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Re: I found the missing 30 milliseconds!
On Tue, 16 Sep 1997, Kent W. England wrote: That's all well and everything, but I'll put $5 down that says everyone here used standard 56-byte ICMP payload for their pings, which makes the packet less than 100 bytes total. /cah ==>Everyone; ==> ==>You can't send a packet out an interface until the entire packet has been ==>received on the incoming interface. Now if we assume 1500 byte packets (the ==>new de facto MTU on all modern Internet backbones) and DS-3 pipes, then it ==>takes about 250 microseconds to buffer the pkt on each hop. Since the US ==>internet backbone from coast to coast is about 120 hops, there's your 30 ==>milliseconds and Bob's your uncle. ==> ==>Did I do the arithmetic right? ==> ==>--Kent, ever helpful with NANOG metrication ==>;-) ==> ==>Well, back when us old guys were young, switching delay *was* significant. ==>Did I ever show you my p4200? ==>