[wplug] Tapping into an Ethernet connection

[Rob Jeffries]

Regarding the hand-made tap, did you try switching the hosts around?
Because a tap will only allow receipt of packets, i wonder if the
problem might be a matter of positioning.

Also, if hand made is the route you're comfortable with, you might find
this interesting:
http://www.instructables.com/id/Make_a_Passive_Network_Tap/

Also don't forget about EMI, depending on what type of work, equipment
sensitivity, removing the cat 5/6 shielding might be its own source of
quirks.

** usual disclaimers and whatnot **

-rj

On Mon, 2009-05-18 at 14:03 -0400, Weber, Lawrence A wrote:
> Thanks for all of the good ideas.  Over the weekend I was able to
> purchase a couple of very old Netgear hubs that are really hubs.  They
> offer the advantage of having a switchable uplink port so I can use it
> to tap into both directly connected and network connected devices.
> The price was acceptable, around $20.00 each.  They are only 10Meg.  I
> will just have to live with that.
>  
> I also tried several of the modified wire ideas that were offered.  I
> had an old network connector that had an RJ-45 socket on two ends and
> a plug out of the middle.  A little rewiring and I can at least tap
> traffic in one direction.
>  
> As soon as I find my old PCMCIA - Ethernet card, I am going to try
> creating a bridge in my PC and tapping in that way.  This could be the
> most convenient way if I can get to work.
>  
> Not sure about the Barracudatap.  Looks like it needs two Ethernet
> ports on my test PC.
> 
> 
> ______________________________________________________________________
> From: wplug-bounces+lawrence.weber=ansaldo-sts.us at wplug.org
> [mailto:wplug-bounces+lawrence.weber=ansaldo-sts.us at wplug.org] On
> Behalf Of Weber, Lawrence A
> Sent: Friday, May 15, 2009 10:04 AM
> To: General user list
> Subject: [wplug] Tapping into an Ethernet connection
> 
> 
> 
> I have been trying to tap into an Ethernet connection between two
> pieces of equipment that we have designed.  I have found a cheap hub
> at only one Best Buy that allows me to use WireShark to view
> the messages.  However they are only 10Meg Hubs and eventually I am
> going to need to run at 100Meg.
>  
> I have two other Linksys hubs (NH1005 and EFAH08W) that are listed as
> "Network Hub" and "Workgroup Hub".  Both of these older (5 yr?)
> devices seem to be switches and not hubs.  I looked on line and can
> only find used 4 port hubs, but I am concerned that they are also just
> switches.  Is there any way to know if a hub is a hub and not a
> switch?  Or, is there another way to use WireShark to view traffic?
>  
> Lawrence. A. Weber 
> Consulting Engineer
> 
> image001
> 
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