North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: Network for Sale
> >no, that is not the problem. oh i admit that ping time jitter is ~random. > >but even if it weren't, RTT doesn't drive performance, (bw*delay)-loss does. > > And how does "delay" differ from RTT, except for the obvious constant > factor? my point wasn't that rtt didn't matter but that bandwidth and loss also matter. so does filesize. for a 2MB GIF i'd rather have a 900ms * 622Mb/s (satellite?) link. for a 2K frame i'd rather have a 60ms * 56K link. using RTT by itself as a performance predictor is just silly. same for aspath length. the only way to know if performance will differ between server/proxy A vs B when talking to client C is to serve from both and see what the tcp window does and what the total bytes/sec are (if the file is long enough for those to matter.) the data then decays rapidly since congestion and routing will change after measurement.
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