of maintaining the growth in bandwidth and storage. (allowing for 2 specialisations: 1) mining coins - 2) maintaining the block chain.
The result is when mining jumps significantly: 1) early adopters can sell their mining options (maintaining the original protocall) 2) the market demand to mine more is held in balance with bandwidth and storage growth. (making it more environmentally viable and allowing for greater decentralised block chain storage.)
Ie. the protocol stake holders are the ones who maintain the block chain. And to do a 51% attack you would have to strengthen the base network, I can imagine preventing modification of the block chain.

I havent really found an altcoin with such logistic mining scheme.


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Inflationary (no total coin limit) cryptocurrency where miners keep all new coins
Is there an inflationary cryptocurrency with following features?

No fixed limit on total coins (coins will be emitted forever).
Miners are the only source of new coins.
Mining reward (new coins) go all to miners.

I found several inflationary ones like Freicoin or Devcoin, but they seem to have various hybrid models where newly mined coins are (at least partially) transferred to other subjects than miners (various foundations, developers etc.).

PPCoin and its offspring NovaCoin have an infinite money supply - even though the reward for blocks gets diminished over time (as in Bitcoin et al.), as the money supply increases there will be more and more coins offered as reward for simply hoarding the coin.
There are also built-in deflationary mechanisms for destroying coins with every transaction, so hopefully the money-supply would self-adjust: increasing or expanding as needed, depending on how much it's actually used.

GRouPcoin is an inflate-forever coin (50 coins per block forever, not halving/halting like multiple others) and all proceeds go to miners.
http://devtome.com/doku.php?id=groupcoin
It is the predecessor of Devcoin.
Rarely used but has recently been one pool mining it (bitparking).


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Sudden Drop in Hash Rate GeForce 650 GPU Card
I'm running on a 15" Retina MBP and have just been playing around with mining on it a little bit.  I realize GPU mining is almost dead at the moment, but bear with me.
Overnight last night I was running the BitMinter Java client and getting around ~20Mh/s.  I fired it up again this evening, and for some reason, am now only getting around 5Mh/s.  I'm seeing the same rate on both the BitMinter java client as well as with cgminer.  Nothing has changed on my system over the last day other than having to reboot it a few times for other reasons.  Does anyone have any idea why my Mh/s output rate has fallen so much?

This isn't one of those Macs with two GeForce GPUs, is it? They run the slower GeForce when running on battery, to save power. If power saving is turned off they can actually mine on both GPUs.

It has 2 GPUs. A 650M and the Intel HD4000, but the 650M is always active when a miner is running.  In fact, even switching it so that the 650M is always in use causes no difference.

I think I figured out my own issue here.  I reset the SMC on the macbook (http://support.apple.com/kb/HT3964) and my GPU performance is back to normal.


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Recovering bitcoins after the owner's death
My Brother died in April and we believe he had a bitcoin account. Is it possible to find out how to recover/take over his accounts?
I know this is a new form of currency but it seems odd there is no way of recovering information in these circumstances.
Any help would be welcome. I still have all his computers, so can anything be traced through them?
Thank you.

Very sorry for your loss. Assuming you can recover the wallet.dat and his password, it's possible to retrieve the coins. Let's start with the first step: do you have physical access to the machine he was using?

There are two main ways someone can hold Bitcoin

On an Exchange or Online Wallet

or

Privately on a computer in a wallet or offline private wallet

For (1) you will need to obtain the username and password to access the account.
For (2) you will need to login to the computer and, depending on your luck, if the wallet is not encrypted, you should have access. If the wallet is encrypted you will need the password to transfer/spend the coins.  If you do get access to the computer then look for the bitcoin application and run that to see if there are any BTC in the account.
If your brother had a paper wallet then you will need to find this information as it will have public and private keys to access the coins. These can be imported into a wallet to give access to the funds.
Unfortunately, if you cannot find the info above the coins are lost. There is no central control of this currency so there's nobody you can contact for help.

Good point  https://en.bitcoin.it/wiki/Clients

There is no general answer for all cases; it will depend entirely on the ways he chose to store and secure any Bitcoins, which vary a lot from person to person.
You will need to have a trusted person look through his effects, both digital and physical. This person should be both an expert in the systems your brother used, and Bitcoin itself.
If this person is able to access his computer, phone, and backups – not just physically handle them, but also examine their digital contents past any logins or local encryption – then it will be more likely they would be able to determine whether he had any holdings. Similarly, access to his email accounts, or any other notes about logins/passwords, would help.
But even finding confirmation of his holdings might not grant access. In typical cases, the ability to control a Bitcoin balance is limited to those who know an impossible-to-guess secret (cryptographic private keys). If he hasn't left any accessible copies of this secret, or all such copies are protected by a strong unique password that you can't guess, there's little hope. The balance is lost to the world, and essentially destroyed – no one else will access it either (so no one else can 'give it back').
Your best bet might be if he held balances at businesses that verified his true-life identity via banking links or government-issued IDs. (Examples of such businesses would be exchanges and payment-processors like Coinbase or MtGox.) In such a case, with reliable information that he is deceased and that you are his rightful heir, the balance may become available to you. (For a long-lived business operating under usual laws, his absence for a long-enough time could trigger attempts to contact him, and perhaps transfer of his abandoned property to a governmental entity, such as a US state's lost/abandoned property agency. I've not yet heard of this happening with Bitcoin, but consider it likely in the next few years.)
Alternatively, if he used a local install of his own wallet software, such as the original Bitcoin-QT, Multibit, or Android Wallet, you might gain access to the balance if his local security was no greater than the machine's own login-screen/lock-screen (and especially if you have that password). Such local wallet programs do not necessarily add extra unique passwords. Where they do, that password could be a fatal block – or perhaps something something family or heirs could discover or guess.
Finally, if he held significant amounts for the long-term, he might have printed/written private-keys. ("Cold storage", for slow access much later.) Again, an expert would likely recognize the usual forms of such keys, if they see them among papers/notes.
Ultimately, though, in such cases you are hoping that he left sufficient clues, or otherwise chose to leave his devices or papers in a state where later possession would be enough to access the Bitcoins. Some people do this; others who are more careful or paranoid do not.
If you had a strong indication that the amount was very large, and no simple efforts succeed, there's always some chance that heroic, expensive efforts – as might be used by a digital forensic investigator in a major legal or historical case – could enable access, even against the owner's careful intent, because of mistakes or unintentional information leakage. (For example, incompletely-deleted remnants of an earlier unencrypted wallet file might remain on a hard drive or old backup, or access passwords might be brute-guessable variants of other passwords leaked via other caches.) But, such approaches involve serious expertise and cost with no guarantee of success.
I'm sorry for your loss and wish you luck in discovering and accessing whatever Bitcoin balances that might exist.

I am really sorry for the loss of your brother.
I know some/most of the exchanges require account holders to be verified to trade and move cash around, i.e. Know Your Customer, which involves providing proof of address, citizenship etc.
Could be worth checking their policies on death of account holders and whether they accept any kind of certification as proof of death and 'rights' of access.
If you think the wallet represents a large value, it may even be worth seeking legel rep and engaging the online exchange/wallet company through those means.
For what it is worth (perhaps for the benefit of other curious readers), a service like SecureSafe.com provides a solution for these tragic events.
To summarise it provides for 'digital inheritance'; amongst other things, you can manage beneficiaries of your digital data, whether it be a PDF document, online banking access details or in this case Bitcoin Wallet access details... or even a Bitcoin Wallet backup file in its entirety.
Good luck

and sorry for your loss.
You might do a file search for "wallet.dat" on his computer(s), and search the entire disc(s), including subdirectories, and hidden files.
Note which directory it is in. If it is in a "bitcoin" directory, you may have found the wallet. If you did, then just try and launch his bitcoin client (program) and see if you can access the wallet data. If it somes up, it will show you a balance.
If there is no balance, then any BTC that he had, might have been kept in an "exchange" wallet, or paper wallet, somwehere on the internet.
if there is a balance, it can be transffered to another wallet, or sent to an exchange for cash value. It could, possibly be protected by an encrypted password, which you would have to figure out, before you can do anything with it.
Look for a text files, also, (.txt file), that may contain his login and password(s). These could be under any one of a number of programs, like microsoft office, notepad, wordpad. etc.
You need to give a bit more information, sowe can help more.
Which operating system was he using (windows 7, windows xp, etc)
This might let us tell you a bit better, what to have you look for.
Otherwise we are all guessing.
I keep mine information in a text file, called "(something)_login.txt", and I keep them encrypted, but I always keep a copy of the password. He ,might, also, keep them on a usb stick, if you see any laying around, which is the safest way to keep them.
You ,might look for any file on the disc, named "bitcoin*.*", with your file manager, under "search"...or files named "exchange.*", or any file with an exchange's name, such as "mtgox*.*". This might give you a starting point.
I can give more explicit instructions, if I know what operating system he is using (windows 7, windows xp, etc)
If you were close to me, I could come do it for you, for free.
Others might charge you a fee.
If the file in encrypted, it may be a bit harder to access, as you would have to try and figure out what passwords he might use.
One thing I might, also, suggest, is that of you  have a computer geek friend, let him/her have a look around on the computer, to help, but keep an eye on him/her, as I trust no one. Don't let anyone remove anything, period. Make them work on it then and there.
BTC is worth a lot of money,, and you could loose a substantial amount, if he has been doing this for a while.

I am in the same boat I still have my late husband computer but knew I couldn’t retrieve his account because it had to be a two way verification meaning that the phone number he listed was his old phone from work witch I no longer had possition of.
While reading his mail that he occasionally received I received a notice about a fork in the bitcoin and to choose wisely. That was my first realization there was an account. It had been open a week before his passing due to an accident. I was able to reach the operators of this bitcoin service.
I had to provide a death certificate, last will, probate And a letter of intent. I am at the last stage of his coin or coins being transferred into an account that I created with same bitcoin service. It has been a long road on this one but you can get them. Another thing is you have to send email via his email account that he established when he was alive once you can prove these details you can establish your own email and open your own ticket to the same issue using your email address I hope this helps you. I am sorry for your loss.

Without mentioning which service you're talking about, this answer is rather useless.

authors: Ольга Иванова


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Is ASIC Bitcoin Mining Profitable?
I’m pretty well versed in Bitcoin trading but am really new to Bitcoin mining. I hear a lot of conflicting views regarding the profitability you can achieve with Bitcoin mining. I was wondering if I’m better off mining Bitcoins or to try and look into mining other crypto currencies such as Dogecoin or Litecoin.

related: Why does mining profitability tend towards zero?, How Much Bitcoin will I mine right now with hardware x?

The short answer is "no", for a very simple reason. Any time Bitcoin mining is reliably more profitable that anything else people could do, then more people will be doing it, which raises the difficulty. So the difficulty will rise until Bitcoin mining is not going to be profitable for the average person. If you have some special advantage, such as paying a particularly low cost for power or you need electric heat anyway, then maybe,

Bitcoin mining market behaves as a very close real world analogue of a perfect competition market, one of whose characteristics is precisely that profits tend to diminish to almost the level of costs. I.e. the only way you can get rich is by continuously innovating.

This question has been asked before here and here but this was a long time ago before the difficulty leaped in November of 2013. Bitcoin mining is getting more and more difficult as time progresses. This is because the Bitocin protocol is designed in a way that the mining difficulty increases as the network’s hash rate increases - This chart shows Bitcoin difficulty over time. Hash rate is the computing rate of the system - so the more miners come aboard, the higher the difficulty for mining Bitocins - This chart shows the network’s Hash Rate.
Today if you want to mine Bitcoins you will probably need to join a pool of miners working together in order to compete with this difficulty. For a detailed explanation look here.
If you want to calculate exactly how much you can make with Bitcoin mining use a mining profitability calculator like this one. From my own experience I can say that using the most powerful home-made miner you can make a few hundred bucks per month which usually would barely cover electricity cost. Here’s a real live example from a guy on Reddit.
One more option to mine would be CEX.IO which is a cloud mining service where you basically buy mining capabilities without the hassle of operating your own miner. I haven’t tried it myself so I can’t recommend it.
If you want to mine Bitcoins today it will probably be purely for hobby or ideology. You can however try mining altcoins and then exchange them for Bitcoins. The problem is that there are so many altcoins it may sometimes be hard to know which one is worth wasting the time on. This chart shows you some sort of a mining profitability indicator for different altcoins. So even though you may have “missed the bus” on Bitcoin mining you can still try to mine altcoins.