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Topic
Board Project Development
Re: Concern about hiring programmers for project. Advice?
by
bcforum
on 18/10/2011, 07:28:45 UTC
This is a really bad idea. Reputable professionals won't sign your NDA.

Why wouldn't a "reputable" professional sign the NDA?

Post
Topic
Board Mining
Re: Should I Be Traffic Shaping Port 8332 On My Dedicated Mining Router?
by
bcforum
on 09/10/2011, 23:48:53 UTC
Mining uses so little bandwidth I doubt it makes much of a difference but it can't hurt.

Mining isn't a problem, but the bitcoin client will saturate the outbound link (when uploading block chain to other clients) causing your pool miners to have connection problems.
Post
Topic
Board Beginners & Help
Re: Bitcoin Price Predictions
by
bcforum
on 09/10/2011, 19:06:53 UTC
unless they can somehow remove the 21mil limitation it will be kept to a select few...... now if their was 100mil in circulation things would be up on price.

They can easily multiple the number of coins by shifting the decimal place in the bitcoin client. 1 coin magically becomes 2!
Post
Topic
Board Bitcoin Discussion
Re: Guy on twitter claims he is working on hash method without brute force.
by
bcforum
on 09/10/2011, 19:05:50 UTC

During the era of CPU mining is wasn't unusual for miners to search only the lower part of the nonce range. since a full 2^32 search would take too much time. I haven't analyzed the data yet, but I suspect there are more low nonces than high ones.

Code:
$ cat nonce.lst  | grep "^0" | wc
  47080   94160  753333
$ cat nonce.lst  | grep "^1" | wc
  12470   24940  201587
$ cat nonce.lst  | grep "^2" | wc
   7442   14884  121209
$ cat nonce.lst  | grep "^3" | wc
   6314   12628  103299
$ cat nonce.lst  | grep "^4" | wc
   6106   12212   99962
$ cat nonce.lst  | grep "^5" | wc
   6127   12254  100398
$ cat nonce.lst  | grep "^6" | wc
   6086   12172   99695
$ cat nonce.lst  | grep "^7" | wc
   6077   12154   99477
$ cat nonce.lst  | grep "^8" | wc
   5895   11790   96551
$ cat nonce.lst  | grep "^9" | wc
   5908   11816   96690
$ cat nonce.lst  | grep "^a" | wc
   5833   11666   95570
$ cat nonce.lst  | grep "^b" | wc
   5899   11798   96666
$ cat nonce.lst  | grep "^c" | wc
   5994   11988   98234
$ cat nonce.lst  | grep "^d" | wc
   5898   11796   96569
$ cat nonce.lst  | grep "^e" | wc
   5872   11744   96231
$ cat nonce.lst  | grep "^f" | wc
   5815   11630   95291

For those of you that don't speak Unix, the above data shows I'm correct.
Post
Topic
Board Mining
Re: Should I Be Traffic Shaping Port 8332 On My Dedicated Mining Router?
by
bcforum
on 09/10/2011, 17:37:19 UTC
I have a DIR-655 Dlink wireless router I am using to supply internet access to 4 mining rigs each running about 5 cards.

I am having troubles connecting to deepbit.net occasionally using phoenix miner. I will mine great for a few hours/days but eventually some of the cards go offline and never come back on. This is always preceeded by a "deepbit.net unavailable" type message...

Would It make sense to optimize port 8332 or my router in the QOS/traffic shaping section?

I have read phoenix miner is no good at re-connecting from downed internet connections (I am using the version available in linuxcoin v0.2a, not sure what version of phoenix it is, perhaps I have to upgrade?)

Any suggestions are appreciated!

Necromancy FTW!!!

I've noticed my bitcoin client will saturate the outgoing link a couple times a day which causes timeout errors from the miners, and I've been trying to get traffic shaping to work with the Tomato firmware on my Linksys router. Does anyone have any suggestions?
Post
Topic
Board Beginners & Help
Re: Bitcoin Price Predictions
by
bcforum
on 09/10/2011, 14:05:55 UTC
Here's a good question for bitcoin price:  what happens next year at block 210000?

The price will go up.

Right now there are a bunch of professional miners who are attempting to make a living from mining bitcoins. Every month (when their bills come due) they sell a bunch of coins and drive the price down. When the difficulty vs. payout doubles, their income will halve and many will shutdown because they can't cover their costs anymore. You'll also see a flood of used mining rigs and GPUs hit ebay at that time.
The difficulty will gradually trickle down until only the most profitable miners and the enthusiasts are still mining.
Post
Topic
Board Project Development
Re: New Idea: Need some Feedback Please :)
by
bcforum
on 09/10/2011, 13:55:11 UTC

Is this a credit or debit card?

Credit card: lots of risk on both sides, amount I own is dependent on the exchange rate when you send bill. Your payment is dependent on exchange rate when you receive coins.
Debit card: risk depends on currency the card stores
Post
Topic
Board Project Development
Re: Concern about hiring programmers for project. Advice?
by
bcforum
on 09/10/2011, 13:50:42 UTC
I've got a unique project that I am working on that I've received some good feedback on, and I think will be widely used by certain demographics. However, some of the coding required for it is above my skill level. I could probably take the time to learn the language required to get it going but 1) it may not be as effectively implemented as someone with a higher skill level and 2) I'd like to get it off the ground sooner rather than later. So my concern is, how do I go about hiring a programmer for this work and trust that he won't simply take my idea and create his own version of it?

1) Write a specification which describes the project, including a reasonable description of the completion state. Bug-free is not a valid description.
Hire a lawyer to write a work contract and NDA (non-disclosure agreement).
Require the programmer to sign the NDA before you discuss the project. You can give a general sense (a web based system to do e-Commerce). A professional will sign without any complaint. Look for a different person if they give you any grief at all regarding the NDA. The NDA is your primary means of protecting yourself if they share your idea with anyone else.
Once you have the signed NDA in hand, give them the specification and make sure they understand it.
Get a quote on how long it will take and how much it will cost. If it is too expensive, find a different programmer. You might have to offer a share of the company to get the upfront cost down.
After you reach an agreement sign the contract with them. They can now sue you if you don't pay, and you can sue them if they don't complete the work.

3) Profit
Post
Topic
Board Bitcoin Discussion
Re: Guy on twitter claims he is working on hash method without brute force.
by
bcforum
on 07/10/2011, 02:59:43 UTC

For those of you keeping track, the following nonces are UBER SPECIAL:

Code:
04111a63
a7900e03
bb971f16

Can you guess why?
Post
Topic
Board Bitcoin Discussion
Re: Why is bitcoin proof of work parallelizable ?
by
bcforum
on 06/10/2011, 16:58:06 UTC
Very interesting discussion in this thread. I think I understand both the goals which Forp tries to achieve and the reasons for it.

One possibility to include badly parallelizing serialization into the Bitcoin would be to request that each step of PoW depends on the previous one.

Example of the idea (unusable for real usage):

To find a block (PoW):

1. Set initial hash H0 = SHA256([ block header ] )
2. Perform following serial steps:
3. Let Hn+1 = SHA256([Hn | Kn]), where each Kn is randomly chosen
4. When Hn is lower than difficulty, stop, solution is found, store nonce and all Kn ;-)

By [a | b] I mean concatenation of the blocks a and b into single message.

Thus, even if I own 4 computers, they will compete each against other and will not help me to find more blocks in given time frame.

Of course, there is big flaw in the above - verification of block requires the same time as took to find the block, plus one needs to store all Kn chosen. But its an idea that came up. Feel free to improve on it Smiley.

If you have 4 computers you can test 4 different Kn at a time -> 4 times the chance of finding a winning nonce.
Post
Topic
Board Bitcoin Discussion
Re: RENCI Supercomputer mining bitcoins?
by
bcforum
on 06/10/2011, 16:48:18 UTC

From their website they have several computing clusters http://www.renci.org/resources/computing. One of these has Nvidia Tesla GPU's which could be suitable for mining. The question is could someone be mining on their clusters and would they have have enough hash rate to have any effect on the network?


Yes, they could use the Tesla's for mining and someone probably did. After exchanging their bitcoins for cash they realized they would never pay off the expenses of running the supercomputer to mine and gave up.
Post
Topic
Board Mining
Re: Half million tries
by
bcforum
on 06/10/2011, 16:44:16 UTC
I'm solo mining and have hit 500,000, should i stop or keep going.  I was hoping to find one block solo mining just to be able to do it.  Im kinda frustrated at this point, but wondering if I have come to far to stop.  I know its like a lottery and each hash is its own chance of winning.  I'm currently at 3.0 ghash/s. Any comments.  Thanks.



I'm solo mining at 2GH/s and got nothing for two weeks. Then three over the weekend. Then nothing for 1.5 weeks (and counting)

In the long run you will make more money solo mining than pool mining. With a pool you lose transaction fees, rejected shares, idle miner time, and in some cases pay a fee to the operator.
Post
Topic
Board Mining
Re: Spartan6-LX150 board for $250 -- gauging interest for mid-Oct ship date
by
bcforum
on 25/09/2011, 15:41:42 UTC
I currently mine with my own HDL code -- which is not performing very well yet (!).  I have deliberately not looked at or downloaded fpgaminer's code in order to avoid being the target of accusations.

The legal definition of 'clean room software' is much more flexible than most people assume.

You can look at fpgaminer's (or any other available) design.
You can write detailed specifications based on the design while looking at it. You have to be careful not to include any copyrighted material in the specification (IE code snippets.)
The same person can use the specifications to develop a new design.

The only limitation is: you cannot reference the original code while developing the new code.


For everyone else, the LX150 isn't supported by the free version of the Xilinx tools. You'll have to buy the full version ($5K?) to develop for this board.
Post
Topic
Board Mining software (miners)
Re: [MINER] Phoenix - New efficient, fast, modular miner **BFI_INT support!**
by
bcforum
on 24/09/2011, 15:05:46 UTC
I just add a new VGA to a rig, now it has 5 vga.
When i try to start mining i have this problem:

X Error of failed request:  BadValue (integer parameter out of range for operation)
  Major opcode of failed request:  141 (ATIFGLEXTENSION)
  Minor opcode of failed request:  67 ()
  Value in failed request:  0x17
  Serial number of failed request:  18
  Current serial number in output stream:  18

dont know why....

Did you make a new Xorg.conf and reboot?
Post
Topic
Board Development & Technical Discussion
Re: Timejacking & Bitcoin
by
bcforum
on 22/09/2011, 14:17:16 UTC
With regards to the suggestions of integrating NTP into the bitcoin client, I think it is a bad idea.  The bitcoin client is simply not an appropriate place to put timekeeping software.

If I were emperor, I would make the client turn red if it thinks the local clock is off by more than 5 seconds from what the peers report, and refuse to run if off by more than 30 seconds.

Code:
Added time data, samples 405, offset +0 (+0 minutes)
-86493  -86018  -3606  -277  -168  -121  -100  -98  -87  -80  -79  -75  -74  -60  -56  -54  -53  -52  -36  -36  -36  -32  -31  -31  -30  -29  -27  -26  -26  -26  -24  -24  -23  -22  -19  -18  -18  -16  -16  -16  -15  -14  -14  -14  -14  -13  -13  -13  -12  -12  -11  -11  -11  -11  -11  -11  -10  -10  -10  -10  -9  -9  -9  -8  -8  -8  -8  -8  -8  -7  -7  -7  -7  -6  -6  -6  -6  -6  -6  -6  -6  -6  -6  -6  -6  -5  -5  -5  -5  -5  -5  -5  -5  -5  -5  -5  -5  -5  -5  -5  -5  -5  -5  -4  -4  -4  -4  -4  -4  -4  -4  -4  -4  -4  -4  -4  -4  -4  -4  -4  -4  -4  -4  -4  -4  -4  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -3  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -2  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  -1  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +0  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +1  +2  +2  +2  +2  +2  +2  +2  +2  +2  +2  +2  +3  +3  +3  +3  +3  +3  +3  +3  +3  +4  +4  +4  +4  +4  +4  +4  +4  +4  +4  +5  +5  +5  +5  +5  +5  +5  +6  +6  +6  +7  +7  +7  +7  +7  +8  +8  +8  +9  +9  +9  +9  +9  +11  +11  +13  +14  +14  +15  +19  +20  +20  +22  +23  +26  +26  +37  +43  +44  +45  +50  +59  +85  +87  +93  +96  +124  +126  +169  +189  +284  +311  +3596  +3687  +7217  +83428  +5654326511063269263  +5790349588594885090 

Some of these systems need a color worse than red, but I think 5 seconds is too tight. 1 minute would throw a blanket of most of them, and a popup message to the rest pointing them to instruction on how to fix their clock would suffice for the rest.
It's interesting to note three are 1 hour, one is 2 hours, and three are ~24 hours off. I wonder if that is deliberate (run your computer in a different timezone so you now when to skype your grandkids), or a curious mistake.

Post
Topic
Board Development & Technical Discussion
Re: [Request] Bandwidth limits
by
bcforum
on 22/09/2011, 14:02:41 UTC

I am mining solo, and I want to be a core node of the peer-to-peer network (to improve propagation of my mined blocks.) Limiting the rate of bulk uploads to 50% of my outgoing connection solves that problem. Limiting the download rate is only for symmetry.
Post
Topic
Board Development & Technical Discussion
Re: Bit-error in Block 108009, Tx 23 ?
by
bcforum
on 22/09/2011, 04:22:49 UTC
would putting your hardware inside a properly grounded faraday cage reduce the number of errors? alon

Purchasing a server from a respected company instead of a desktop computer from e-machines would go a long way to reduce the number of errors. Bit rot is a common problem on desktop computers, particularly if they are overclocked or you are pushing the memory to it's limit. Just because it 'seems' stable you don't have any guarantee random memory errors aren't occurring.
Post
Topic
Board Development & Technical Discussion
Topic OP
[Request] Bandwidth limits
by
bcforum
on 22/09/2011, 04:09:13 UTC

I would like to limit the bandwidth usage of the client. I have a bitcoin daemon running all the time to support mining, but on occasion it uploads large chunks of data to other clients. This causes my latency to spike in online games which is irritating. A pair of programmable bandwidth caps (upload/download) would lessen the impact of distributing the block chain during gaming sessions.
Post
Topic
Board Development & Technical Discussion
Re: Preparing for wx --> qt switch
by
bcforum
on 22/09/2011, 03:51:33 UTC
As I understand the problem, in order to separate the wallet/GUI from the block chain you need to draw a line between them.

The wallet has:
    High security
    The macro transaction as defined by the user (number of coins, dst address, maximum tx fee)
    All the valid addresses associated with the signing key
    The signing key
The wallet needs:
    An exact list of the micro transactions required to execute the macro transaction
------------------------------------------------------------------------------------------------------------------------------
The block handler has:
    Internet connectivity
    A list of all addresses in the universe and how many coins are associated with each of them
The block handler needs:
    A signed list of micro transactions to be included into the block chain


So, it seems like the following steps are required to perform a send transaction:

1) User inputs the number of coins, destination address and maximum transaction fee (optionally the addresses to take the coins from)
2) Wallet requests number of coins in each address (from block handler) starting with the oldest until sufficient coins are available to complete transaction
3) Wallet builds micro transaction list, calculates TX fee, and prompts user if calculated fee is too high
4) Wallet sends signed micro transaction list to block handler
5) Block handler validates transactions and reports back to user success/failure. Note that the block handler does this for transactions from the internet anyway.
6) If valid (block chain hasn't reorg'd) transaction is broadcast to world

Does this solve your inversion of control problem? I believe it addresses my security concerns regarding the signing key being attached directly to the internet. There is an issue with the wallet needing to request all coins in all addresses in order to update the current balance. I prefer the extra workload this incurs over having all the wallet addresses resident in the block handler where they could potentially be stolen.

PS a better link http://www.wired.com/medtech/genetics/magazine/17-05/ff_protein?currentPage=all
Post
Topic
Board Development & Technical Discussion
Re: Preparing for wx --> qt switch
by
bcforum
on 21/09/2011, 23:10:03 UTC
I have a semi-constructive proposal. There has been a lot of whining and quarter-baked proposals floating about changes and improvements to the Satoshi client. It is hard to judge whether these proposals are made by incompetent programmers or just programmers that haven't thoroughly reviewed the code and its architecture.

To save the further anguish I propose that anyone who wants to be treated seriously should explain how his proposed improvement will deal with the following pseudo-code (from wallet.cpp & ui.cpp):

CWallet::SendMoney() {
    grab_the_wallet_lock();
    solve_inverted_knapsack_problem_to_select_the_best_coin_subset();
    fee = compute_the_required_transaction_fee();
    yesno = ::ThreadSafeAskFee(fee);
    commit_transaction_and_release_lock(yesno);
}

Basically, show us that you know how to solve the inversion of control problem that is posed by this code. For extra credit, show us that your modification will deal properly with chain reorganization while waiting inside the UI for the user to accept the fee.

If you don't know how to solve those problems please send your proposal to /dev/null or nul:, as the case may be.

I think John Smith did a feat of software engineering comparable to doing a successful face transplant on a Frankenstein.

An interesting problem, perhaps we could crowdsource a solution.

Oh wait, nobody without a masters in software engineering is qualified to make suggestions on the architecture of the client.

http://www.tomsguide.com/us/video-game-foldit-research-aids-virus-folding,news-12584.html

You might be interested to note most of the gamers didn't have degrees in molecular biology.