Excerpts from Paul Jakma on Thu, Jan 22, 2009 01:12:40PM +0000: > On Wed, 21 Jan 2009, David Conrad wrote: > >> Paul, >> >>> I assumed there was an implied ", to a significant enough extent for >>> it to matter" at the end of the sentence I quoted. >> >> What meets your requirement of enough "to matter"? Depending on >> deployment scenario, a tunnel-router-based solution could cover >> thousands of hosts or more. Is that enough to matter? > > It's going to be subjective to a point, but determining "to matter" > would involve comparing the control-overhead to the actual data-bearing > traffic, rather than focusing solely on the difference in control traffic > between end-host and intermediary based solutions. > > Having a tunnel-router do the liveliness tests for 1000 hosts might save > 999 instances of control traffic, but if the 999 instances of control > traffic comprise 1-2% of the data traffic - then should we care? (Is > there a data-communications version of Amdahl's Law I can quote here?). > > By my back-of-the-envelope calculations, a Shim6/REAP solution has > Order(1.2%) overhead relative to data-traffic (on a low amount of > traffic, 24kB - e.g. fetching the google front-page) for the normal > case. Failure cases presumably might take slightly more - but failure is > not the common case. Solid quantitative studies would be really useful.
Could you show us your BOTEC? I've been meaning to go gather some real numbers. Scott _______________________________________________ rrg mailing list [email protected] http://www.irtf.org/mailman/listinfo/rrg
