hello
there are two tools that come to mind first is ntop you will find it in EPEL
its a great tool that will tell you what the network traffic is doing
and has a nice web GUI.

another great tool is smoke ping http://oss.oetiker.ch/smokeping/
there is no RPM for it that I know of but it is an easy way to test
your connectivity and graph your latency and it even does email
alerting.

On Wed, Mar 27, 2013 at 3:36 PM, Todd And Margo Chester
<[log in to unmask]> wrote:
> Hi All,
>
> I have a Cent OS 5.x server sitting on a DSL line
> acting as a firewall.  I have noticed that there are
> dead spots, up to a minute, every so often in their
> Internet service.
>
> It could be a storm on someone's part, but the worst
> they run is IMAP.  No music; no video.
>
> Is there a utility I can run to map this?
>
> Many thanks,
> -T