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Re: MTU of the Internet?
At 09:11 AM 2/5/98 -0500, Eric Osborne wrote: > >I think that "triple" is perhaps an oversimplification. This assumes that >without a 576-byte MTU, all packets would be 1500-byte MTUs. 1500/576 ~=~ 3. > >Remember, there's three kinds of average: mean, median, mode. While the mean >packet size may be 200-250 bytes, the mode and median are probably different. >I don't have any statistics on this, but I'd be willing to guess that if you >plotted the packet sizes frequency you'd see something like a bimodal curve, >with a small peak at around 64 (ping) and a larger one near 1500 (10Mbit >Ethernet/T1 MTU). As to median packet size, I have no idea. It's probably >somewhere in the middle. :) the real data sez... packet size distribution is roughly tri-modal the 25-jun-97 numbers show - roughly 38% at 40bytes (tcp acks mostly) - .6 41 - 6% 44 (syn+mss) - 1 52 - 10% 55 - .6 56 - .7 61 - 5% 576 - 12% 1500 nothing else accounts for >0.5% of the packets and for those that really care - 40 byte packets represent ~ 4% of the bytes-on-the-fiber - 552 16 - 576 8% - 1500 49% the median packet size is 56 bytes (http://www.nlanr.net/NA/Learn/packetsizes.html)