Bitcoin Forum

hello,
how can i tell the bitcoin client it should not include a fee, even if i send very small amounts (0.0001) which are actually less than the fee itself.

i dont care how soon the transaction is included in a block.

thanks!

You can't.  Well you can hack the client to make it ignore the small transaction fee but most miners will exclude those transactions and anyone running "valid" clients will reject (not forward)  those transactions also.

The fee on small transactions it to prevent an attack called dust spam.  Imagine if small transactions were free.  The average transaction is about 0.5KB.  You could send 1 satoshi per transaction and take up 0.5 KB.  You could construct a miner which generates trillions of transactions per day.  This would result in GB per week of block chain bloat.  You could create terrabytes of permanent spam at a cost of a single BTC.   Not only will  it bloat the network it will cripple clients you spam (check litecoin thread in alt currency forum) as the client tries to compute best coins to send from millions of tiny transactions.

The fee on small transactions (less than 0.01 BTC) is a defense mechanism.  It isn't going away.  Without that rule malicious entities could cripple the network w/ an utter trivial amount of effort.

The easiest way to do this is probably through an online wallet. Bitcoin exchanges usually let you send bitcoins without paying fees.

Keep them in one output and keep them for a longtime, maybe you got a chance to send it with no fee.

That means that to send a 0,05 BTC i need a maturation of 2592 confirmations/ 150conf/day  = 18 DAYS

To send a 0,1 about 9 DAYS
To send a 0,5 about 2 days
To send 1 BTC about 0,9 days
To send 10+ BTC, almost immediately.

Technically the amount your sending doesn't matter it is the amount you are sending FROM.

So if you receive 0.1 BTC you need to wait 9 days to use it.
If you receive 0.5 BTC you need to wait 2 days to use it.
If you receive 1 BTC you need to wait about 0,9 days
If you receive 10+ BTC, you can send them right away.

If you send an amount from two addresses as the input then the "bitcoin days" from each input combine to meet the "free" threshold.

Also note there is ALWAYS a fee for very small transactions (<0.01 BTC) to avoid "dust spam" attack.  An infinite amount of time won't eliminate that fee.

I hear someone has released a hacked client, but the downside is most miners will ignore tiny transactions because there is no financial incentive to include it in the block. Whats worse is if your transaction never gets verified you could stand to lose your coins. Penny spamming as I've also heard it called is a more primitive version of potentially ddos-ing the bitcoin network, hence why miners will be more likely to ignore the transaction. Fees are healthy for the network, and the sender, doing otherwise is in no-one's interests.

I'd hardly call it hacked. Download the source code, change the portion responsible for tx fees, compile and viola!
Not much actual hacking involved.

Admittedly hacking might be too strong a word to describe the editing of one line of source code. Maybe we could just say his hand spasmed while he sneezed and mashed the keyboard, and viola, no tx fee bitcoin was born.  :D

i hope the fees can scale according to btv value and decimal point placing...

The problem is that the official client doesn't allow to join two or more transactions like Daily bitcoins.

then how do daily bitcoins do it? do they have a modified client?

What stops me from mining my own blocks with lots of 0.00000001 transactions in them to spam the blockchain ?

Thanks !

Hashing power and block size limit.

Hashing power costs time & money so does the spam fee.   Both methods ensure their is a significant cost to the attacker.