Sites running on BSD operating systems occupied the first four places: Secure Dog Hosting runs OpenBSD, Pair Networks, INetU, and IPowerweb all use FreeBSD. The top placed European company site was Energis, who provide the connectivity for Netcraft's own web sites. None of the performance measurement points is on Energis' network.
Netcraft measure and makes available the response times of fifty three leading hosting providers' sites The performance measurements are made at fifteen minute intervals from four separate points around the internet, and averages are calculated over the immediately preceding 24 hour period.
Fuller information on the measurement process and current measurements are available.