Wrong math. The internet average packet size is very close to 750B - it has been published many times in many places.
Wrong assumption about the user needs. User does not care about serialization time. He/she cares about FCT==Flow Completion Time. If one would get 2.6% less on the bottleneck, then his FCT would be 2.6% longer. His page would open later. His file would download later. Ed/ > -----Original Message----- > From: William Herrin <[email protected]> > Sent: Tuesday, December 2, 2025 23:37 > To: North American Network Operators Group <[email protected]> > Cc: Marco Moock <[email protected]>; Vasilenko Eduard > <[email protected]> > Subject: Re: IPv6 Performance (was Re: IPv4 Pricing) > > On Mon, Dec 1, 2025 at 11:09 PM Vasilenko Eduard via NANOG > <[email protected]> wrote: > > Fundamentally, IPv6 should be slower because of the bigger > headers/overhead. > > Hi Vasilenko, > > Everything else being equal, IPv6 would have roughly 1.3% less throughput. > The math is straightforward: 20 bytes larger header on > 1500 byte packets, 20/1500 = 0.013 for throughput. > > The latency difference is determined by the total packet size including header > and data which is the same or smaller with IPv6 -- both are limited by the > 1500 > byte Ethernet frame size. Even on the initial packets smaller than the frame > size, the difference in transmission time over gigabit or better links is so > small > it disappears into the noise. So, no impact at all. > > That's it. > > If you're experiencing slower IPv6 or slower IPv4, it's all about the network > engineering. Your network path to a server which satisfies one address is > longer or transits a slower link in the path than the one which satisfies the > other. > > Regards, > Bill Herrin > > > -- > For hire. https://bill.herrin.us/resume/ _______________________________________________ NANOG mailing list https://lists.nanog.org/archives/list/[email protected]/message/TAMQ2C47CSSC7MFSQJDL22VMRZMLOQHZ/
