Re: How accurate is ping?

From: Jerry Smiley (jsmiley_at_nc.rr.com)
Date: 04/07/04 

Date: Wed, 07 Apr 2004 11:49:02 GMT

Marc Fouquet wrote:

> When I ping machines in my 100 MBit Network it appears to me like ping can
> measure times very accurately (+- 100 microseconds or better).
>
> However when ones reads about timing measurements in Linux it always
> sounds like +-10 ms are the best accuracy one can expect from any program
> because of "ticks", taskswitching etc.
>
> How reliable are the mesurements performed by ping? Does it use special
> techniques to be more precise than other "user mode" programs (I read that
> root rights are needed to send ICMP packets)?
>
> Thanks
> Marc

man ping

May answer some of your questions...also giving an user root priv will
allow you to run 'icmp' packets too...

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