Stratum protocol is designed specifically for pool servers http://mining.bitcoin.cz/stratum-mining

I wasn't aware of this can you point to where I can read up on this?


If it pays a proper fee and is broadcast first the probability is high that this tx will get included in a block. As far as I'm aware, the probability is in your favour but there is still a chance, albeit small, that it will be double spent.

The problem here is that both tx would be valid. Both tx have valid inputs they are just sent to different receiving addresses. Whichever gets confirmed first becomes the "true" valid tx. As the inputs would now be spent the other tx becomes invalid and would never get confirmed. The order in which tx gets mined into a block depends on many variables. The time it was broadcast, how many other txs are waiting to be mined, the priority of the tx, etc..

One trick to double spend a 0 conf tx is to send the first tx with no or an extremely small fee so it stays at the back of the queue for tx waiting to be mined. This increases the probability that it won't get included in a block for a long time. Although this tx is broadcast first it will likely take a very long time to get included in a block hence a second tx can be made minutes after the first and propagate throughout the network. The second tx can be created paying a very high fee to jump in front of the queue of txs waiting to be mined and increasing the probability that it will be mined before the first tx.

Currently there is no way to have a valid 0 conf tx. You simply have to trust the sender won't double spend.

While the tx is broadcast as long as the tx is not confirmed the money is not owned by the receiver. The original owner is still in control of the money and can broadcast different txs with the same input. There is no guarantee the tx that sends the money to you will be confirmed before the other tx. Thus a double spend is possible for any tx that hasn't been confirmed.

0 conf tx is not safe because until the tx is confirmed no money has actually moved. Double spend attempts can be made at any point in time from the original tx broadcast until it is confirmed. Until the tx is confirmed the validity of the tx can change so the node can't validate a 0 conf tx.

+1

The minimum relay fee has always existed it was just set very low; so low that it allowed txs to be created that would cost more in fees to spend than the amount being sent. Unsurprisingly these txs tend to rarely be spent and unspent txs can't be pruned hence these tiny txs greatly contribute to blockchain bloat. Since the Bitcoin network is a shared resource some people would rather not relay these txs as they are uneconomical to spend and will likely just bloat the blockchain. Before the minrelayfee patch users who wanted to adjust relay fee rules would have to change the value in the source code and compile the program. Since the value of Bitcoin changes daily the minrelayfee needs to be adjusted often and requiring to recompile the program each time you want to do this is not practical. That's when this patch came in. The minrelayfee was changed from a compiled constant to an adjustable variable. At the time of the patches creation, 5400 Satoshis was the calculated minimum output that could be spent with a fee that would cost less than the output, so it was set as the default. You can freely adjust this by either starting Bitcoin with -minrelayfee=<minfee> or set minrelayfee=<minfee> in your conf file.

How can they stop printing at this point without crashing the markets?

I believe Bitcoin reference client only allows http/s requests.

EDIT: Also, any method that does not require a parameter, such as getinfo, your json request is not required to have "params":[]

In terms of monetary supply ( the amount of coins in existence ) Bitcoin is inflationary as new coins are being created and will continue to be made for quite a few years. When block reward drops to zero, in terms of monetary supply, Bitcoin will become neutral.

In terms of monetary value Bitcoin is very deflationary. Rate of adoption has outpaced monetary inflation causing Bitcoin to deflate substantially.

zero conf double spend works like this:

A buyer sends a payment to the merchant address.

Buyers address: 1aaa = 1BTC

This transaction contains no fee or a very small fee to ensure it takes a long time to get confirmed. As long as the transaction is not confirmed the buyer still owns the money.

The merchant will see that the transaction has been broadcast to the network and is waiting for confirmation. Since the merchant allows zero-conf transactions the buyer is free to leave with whatever the buyer "bought".

Merchant address 1mmm = 0BTC (1BTC waiting to be confirmed)

The buyer then creates another transaction using the same input address (1aaa) sending the money (1BTC) to a different address than that of the merchant. With this transaction a high fee is added thus increasing it's chances of being confirmed first.

If the new transaction gets confirmed first the old transaction is no longer valid as the address 1aaa no longer has 1BTC assigned to it and in so the network will never confirm it.

The buyer aka thief has just stolen 1BTC worth of goods from the merchant with incredible ease.

Mircea Popescu runs MPEX which is an exchange that ASICMiner refused to be listed on. He's been attacking AM ever since so anything he says should be taken with scepticism.

Try this https://github.com/slush0/stratum-mining

Cancelled

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

I am selling six (6) direct shares of ASICMiner at a fixed price of 4.7 BTC each.
No minimum quanity.
Payment must be made within TWO (2)  hours once you claim a certain amount to purchase. (Pay approptiate network fee so tx doesn't get stuck)
Claims for shares via pm are ok.
If share transfer is not made by next dividend day all dividends will be forwarded.
First come first serve.


Address: 1ASiCxNftoqwL91M1QDrcxq9uga3fXQNYg

Message: I, GoldenWings91 of bitcointalk.org, am selling 6 direct shares of ASICMiner.

Signature: HOcfgk54ohywmsl12xVO0LE1/TdDetsDHS0ZIujEeX32H9oN3uVMC7t/m3WuJNmBwoObvnMUBSdMdoisEPQQ6SI=


GoldenWings91
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Unfortunately I'm the buyer 

For items that have instant delivery I think six confirmations is overkill.

Bought one at 2.95 payment sent to 16Esrbw6SgJsNHoCiGNmRjmkx4ZobqaXqs

6aa87df7e45271b955c73a403c6ad9119cb8765c8de696eb8d4ae0988806a294

1 @ 2.95 if still available

1 @ 2.85

Timer removed. End time: 2013-06-20+13:05:00UTC

1 @ 2.8