TWeaKLeGeND schreef op donderdag 26 januari 2012 @ 13:56:
Kain begrijpt het een en ander niet helemaal.
CP in de chain krijgen kan enkel versplinterd en alleen als je ENOOOOORM veel rekenkracht heb. Praktisch gezien zou alleen een heel grote pool dat kunnen en en dan slaat het alsnog nergens op want het zou alsnog veel te versplinterd zijn. Iemand die heel veel transacties aan maakt kan dit NIET.
Ook 9 transacties per seconden is zeker niet de limiet, de limiet is whatever degene die de block 'oplost' instelt. Je kan er zelf voor kiezen om 10 transacties mee te nemen in je blok die je oplost of een miljoen. Des te meer je er mee neemt des te meer transactiegelden je kan verdienen dus op den duur zou dat geen probleem moeten zijn.
Daarnaast is er wel degelijk anonimiteit omdat er al genoeg manieren zijn om
bitcoins te 'wassen'. Ik krijg 100 coins van 1 adres, en van 1000 andere mensen krijg ik ook een zooi coins, en ik stuur jou 5 coins 29 coins etc naar verschillende adressen vanuit andermans deposits tot je je 100 coins terug hebt. En alleen ik weet nog wie nou wie was, en dat hou ik als wasstraat niet bij uiteraard. Het hoeft overigens niet eens een wasstraat te zijn. Een gemiddelde exchange voldoet prima.
Dat de chain te groot word klopt maar word als t goed is redelijk opgelost
Tweaklegend, laat mij het even uitleggen. Eerst moeten we weten wat de block chain precies inhoudt. Nu ben ik geen programmeur, maar toch is deze materie vrij goed te begrijpen.
https://en.bitcoin.it/wiki/Block_chainA block chain is a transaction database shared by all nodes participating in a crypto-currency such as Bitcoin. A full copy of a currency's block chain contains every transaction ever executed in the currency. With this information, one can find out how much value belonged to each address at any point in history.
Every block contains a hash of the previous block. This has the effect of creating a chain of blocks from the genesis block to the current block. Each block is guaranteed to come after the previous block chronologically because the previous block's hash would otherwise not be known. Each block is also computationally impractical to modify once it has been in the chain for a while because every block after it would also have to be regenerated. These properties are what make double-spending of bitcoins very difficult. The block chain is the main innovation of Bitcoin.
Honest generators only build onto a block (by referencing it in blocks they create) if it is the latest block in the longest valid chain. "Length" is calculated as total combined difficulty of that chain, not number of blocks, though this distinction is only important in the context of a few potential attacks. A chain is valid if all of the blocks and transactions within it are valid, and only if it starts with the genesis block.
For any block on the chain, there is only one path to the genesis block. Coming from the genesis block, however, there can be forks. One-block forks are created from time to time when two blocks are created just a few seconds apart. When that happens, generating nodes build onto whichever one of the blocks they received first. Whichever block ends up being included in the next block becomes part of the main chain because that chain is longer. More serious forks have occurred after fixing bugs that required backward-incompatible changes.
Blocks in shorter chains (or invalid chains) are called "orphan blocks", and while they are stored, they are not used for anything. When a block becomes an orphan block, all of its valid transactions are re-added to the pool of queued transactions and will be included in another block. The 50 BTC reward for the orphan block will be lost, which is why a network-enforced 100-block maturation time for generations exists.
Because a block can only reference one previous block, it is impossible for two forked chains to merge.
It's possible to use the block chain algorithm for non-financial purposes: see Alternative Chains.
Kortom, in de block chain vinden we de volgende informatie:
Gewoonweg elke transactie die er ooit is uitgevoerd en ooit uitgevoerd zal worden met
Bitcoins.
Zeg maar de logs van een bank. Alleen dan als essentieel onderdeel van het systeem.
Wat is een transactie?
Een transactie is:
- zend adres
- ontvang adres
- bedrag
-eventueel transactie kost
Nu kun je zelf je eigen
bitcoin adressen kiezen. Dat kost weinig computer kracht.
Je kunt ook het bedrag dat je wilt versturen zelf kiezen. Dat kost helemaal geen computer kracht.
En dus met deze twee variabelen is het mogelijk om een boodschap te coderen in de vorm van een ontvang adres en een bedrag. Deze boodschap is heel erg kort natuurlijk. Maar door een transactie op te breken in meerdere transacties die je naar eigen adressen stuurt kun je feitelijk onbeperkt informatie in de chain krijgen. Die informatie bestaat dus uit adressen en bedragen die zo gekozen zijn dat die informatie daar dus ingecodeert is.
Volgens het volgende protocol
BTCmsg Protocol v1 (2011-09-18)
===============================
Each message is represented by multiple payment which is calculated by
the following algorithm:
1. Two first chars for message type ('01' for md5, '02' for ascii).
2. Then the message in hex (python binascii.hexlify).
3. Split the long string to groups of 4 hex digits.
4. Each group of 4 hex (e.g. 2 ascii letters from the message) is
represented by a payment in satoshi (maximum 0xffff=65535).
5. The service fee (composed of a fixed part and a variable part times
the amount of small payments required, minus the transaction fee),
can be seen within the first transaction.
Enjoy!
Kijk maar, op deze site kun je het zelf doen als je een halve BTC kunt missen en je bericht niet te lang is.
http://btcmsg.staticloud.com/#FAQ
Ook over die limiet van transacties per seconde. Die is er dus momenteel wel degelijk, maar kan vrij makkelijk worden aangepast in de software. (lichte clients, die niet de hele chain downloaden)
https://en.bitcoin.it/wiki/Talk:ScalabilityThere is one major point that the page overlooks: the limitation on block creation.
Block creation is limited to an average of one block every ten minutes. Furthermore, block size (which includes the transactions in the block) is limited to 1,000,000 bytes.
Each transaction requires 10 bytes, plus approximately 106 bytes for every input and approximately 69 bytes for every output. The exact size depends on the size of the public key, which I have not been able to confirm, but the keys in my wallet.dat seem to be about 65 bytes each.
If we assume that transactions average two inputs and two outputs, then the average transaction size will be about 350 bytes (note that the main page assumes an average of 1KB per transaction). If we further assume that the block size will, in practice, be limited to 500,000 bytes because the transaction fees increase as the block size increases, then that means there will be, on average, approximately 1430 transactions per block. That works out to an average of 2.5 transactions per second - well below the stated goal of at least 4,000 transactions per second.
Even if we assume only one input and one output per transaction, and that each block will contain the full 1,000,000 bytes, that still works out to only 5,405 transactions per block, or 9 transactions per second.
Unfortunately, this is not a limitation that can be overcome by simply increasing memory, or switching to a different ISP with more bandwidth. It is a built-in limitation, designed to deliberately slow down block creation. One solution is to somehow allow blocks to be freely created, while still keeping the rate of coin creation constant.
The bottom line is that, as it sits, this system is not scalable.
MAX_BLOCK_SIZE has always been planned to increase as needed. That limitation should be ignored. theymos 17:15, 4 March 2011 (GMT)
What Theymos said. Increasing MAX_BLOCK_SIZE will be done when "lightweight, header-only" client mode is done. Until then, block size has to be kept under control.--Gavin Andresen 00:19, 5 March 2011 (GMT)
I've updated the page with more discussion of this topic. --Mike March 5 2011
The thing with VISA or and credit card company is that there wouldn't be that many actual transactions. When I buy stuff with my credit card the vender doesn't get paid instantly. I pay my bill once a month and the vender gets all his transactions lumped into one payment from VISA (once a week, I think). Someone correct me if I'm wrong, but the number of real transfers of money would be much smaller. --Randomproof 17:29, 1 April 2011 (GMT)
Would also be nice to get some kind of an estimate on how much the crypto-operations could be accelerated with a GPU. Jojkaart 20:48, 13 June 2011 (GMT)
Shouldn't this (under Opimizations -> Network Structure): "Switching to DNS would give dramatically faster startup times that do not scale with the size of the network." read: "Switching to DNS would give dramatically faster startup times that do scale with the size of the network."? ie Remove the "not". --Tokoin 09:24, 21 July 2011 (GMT)
Ook kunnen BTC pas annoniem worden wanneer het een echt opzich zelf staande betaaleenheid word die niet de hele tijd moet worden omgewisseld naar dollars of euro's
https://en.bitcoin.it/wiki/AnonymityThe main problem is that every transaction is publicly logged. Anyone can see the flow of Bitcoins from address to address (see first image). Alone, this information can't identify anyone because the addresses are just random numbers. However, if any of the addresses in a transaction's past or future can be tied to an actual identity, it might be possible to work from that point and figure out who owns all of the other addresses. This identity information might come from network analysis, surveillance, or just Googling the address. The officially-encouraged practice of using a new address for every transaction is designed to make this attack more difficult.
The flow of Bitcoins from address to address is public.
The second image shows a simple example. Someone runs both a money exchanger and a site meant to trap people. When Mr. Doe buys from the exchanger and uses those same coins to buy something from the trap site, the attacker can prove that these two transactions were made by the same person. The block chain would show:
Finding an "identity anchor" allows you to ruin the anonymity of the system.
Import coins from address A. Send 100 to B. Authorized by (signature).
Import coins from address B. Send 100 to C. Authorized by (signature).
You can't change your "sending address"; Mr. Doe must send coins from the same address that he received them on: address B. The attacker knows for a fact that address B is Mr. Doe because the attacker received $5 from Mr. Doe's Paypal account and then sent 100 BTC to that very same address.
Another example: someone is scammed and posts the address they were using on the Bitcoin forum. It is possible to see which address they sent coins to. When coins are sent from this (the scammer's) address, the addresses that receive them can also be easily found and posted on the forum. In this way, all of these coins are marked as "dirty", potentially over an infinite number of future transactions. When some smart and honest person notices that his address is now listed, he can reveal who he received those coins from. The Bitcoin community can now break some legs, asking, "Who did you receive these coins from? What did you create this address for?" Eventually the original scammer will be found. Clearly, this becomes more difficult the more addresses that exist between the "target" and the "identity point".
You might be thinking that this attack is not feasible. But consider this case:
You live in China and want to buy a "real" newspaper for Bitcoins.
You join the Bitcoin forum and use your address as a signature. Since you are very helpful, you manage to get 30 BTC after a few months.
Unfortunately, you choose poorly in who you buy the newspaper from: you've chosen a government agent! Maybe you are under the mistaken impression that Bitcoin is perfectly anonymous.
The government agent looks at the block chain and Googles (or Baidus) every address in it. He finds your address in your signature on the Bitcoin forum. You've left enough personal information in your posts to be identified, so you are now scheduled to be "reeducated".
You need to protect yourself from both forward attacks (getting something that identifies you using coins that you got with methods that must remain secret, like the scammer example) and reverse attacks (getting something that must remain secret using coins that identify you, like the newspaper example).
Correlatie is dus erg gemakkelijk met BTC, juist door de openheid van het protocol.
)
:strip_exif()/u/350868/tacnayn%2520small.gif?f=community)
/u/182977/crop65f9e5220f264_cropped.png?f=community)
) BTC op 5 kopen, en nog een miljoen op 6 verkopen, en hij doet het automatisch :strip_exif()/u/79661/vorm.gif?f=community)
/u/158329/crop569e94642602d_cropped.png?f=community)
:strip_exif()/u/28308/phun.gif?f=community)
/u/26321/Globo.png?f=community)
:strip_icc():strip_exif()/u/9208/icon.jpg?f=community){kind=icon}
/u/265649/crop599d8670665b1_cropped.png?f=community)
/u/115763/Untitled-4.png?f=community)
/u/57732/GoT.PNG?f=community)
.:strip_icc():strip_exif()/u/388658/crop609926f05fa1c_cropped.jpg?f=community)
:strip_icc():strip_exif()/u/4103/Logo.jpg?f=community){kind=logo}
:strip_icc():strip_exif()/u/54401/braun_avatar_60x60.jpg?f=community){kind=avatar}
:strip_icc():strip_exif()/u/378821/images.jpg?f=community)
:strip_exif()/u/154471/crop5e09176a82484.gif?f=community)
/u/75021/avatar.png?f=community){kind=avatar}
Dit topic is gesloten.