5
https://ripple.com/how-ripple-works/
While Ripple does not charge a typical fee for profit, each transaction does require a small portion of a ripple (equivalent to ~1/1000th of a cent) for security.
This seems to assume a certain conversion rate between Ripples (XRP) and real world money. How much in XRP is the TX fee?
7
The default fee for a transaction is 0.00001 XRP.
But the fee is not fixed. Quoting the wiki:
Transaction fees are adjusted based on two factors: base fee and load fee
base fee: long term fee adjustments Since transaction fees are paid in XRP and the price of XRP may change overtime, to keep the price of transactions affordable, Ripple uses an adjustable "base fee" to specify the cost of transactions.
load fee: short term fee adjustments The "load fee" can rise quickly to protect the network from attacks and keep the network functional under heavy load.
The fee schedule is changed using consensus, quoting. D.Schwartz:
A node can introduce a transaction to change the base fee. If a trust-weighted majority of nodes vote "yes" on the transaction, it will be incorporated into the ledger and the fee will be changed.
@ripper234 they are talking about software "server-side", I hope. – o0'. – 2013-02-13T22:12:09.370
Long term adjustments:
When we want to change the base fee or multiplier, we just release a new version of the software with a new base fee (or publish a new fee schedule). People can tweak that, but they probably won't. People might not upgrade, but they probably will– ripper234 – 2013-02-12T02:17:13.543