Just a quick comment on the actual fees (checked at blockchain.info) the average fee over the last 90 days is actually ~0.0003BTC/txn - so not too far behind the theoretical minimum of 0.00037BTC/txn.
I suppose, though, that it has more to do with old clients and fee settings (0.0005) than network wisdom ;) On 13/11/13, 12:52 , Michael Gronager wrote: > Last week I posted a writeup: "On the optimal block size and why > transaction fees are 8 times too low (or transactions 8 times too big)". > > Peter Todd made some nice additions to it including different pool sizes > into the numbers. > > However, it occurred to me that things can in fact be calculated even > simpler: The measured fork rate will mean out all the different pool > sizes and network latencies and will as such provide a simple number we > can use to estimate the minimum fee. Key assumption is that the latency > will depend on block size (# txns) and the fork rate will depend on latency. > > Using the formulas from last week: > > P_fork = t_propagate/t_blocks > > and: > > t_propagate = t_0 + alpha*S ~= alpha*S > > We get a measure for alpha as a function of the average fork rate and > average block size: > > alpha = P_fork*t_block/S > > Further, take the formula for the minimum fee: > > f > alpha*E_bounty/t_block > > And insert the formula for alpha: > > f > P_fork*E_bounty/S_average > > Luckily the fork frequency and the average block size are easily > measurable. blockchain.info keeps historical graphs of number of > orphaned blocks pr day - average over the last year is 1.5. Average > number of blocks per day over the last year is 169, which yields a > P_fork of ~1/113. Average block size in the same time is 134kBytes, > which yields a minimum fee: > > f > 0.00165XBT/kb or 0.00037XBT/txn > > So the 0.0001 is only 4 times too small. Further, let us look at the > trend over the last 12 months. Pieter Wuille claimed that there has been > several improvements over the last half year that would bring down the > latency, there has also been speculations regarding direct connections > between the major pools etc - lets see if this is indeed true. > > If you look instead of 360 days, only at the last 90 days the average > block size has been 131kBytes, and the fork rate has been ~1/118, which > results in a minimum fee of: > > f > 0.00162XBT/kb or 0.00037XBT/txn > > So a small improvement but not statistically important... > > Last question, recalling that optimal revenue block size is a function > of the txn-fee (from the last writeup) - lets see what fee it takes to > support a block size of 131kBytes: > > S = 1/2 * (t_block/alpha - E_bounty/f) > > S = 1/2 * (S/P_fork - E_bounty/f) > > f = E_bounty/[(1/P_fork-2)*S] = 0.00165XBT/kB > > So a 4 times increase is still sufficient for the current load. > > Anyway - the all important number is alpha, the network latency which we > expect to be dependent of various things such as interconnectivity, > bandwidths, software quality etc, where mainly the latter is within our > hands to bring down the fee. And you can actually setup the standard > client to choose a better fee, as all the parameters in the formula are > easily measured! > > ------------------------------------------------------------------------------ > DreamFactory - Open Source REST & JSON Services for HTML5 & Native Apps > OAuth, Users, Roles, SQL, NoSQL, BLOB Storage and External API Access > Free app hosting. Or install the open source package on any LAMP server. > Sign up and see examples for AngularJS, jQuery, Sencha Touch and Native! > http://pubads.g.doubleclick.net/gampad/clk?id=63469471&iu=/4140/ostg.clktrk > _______________________________________________ > Bitcoin-development mailing list > Bitcoin-development@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/bitcoin-development > ------------------------------------------------------------------------------ DreamFactory - Open Source REST & JSON Services for HTML5 & Native Apps OAuth, Users, Roles, SQL, NoSQL, BLOB Storage and External API Access Free app hosting. Or install the open source package on any LAMP server. Sign up and see examples for AngularJS, jQuery, Sencha Touch and Native! http://pubads.g.doubleclick.net/gampad/clk?id=63469471&iu=/4140/ostg.clktrk _______________________________________________ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
