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Re: Hardware capture platforms

  • From: Larry J. Blunk
  • Date: Thu Jul 31 01:51:01 2008
Warren Kumari wrote:

On Jul 29, 2008, at 10:43 PM, Darryl Dunkin wrote:

Hubs sure are fun...


This might be a stupid question, but where can one get small hubs these days? All of the common commodity (eg: 4 port Netgear) "hubs" these days are actually switches.

What I am looking for is:
Small enough to live in my notebook bag (e.g.: 4 port with a wall wart.)
Cheap
Simple
10/100/1000Mbps

While a tap would work, I'd prefer a hub because I can then use it to connect machines together in a pinch. 

   D-Link sells a smallish 8-port managed Gigabit switch that allows
you to disable learning on the ports --  DGS-3200-10 --
http://www.dlink.com/products/?sec=0&pid=674
I don't know where they hide the manuals on the D-Link
US site, but Google turned them up on their Russian ftp server ??
While not incredibly cheap, it seems reasonable at about $300.
As a bonus, it seems to have pretty complete IPv6 support.

  We wanted to do something similar with a 10G switch (SMC8708L2).
It let's you set the size of the MAC table, but not to zero.   However,
we found that setting the size of the table to 1 entry effectively disabled
learning.



W
---

In the past I have bought some cheap 4 port commodity switches (form Circuit City or somewhere similar), found the datasheet for the chipset (it was a Broadcom something or other) and tied the pin to ground that disables the learning mode (actually, I think that the pin just set the size of the learning table to be 0 entries). While this works, doing it once was more than enough :-)

Nice hack!