Sucuri has published the results of performance tests it conducted to compare the response time of websites over IPv4 and IPv6.
It ran 1,000 tests at six locations – four in the US, two in the UK – with each location tested with 22 domains. 264,000 tests were conducted in total.
“We selected the top sites that support both IPv4 and IPv6 from multiple locations to identify which one performs better,” said Sucuri.
“We used the curl utility to collect data for connect time and total time, as these metrics represent what users notice as part of their browsing experience.”
To account for different sources of variability, it used a mixed-effects model.
IPv4 is faster
Sucuri said the tests proved IPv4 is slightly faster than IPv6.
However, the location can affect the speed of IPv4 and IPv6.
The differences are small, fractions of a second, which does not mean much for human browsing.
“One interesting conclusion is that IPv6 seems to be slightly less stable compared to IPv4. It generates more outliers,” said Sucuri.
“Perhaps the way IPv6 deals with additional headers in contrast to IPv4 may be influencing this difference.”
This stability is observed most evidently on sucuri.net and cloudflare.com, which are both services that deal with web security.
Graphs for each location are available on Sucuri’s site.