Another great idea in this thread.  Maybe this platform (or one like it) could be leveraged ( https://www.hackerrank.com/ ) to support a Bitcoin challenge track?

Something that is a series of "courses" which starts with the basic like installing bitcoind, moving the data directory, configuring config file, etc.  Higher level courses could cover RPC calls, pywallet, creating watching only wallets.  Highest level courses could cover raw transactions, message internals, modifying the source code, etc.

I agree.  GetPubKey would be a great RPC addition.  Also thanks for that walkthrough.  I may try this out on testnet and later with a token amount of BTC on main net.  I would caution anyone looking to "play" with raw transactions you can permanently lose funds by creating flawed raw transactions.  Use testnet, build testable software (even if it is just some scripts) to create the raw txs, and only move to main net once fully tested.   

Not really, I recommend reading the entire thread.  Switching to hashes only is more like a 20x reduction in size.   Also the fees being 1/30th of "orphan cost" is just one estimate.  Other estimates put it closer to 1/10th.  Miners also receive a very large subsidy and they have an indirect incentive to keep the network going (a few less Bitcoins which are worth something is more than a few more worthless Bitcoins).  Also Moore's law is alive and well and it applies to bandwidth as well.

Still even if fees rose 300% (which I strongly doubt) that would make the cost of a Bitcoin tx something on the order of $0.20 which compares very well to other payment methods.   What I think is more likely is miners dropping or reducing the number of free transactions they support and maybe the min fee doesn't go down.   That combined with the subsidy, improvement to block propogation, and the power of Moore's law will likely keep tx fee costs below $0.10 or so.

That is exactly why they buy them.  They want to try it out.  Just understand if you buy a USB Miner for x BTC (and if you paid USD you could instead buy x BTC) you will be lucky to earn 10% of that back in your lifetime.  If you want to buy a USB miner to "try it out" well go ahead just understand that you are guaranteeing a 50% to 90% loss as a cost for that education.  If you are fine with that then go ahead they are a great way to learn how the system works, however if you are buying them thinking you can pay x BTC and end up with 5x BTC you are going to be very sad in a couple months.

It has been highlighted in meta a dozen or more times.  The view of the admins is that this forum is Bitcointalk, and anything non Bitcoin related is off topic.  The altcoin sub forum is the same as the off topic subforum it exists for the SOLE REASON of making the mods jobs easier.  If there was no altcoin and off topic sub forums people would still post about altcoins and other off topic posts but it would just be spread out all over the forum and would lead to more mod work.

It is NEVER going to change.

I love the anti-rad idiots on the web.

Summary - if a lethal radiation cloud moving at 10mph is heading towards you and (is hundreds of miles away) you should NOT I repeat NOT simply leave the area.  Instead you should try to duct tape your entire house.

There is set the subforum to ignore in your profile.

+1.

KNC has its problems but they are nothing like HF who blatantly lied to customers to defraud them.   If after, anyone buys from HF because they are a deal well you are an idiot.

Well in that scenario the grandfather could spend the coins however using multi-sig one could "lock the coins"

Create multi-sig address P2SH which requires 2 of 2 signatures to spend. Grandfather sends the coins to the address.   Grandfather half signs a locktime tx to grandsons address,  grandson half signs completing the tx.

Outcome:
Coins are secure in address which both grandfather and grandson need to sign to create a new/alternative tx.  Grandson has a valid signed tx but it can't be included in a block until he turns 18 (well roughly it is based on block time).

The sad thing is that 429 GH/s hasn't made 0.33 BTC for a very long time.  It is more like 0.18 BTC today.  Not sure if it is incompetence or just scamming up more sales that made them ignore the fact that one day pool output is boosted by luck.

So it is 0.18 BTC per day for the next couple days but it will drop to 0.126 before they even deliver.  That would last for at most 11 days and then difficulty will go up at least another 30% so reward falls to 0.082.

TL/DR

No a lackluster 429 GH/s, delivered two months late and using just as much power as KNC ( remember when they bashed them) will deliver something 2 BTC in 21 days and that is probably 1/3 to 1/2 of what it will produce in its lifetime.

It would change your analysis to be that Bitcoin is a practical implementation of a system that may suffer from the Two Generals Problem.  Bitcoin exactly "solve" the problem.  The problem is considered to be unsolvable.  A solution would imply the system could never be compromised.  A 51% attack is a limitation of the Bitcoin implementation and thus the problem isn't solved.  What Bitcoin (or technically the consensus in ordering of valid transactions forced by miners using a proof of work) does is reduce the uncertainty on the permanence of a transaction by adding confirmations .... unless an attacker has >50% of the computing power.  However that doesn't mean the problem is solved only that the cost of an attack has been raised.

It is very likely that only computer science nerds would really care about the distinction but a false claim simply provides an easily defeated strawman.

Sorry I looked quickly and assumed the rawtx call provided the block hash as well as the block height.

Using blockchain.info API?
By looking for "mainchain" value in the rawblock RPC using the blockhash from step 1.

https://blockchain.info/rawblock/00000000000007d0f98d9edca880a6c124e25095712df8952e0439ac7409738a


With blockchain.info the internals of their API are a blackbox so I wouldn't want to assume that however you can explicitly confirm that by
a) getting the blockhash of the tx (rawtx)
b) checking that block is still in the main chain (rawblock)
c) computing the confirmations as latestblock_height - txblock_height  (latestblock)

Combined that allows you to verify that the tx is in a block, that the block is in the main chain and has the required number of confirmations.

If you have the ability to run bitcoind (can be run without server knowing the decryption passphrase or even better with a watching wallet copy) you can get the same information easier and without having to trust a third party.   You can use the transaction and block callback to be notified when a tx is included in a block and when a block has found.  By checking the status of the tx you can confirm it is in the main chain (orphaned tx will show 0 confirms).

If you want an easier option and can't run bitcoind, blockchain.info also has a receive payments API.  Understand this isn't zero-trust as payments will be sent to an address which blockchain.info has the private key for and then forwarded on to an address you designate.  This means in theory funds could be stolen if blockchain.info is hacked or "hacked".  It does however provide an easier higher level API and the potential loss is limited to payments that haven't yet been forwarded to you.  Depending on your transaction value and risk tolerance this might be acceptable.  Do your own due diligence I haven't used or researched this API.
https://blockchain.info/api/api_receive

We have very limited data to work with.  Velocity is the metric which balances money supply and GDP.
GDP = Velocity * Money Supply.

In plain english terms
(economic activity) = (avg number of times a $/BTC is involved in an economic transaction) * (money supply)


Change in velocity is why we have seen little inflation despite the fed printing an insane amount of cash.  If velocity remained constant we would have seen massive price inflation which would drive up at least the nominal GDP and force companies to spend their rapidly depreciating cash reserves.  Everyone has heard about how much the fed is printing (increase the money supply) however the other component is velocity and in this lackluster recovery velocity has collapsed.  More money is offset by less transactions per unit (dollar) and thus the economy remains sluggish.


BCT image proxy doesn't like the image so here is a direct link to the chart: http://research.stlouisfed.org/fred2/graph/?s[1][id]=M1V


In the Bitcoin world I don't know of any detailed analysis of GDP or velocity.  The nature of Bitcoin makes that difficulty,  although as Bitcoin gets larger I imagine economists will attempt to estimate the GDP just like they do other economies.  Even in "real" economies GDP, velocity, inflation, and even money supply are just estimates. 

One crude way would be to look at things like blockchain.info "estimated transaciton volume".  Blockchain attempts to remove the change from the transaction, but not all those transactions are "economic" and thus don't contribute to the "Bitcoin GDP".   Someone moving coins from one wallet they own to another wallet they own is not economic activity, anymore than moving $100 from your checking account to your savings account adds to the US economy.  Per blockchain.info there were 73 million BTC in transactions in 2013.  The average money supply for 2013 was 11.4 million BTC.  If we assume all blockchain tx were economic (not likely) and there were no economic off blockchain tx (not likely) that would be a velocity of ~6.5.  The hard part would be quantifying economic tx vs non-economic txs.

In comparison, national economies generally have a velocity of between 5 to 10 when looking at the M1.  Bitcoin is technically more like M0 but it probably displace the utility of M1 so that might be a better comparison.   Currency is a store of value, and a unit of account (used in transactions).  Bitcoin has been primarily the former but if it was used in transactions heavily I would imagine it would have a velocity on the high end of national currencies (i.e. velocity of 8 to 10 or higher).  On the other hand if BTC remains primarily a store of wealth and not a transactional currency it could have a very low velocity.  I don't know if anyone computes the velocity of gold (or more specifically gold bullion and coins) but my SWAG is that it is very low (<1).  A lot of gold once minted simply never changes hands for years or even decades.

TL/DR version:
We don't have enough information to estimate with any degree of accuracy the velocity, or GDP of the "Bitcoin economy".  Most national economies have a velocity (M1) of 5 to 10.  If we Bitcoin ends up similar that would mean supporting a $10T economy would mean a money supply valued at $1T to $2T.  On the other hand if Bitcoin was used more as a store of value then it would drive down velocity and increase the value of the money supply.

I wonder if the 1280 GH/s is a 2 module BJ (i.e. testing if power supply and cooling can handle the upgrade module).  That would put the hashrate of a module closer to 600 GH/s?  Meh.  I am going to log off.  Got to much work to do and the lack of info plus stats (of unknown origin) to watch will just burn up the whole day.

One sad fact is that 400 GH/s on Oct 20th is equal to 1,563 GH/s today.  So if HashFast was running 700 GH/s+ per module AND they decided to upgrade all Batch 1 customers to two modules, as amazing (and utterly unlikely) as that would be it would only be roughly as good as 400 GH/s back in Oct.  Kinda shows how deep the hole is now.

PS: If you have nothing else to do, rename the tabs from Sheet1,2,3 to something descriptive.   Nice spreadsheet BTW, I haven't verified the math or anything yet, but I always like using spreadsheets over blackbox website models.

You probably want to start you spreadsheet at 1.46 billion difficulty (10.5 PH/s) as we are 4 days from difficulty adjustment so HF batch 1 customers are not going to materially participate in that difficulty period.

It looks like it is starting @ 11 PH/s.  Either I need more coffee or I am losing my mind but I could have swore it showed 9 PH/s earlier.

Well once again $1T economy doesn't require $1T in cash.   i.e. the world economy $75T annually runs on ~$10T in cash (M0).

Money supply is a timeless value.  Values of economies (i.e. GDP) are timed value (i.e. usually $x per year).  You can't directly compare the two and they will never exactly equal each other unless velocity is 1.  Usually the same unit (dollar or Bitcoin) can be used in MORE THAN one transaction per year and thus the velocity is >1.

I am just saying this company has lied, mislead, backtracked, stealth changed TOS (in violation of law), falsely claimed customer prior to 15 AUG accepted a 31 DEC deadline, etc.

YOU REALLY THINK it is beyond the same company to drop it to two units and ship >1.2 TH/s?  Really?  I mean those customers would at least be getting more hashrate than they bought at roughly the timeline they were promised.  They still come out ahead of Batch 1 customers who at this point even a 800 GH/s rig + 400% of that in MPP delivered 1 Feb isn't enough to break even in BTC terms.

% increase = (next_est - current) / current * 100.

As pointed out it is rounded, it is an estimate, even 14% has a significant margin of error putting extra digits is just noise.


For the record the % increase of anything = (new - old) / old * 100