Re: how to make the sniffer quicker?

[David Young <dyoung () pobox com>]

On Wed, Jan 17, 2007 at 10:39:55AM -0000, David Lopez wrote:
> Hi
>
>  
>
> I'm developing a position system for my PhD.
>
> This system is based on Round Trip Time measurements.
>
> I'm getting the timestamp of the packets using Tethereal and the Mactime
> in the Prism Monitor Header
>
> My problem is: the sniffer is too slow.

How fast is your computer?  Do you use a Prism radio?  A host has to read
packets from the Prism II/2.5 radios using programmed I/O, which is slow.

> When I'm flooding the receiver with pings, using the linux command ping
> -f, if I send X in one second I cannot get this number of packets in the
> sniffer, I always get less, around the 10%. 

At what rate does the sniffer receive packets?  Could it be that ping
-f produces packets faster than the radio can transmit them?  That is,
the packets may be dropped on the sender side.

Dave

-- 
David Young             OJC Technologies
dyoung () ojctech com      Urbana, IL * (217) 278-3933
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