impossible circuit

Andy Johnson andyjohnson at
Wed Aug 13 09:42:15 CDT 2008

> The only things I can think of that might be the cause are 
> misconfiguration in a DACS/mux somewhere along the circuit path or perhaps 
> a mishandled lawful intercept.  I don't have enough experience with either 
> or enough access to the systems that provide the circuit to do any more 
> than speculate.  Has anyone else ever seen anything like this?

I'm not sure how a DACS/mux misconfiguration would do this. There would have 
to be some intelligent device grabbing those IP packets and forwarding them 
on to another IP router, which seems really likely.

Have you noticed any unusual shifts in pattern on the internal network of 
your Ocala office? I wonder if somebody decided it would be clever to start 
up a VPN tunnel on a host inside your network, and also set the host in 
promiscuous mode, forwarding every packet it gets back out that tunnel.

The only argument I can come up against this tunnel/host, is that when you 
changed line encapsulation modes, it went away. However, could have just 
dropped the tunnel or the host that was misbehaving decided it was a good 
time to stop.

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