On November 22, 2003 09:12 am, Edward J. Huff wrote: > On Fri, 2003-11-21 at 04:23, Ian Clarke wrote: > > Edward J. Huff wrote: > > > It seems to me that NGR can't possibly do certain things. > > > When the standard deviation exceeds the mean, you can't > > > even predict the sign of your random variable. > > > > The standard deviation exceeding the mean, if it does occur, isn't the > > fatal problem you think it is. NGR's data is likely to be extremely > > noisy, but provided that it is able to extract some generalization it > > should work, irrespective of the std dev. > > The question at issue is whether NGR can be used to distinguish > between nodes based on bandwidth, while the bandwidth available > to a transfer is allowed to vary randomly depending on requests > from other nodes. The issue is complicated: any node can > have its marginal available bandwidth fall near zero, and there > is a positive feedback loop through the estimators leading to > oscillation and inefficient use of resources.
This is a very very important point. The first NGR implementation did not use transfer rates in its estimators - maybe, exploitable as it was, it made more sense. It really depends on if transfer rate is predictable for a given node. Given that outbound bandwidth is more often than not the limiting constraint on a node I suspect that its not all that predictable... Ed > I think this is a valid and important question. Your response > does not address it. > > -- Ed Huff > > > _______________________________________________ > Devl mailing list > [EMAIL PROTECTED] > http://dodo.freenetproject.org/cgi-bin/mailman/listinfo/devl _______________________________________________ Devl mailing list [EMAIL PROTECTED] http://dodo.freenetproject.org/cgi-bin/mailman/listinfo/devl
