Bitcoin Forum
January 18, 2019, 09:00:37 PM *
News: Latest Bitcoin Core release: 0.17.1 [Torrent]
 
  Home Help Search Login Register More  
  Show Posts
Pages: « 1 ... 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 [354] 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 »
7061  Bitcoin / Development & Technical Discussion / Re: Taking the 'pseudo' out of 'anonymous' on: November 11, 2010, 08:28:32 PM
- A uses the proxy API to say "I want to send X to B".
- A receives an address Y
- A sends some value to Y, could be more, could be less multiple times
- Once enough is transfered, proxy sends to one or two new addresses internally, breaking the value in pieces with a little randomization along the way
- proxy sends X to B
- proxy sends change to A
--- and the tricky part
- after enough confirmations on both to A and to B transfers are received, proxy deletes the addresses from the wallet

This prevents casual spying, but there would still be a connection between A and B. If an attacker was really serious about seeing where A was spending his coins, they would follow the transactions down to the the first known identity. If this is B, then they can force him to reveal who he received coins from at that address. They then either find A or find a closer person who they can question.

This simple mixing can be done without a third-party by creating some new addresses on your machine and doing the mixing yourself.

If the proxy has many customers and is careful not to give coins back to the customer who sent them, then you have a true "Bitcoin proxy" that can't be bypassed without compromising the proxy.

Relevant:
http://bitcointalk.org/index.php?topic=241.0
http://www.bitcoin.org/wiki/doku.php?id=anonymity
7062  Bitcoin / Project Development / Re: Donating to the Freenet Project on: November 11, 2010, 08:09:40 PM
BTW, is storing a file on FreeNet reliable ?  I mean, as I understand it, FreeNet is P2P.  This means that a file is there only if people use it.  If I am the only one who need a file, isn't it likely to disappear from the network if I don't consult it regulary ?

It might stay for a week or two (unpredictable). It's certainly not a good destination for backup.
7063  Bitcoin / Bitcoin Discussion / Re: The State vs. Bitcoin on: November 11, 2010, 07:53:01 PM
I almost fell out of my chair when I imagined law enforcement each having Block Explorer running as their home page.

This is exactly the effect I intended! Smiley Once people understand how attacks would be performed, they can learn how to use Bitcoin safely.

Maybe Bitcoin could implement a Tor system for the transactions in itself, so buyer and seller never interact directly. I will confess I have not master the bitcoin protocol (I am lazy) so can anyone tell me if it makes sense?

Tor doesn't ensure anonymity, though it is required for anonymity. The problem is not in the network layer; the problem is that every transaction is recorded in the block chain (and there's no known way to avoid this in a decentralized way). See http://www.bitcoin.org/wiki/doku.php?id=anonymity .

Maybe Open Transactions will someday be used for Bitcoin-backed bank notes. Open Transactions is perfectly anonymous, but centralized.
7064  Bitcoin / Project Development / Re: Donating to the Freenet Project on: November 11, 2010, 07:39:33 PM
CHK ?

A CHK is the main type of Freenet URI. The file is already encrypted on the network, and the key is in the CHK, so if you keep the CHK secret the wallet can't be recovered.
7065  Bitcoin / Development & Technical Discussion / Re: [PATCH] implement getblock RPC command on: November 11, 2010, 05:03:09 PM
I think that this can be fixed by changing this:

Code:
if (pindex->nHeight == height) {

to this:

Code:
if (pindex->nHeight == height && pindex->IsInMainChain()) {

jgarzik: I don't have any orphan blocks right now, so can you test this on your block 90539 and compare it to the real one?
7066  Bitcoin / Bitcoin Discussion / Re: Total Bitcoins Over Time on: November 11, 2010, 02:59:18 PM
There are currently 4.56 million bitcoins. Looking at the graph, it seems to be very close to the current reality.

My old prediction said there'd by 4.02 million now, so we are a bit ahead.
7067  Bitcoin / Bitcoin Technical Support / Re: Can wallet.dat be used by several miners on different computers? on: November 11, 2010, 02:45:09 PM
You could modify Bitcoin so that they all use the same key for generation transactions.
7068  Bitcoin / Project Development / Re: Donating to the Freenet Project on: November 11, 2010, 02:42:15 PM
Upload a backup of your wallet.dat (encrypt it first).

Encryption isn't necessary if you keep the CHK secret.
7069  Bitcoin / Bitcoin Discussion / Re: Total Bitcoins Over Time on: November 11, 2010, 02:34:55 PM
The bitcoins earned per block ("subsidy") will halve at 210,000 blocks, regardless of the network's CPU speed. The problem is in determining how fast we'll get to that point.

The generation difficulty adjustment tries to keep the rate of blocks per hour constant, so the chart won't be far off. The timing of the chart might be a little late because the CPU speed of the network is constantly growing, so blocks are currently being produced more frequently than they should be. Once growth stops in a few years, it'll be possible to predict the times of future subsidy adjustments more accurately.

So the chart is not affected per se by total CPU speed, but by growth/reduction in that speed.
7070  Bitcoin / Development & Technical Discussion / Re: Easier generation without chainging the protocol... on: November 11, 2010, 02:40:38 AM
Increasing the rate of block generation would increase the number of chain forks, which makes the system less reliable and easier to attack. Focus is shifted from CPU power to network power. 10 minutes already causes a significant number of chain forks:

Quote
        // Don't show generated coin until confirmed by at least one block after it
        // so we don't get the user's hopes up until it looks like it's probably accepted.
        //
        // It is not an error when generated blocks are not accepted.  By design,
        // some percentage of blocks, like 10% or more, will end up not accepted.
        // This is the normal mechanism by which the network copes with latency.
        //
        // We display regular transactions right away before any confirmation
        // because they can always get into some block eventually.  Generated coins
        // are special because if their block is not accepted, they are not valid.
7071  Bitcoin / Development & Technical Discussion / Re: [PATCH] implement getblock RPC command on: November 11, 2010, 02:36:39 AM
ArtForz figured out that this is caused because getblock is showing an orphan block at that position instead of the real block. Deleting the block database files fixes it because you won't re-download orphan blocks.
7072  Bitcoin / Bitcoin Discussion / Re: Bitcoin Block Explorer on: November 10, 2010, 11:21:27 PM
I'm suggesting you do this, but it just occurred to me that you could add the ability to put notes on everything wiki style.

Comments about addresses especially. This could be useful for sharing information while investigating scams and such. Plus it would just be fun to sift through all the labels people put on stuff, like I was wondering how much the mtgox donation addy got, I think I found it from my transaction history, but I don't know for sure, or if he had a different one up previously, etc.

I was thinking about that, too, but it seems to me that any comments would get lost in the gigantic sea of pages. If I see a lot of "look at this cool thing on BBE!" posts on the forum, I will implement this.
7073  Bitcoin / Bitcoin Discussion / Re: Pros and cons of using new Bitcoin addresses for each transaction? on: November 10, 2010, 10:40:57 PM
An address has 33 significant characters, each of which has 62 possible values (10 numbers, 26 uppercase letters, 26 lowercase).
So you have 62 * 62 * ... * 62 possibilities (33 times).

Actually, now that I remember, it's 58 (uppercase i and lowercase L are not included because they look too similar, same for zero and uppercase o).

So there are 58^33 possibles values, which is slightly more than 10^58. Still high, but not quite as high as 10^92.

As ByteCoin already explained earlier in the topic, an address contains a non-data check code and version number. There are actually "only" 160 bits of randomness in each address: 2^160, or 1.46x10^48 possible addresses.

Addresses can also be 25-34 characters in length, depending on how numerically large the hash160+check code is (the larger it is, the more base58 characters required).
7074  Bitcoin / Bitcoin Discussion / Re: Open Transactions: untraceable digital cash on: November 10, 2010, 06:59:13 PM
Did anybody ping satoshi on this thread?

Open Transactions must be centralized, so it doesn't fulfill the goal of Bitcoin.
7075  Other / Off-topic / Re: SMF Question: What does the posting option "Return to this topic" do? on: November 10, 2010, 06:17:41 PM
http://bitcointalk.org/index.php?action=help;page=post#return
7076  Bitcoin / Bitcoin Discussion / Re: Bitcoin Block Explorer on: November 10, 2010, 04:27:31 PM
Thanks theymos, this was much needed. I sent you some bitcoins for your efforts Smiley

Will you be releasing the source? Or maybe just giving access to your processed data in a nice format? I'd like to try to make some GraphViz charts (for example, being able to graph all transactions to/from a certain address given a maximum depth - that sort of thing).

Thanks!

I will not release the source unless there is a lot of demand for it. It is written specifically for BBE, and it would probably not be very useful for learning about Bitcoin or making similar things. For example, my getblock->SQL script does a bunch of unnecessary and redundant work in order to create database tables that can be efficiently accessed by BBE.

Here are the PHP base58/address functions that I wrote for this project, though:
http://pastebin.com/vmRQC7ha

I will offer data (maybe for a small fee). What format would be useful?
7077  Bitcoin / Bitcoin Discussion / Re: Bitcoin Block Explorer on: November 10, 2010, 03:52:15 AM
I made it so inputs/outputs are always listed in the order they appear in blocks.

So are listed balances correct, but the faucet is off because it uses/used multiple addresses or something? Can you elaborate on the change issue you mentioned?

Most of the faucet's balance is stored in addresses created when sending change. Here you can see that it sent 0.5 to someone, and then sent back to a new address - this new address does the same thing, and the new address from that transaction does the same thing, etc. You can also see the ordering randomization from this chain of transactions.
7078  Bitcoin / Bitcoin Discussion / Re: Bitcoin Block Explorer on: November 10, 2010, 03:15:38 AM
Thanks for the donation and nice comments!

I just noticed a bug, which I won't be able to fix today: the type of transaction listed after "Sent" or "Received" on address pages is wrong.

A question. When you send coins and get change both addresses are listed, are they listed in the same order every time? Is it random, or alphabetical...

The order is randomized when sent. BBE shows them in an unspecified order on address and block pages (I might change this), but it preserves the block's ordering on transaction pages.
7079  Bitcoin / Bitcoin Discussion / Bitcoin Block Explorer on: November 10, 2010, 02:33:29 AM
I created a site that lets you view detailed information about Bitcoin blocks, addresses, and transactions.

http://theymos.ath.cx:64150/bbe/

This data is all gotten from the block chain. It has always been possible to get this data, but you had to patch Bitcoin with getblock or use the clunky -printblock switch in Bitcoin, and then you had to search through miles of data to get what you wanted. Now everything is available in a clickable and easily-searchable format.

Some highlights:

- The genesis block, which is included with every version of Bitcoin. If you click the only transaction in this block (the generation transaction), you will see that the "genesis coins" have not yet been spent ("not yet redeemed" in "outputs").

- 198.99 BTC has been donated to the EFF since a Bitcoin address was added to their site. (As of this writing. Hopefully more will be added.)

- Bitcoin Faucet has sent and received a ton of transactions. Because of the way change works in Bitcoin, the total balance on this page is not the actual Faucet balance, and this page does not represent all Faucet transactions.

- Surprisingly, the three transactions with unknown "to" addresses in this block are the only non-standard transactions in the block chain. The repeated OP_CHECKSIG commands cause everyone downloading the block chain to do extra cryptography -- the bug that allowed this transaction to be included is now fixed, but these old transactions still exist.

- 50 BTC has already been donated to BBE, even though I hadn't officially announced it yet. Thanks! If you click on the transaction and follow it back one transaction, you can see that the coin used to donate to me was a generation from January 2010.

- Following one of the addresses used by a scammer (according to BuyBitcoins), you can get all of the addresses that ever received coins from this address:
1PwQfGPUFfuqqsmqpg8GegKziMV5Y3qfyr
18oCRAYcQEFbgm7nUCnJ7CqfgYxrhj9Des
16Fdg74JrkWogNDLDM8FJS1k5QrKAouBts
12cPg8VXSL3R3GnphKbpabC14S1sZXbsmU
19w4JEHG2fjVkEeheLSQNTZmmj81KvSzK7
If you own one of these addresses, then maybe you can identify this scammer. This list is only going one level deep -- it's also possible to find a list of every address that received "stolen coins" from the original address, possibly through multiple levels.

I hope BBE will be useful and informative. One of my main motivations for creating it was to inform people of the exact limitations of Bitcoin's anonymity -- it's possible to remain anonymous, but only if you're careful.
7080  Bitcoin / Bitcoin Discussion / Re: Bitcoin Low Latency Incentive on: November 10, 2010, 01:41:37 AM
I have not seen this actually used for IP networks ever, the only time I've seen it used is back in the UUCP days for routing mail along a specific path.

Does anyone know if this is actually used anymore, or indeed can actually be used anymore? I suspect it is entirely defunct.

Loose and strict source routing are part of the IP specification. The IP header only has room for nine source routing addresses, though, which limits its usefulness. My man page for traceroute says (-g does loose source routing - no option for strict in my version):
Quote
-g gateway
Tells traceroute to add an IP source routing option to the out-going packet that tells the network to route the packet through the specified gateway. Not very useful, because most routers have disabled source routing for security reasons.

IPv6 used to have a similar feature, but it was removed.
Pages: « 1 ... 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 [354] 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 »
Bitcointalk.org is not available or authorized for sale. Do not believe any fake listings.
Sponsored by , a Bitcoin-accepting VPN.
Powered by MySQL Powered by PHP Powered by SMF 1.1.19 | SMF © 2006-2009, Simple Machines Valid XHTML 1.0! Valid CSS!