Monitoring office web use

[Sedat DOĞRU <sdogru () blue-tec net>]

Hi,

We are searching some (preferrably free source or at most cheap) tools 
that can be used to monitor internet usage. The tool should be able to 
runon linux, directly on the command line or as a deamon.The tool should 
provide us the DNS names of the hosts that are connected to together 
with the connection times.

I have done a search on google but could not find only some advanced 
(and probably expensive) tools.

I've found that with extra scripting effort tcpdump, snort or tcpflow 
can be made do the work, but I want to first find an easier solution

If you know any tools, please let me know

Thanks in advance,


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Sedat Dogru