Operating systems used by the ten most reliable sites was quite mixed, with four running Linux, four FreeBSD and two Windows (Datapipe on Windows 2003 and EasyNet on Windows 2000).
Netcraft measures and makes available the response times of fifty 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.
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