Re: IPv6 and CDN's

[Owen DeLong via NANOG <nanog () nanog org>]

Well, 1.4x faster is a bit of an odd metric. I presume that means that connection set up times measured were on average
1/1.4 times as long for IPv6 as they were for IPv4, but there are other possible interpretations.

So really, that’s a convoluted way of saying it takes 29% less time to set up an IPv6 connection than an IPv4 
connection on average.

I can believe that is likely in a scenario where one is dealing with IPv4 NAT overhead.

It’s still probably rounding error for any real world purpose, since we’re probably talking about something that 
normally takes
between 50 and 150 ms, so if it takes 1.4 times as long in IPv4, that’d be 70-210 ms, so still mostly under 1/5th of a 
second,
which is not below human perception, but likely below human notice.

Owen


> On Nov 27, 2021, at 14:30 , Michael Thomas <mike () mtcc com> wrote:
>
>
> On 11/27/21 2:22 PM, Owen DeLong via NANOG wrote:
> > Actually, I think it’s in the fine print here…
> >
> > “Connection setup is 1.4 times faster”. I can believe that NAT adds almost 40% overhead to the connection setup 
> > (3-way handshake) and some
> > of the differences in packet handling in the fast path between v4 and v6 could contribute the small remaining 
> > difference.
> >
> > I doubt it is due to different connections, since we’re talking about measurements against dual-stack sites reached 
> > from dual-stack end-users,
> > very likely traversing similar paths.
> 40% in isolation is pretty meaningless. If it's 40% of .1% overall it's called a rounding error.
>
> Mike