MRTG wrong speed monitored

[Collen Blijenberg <MLHJ>]

well, i got the following prob..

i use mrtg to monitor the spped of network and internet..
i was downloading from internet (few iso's)
and mij download speed was (aprox) 300kb a sec..
in my mrtg graph, it showed up as 120 kbyte and 95kbit.. (aprox)
nothing even close to the 300kb..  my snmp.conf is very simple:
--------------------------------
[snmp.conf]
rocommunity     community
rocommunity     community
---------------------------------
[mrtg.cfg]
target[ww]: 2:community at 192168.2.1:
..
..
options[ww]: growright noinfo bits
---------------------
quite basic as you can see ..
anny clue's why inet traffic speed is in correct ??

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Collen Blijenberg (Systeem/Netwerk Beheerder)

Montessori Lyceum 
Herman Jordan
Zeist