A 2007 study found that more than a quarter of Web servers have their clocks off by more than 10 seconds. This is true of desktop systems, servers, mobile devices and embedded systems like HVAC, alarm systems and electronic doorknobs. This can be a problem if you are trying to figure out an attack that originated inside your organization. Having the correct time is important for security because system clocks are used for a lot more than just displaying the current time on your organization’s homepage. If the time-of-day clock is wrong, log files are also wrong.”]

