Snort mailing list archives
RE: Is it really a HUB?
From: <bmcdowell () coxhealthplans com>
Date: Fri, 28 Nov 2003 15:05:46 -0600
I wonder if perhaps there's a business opportunity here, or perhaps simply an existing piece of hardware that would help deal with these problems. Imagine a tap/hub/whatever that one might plug into both the 10mbit and 100mbit 'sides' of such a device, and then deliver that combined 'signal' to a single ethernet port. Or, potentially, combining the span ports of two or more managed switches into a single 'signal feed'. One could show up onsite, plug in the 'feed device' into one or more ports on one or more devices and sniff away... Just a random thought, Bob -----Original Message----- From: snort-users-admin () lists sourceforge net [mailto:snort-users-admin () lists sourceforge net]On Behalf Of kenw () kmsi net Sent: Friday, November 28, 2003 2:17 PM To: Matt Kettler Cc: snort-users () lists sourceforge net Subject: Re: [Snort-users] Is it really a HUB? On Fri, 28 Nov 2003 14:06:01 -0500, you wrote:
At 11:31 PM 11/27/2003, kenw () kmsi net wrote:The problem is that the actual implementation may have more
switching
behavior than advertized.. all they've guaranteed is that the 10/100 segments are bridged.. but that doesn't mean that the 100mbit ports
can't
be fully switched with respect to each other too.According to Cisco's literature, these hubs provide "100-Mbps peak aggregate throughput". That implies no switching on the 100Mbps side.True, although they are free to give you more than advertised.
Implications
are not specifications. I've encountered at least one dual-speed hub, a netgear model, that
behaved
more like a switch than a hub between 100mbit ports. (I tried to hook a
100mbit/sec sniffer in between two 100mbit devices and saw nothing).
The
big difference is that it only supported half duplex, unlike most
switches. Interesting. I personally use a NetGear DS104 dual-speed hub, specially purchased for such work. I've never seen that behavior. I do, though, have to watch the port speed lights carefully, and hard-set the NIC interface speed at times. Vendor marketing types seem to see little harm in playing their usual games with terminology. They're usually right, unfortunately.
Basically all I was stating was that it *might* behave like a switch or
a
hub.. Despite the Cisco literature, I still see nothing in there that solidly ensures hub-like behaviors between 100mbit ports. Thus, I still
say
that either behavior is possible. It could act like a hub, or a switch, and neither behavior is
guaranteed by
the spec.
True. And it could even violate specs, for that matter (gee, that _never_ happens ;-/ ). The Principle of Least Amazement (aka Occam's Razor) would suggest that an auto-configuring sniffer NIC is the more likely culprit, and deserves close inspection. But I would pay dearly for the ability to generate a personal No Wierd Sh*t Zone. /kenw Ken Wallewein CDP,CNE,MCSE,CCA,CCNA K&M Systems Integration Phone (403)274-7848 Fax (403)275-4535 kenw () kmsi net www.kmsi.net ------------------------------------------------------- This SF.net email is sponsored by: SF.net Giveback Program. Does SourceForge.net help you be more productive? Does it help you create better code? SHARE THE LOVE, and help us help YOU! Click Here: http://sourceforge.net/donate/ _______________________________________________ Snort-users mailing list Snort-users () lists sourceforge net Go to this URL to change user options or unsubscribe: https://lists.sourceforge.net/lists/listinfo/snort-users Snort-users list archive: http://www.geocrawler.com/redir-sf.php3?list=ort-users ------------------------------------------------------- This SF.net email is sponsored by: SF.net Giveback Program. Does SourceForge.net help you be more productive? Does it help you create better code? SHARE THE LOVE, and help us help YOU! Click Here: http://sourceforge.net/donate/ _______________________________________________ Snort-users mailing list Snort-users () lists sourceforge net Go to this URL to change user options or unsubscribe: https://lists.sourceforge.net/lists/listinfo/snort-users Snort-users list archive: http://www.geocrawler.com/redir-sf.php3?list=snort-users
Current thread:
- Re: Is it really a HUB?, (continued)
- Re: Is it really a HUB? Kristofer T. Karas (Oct 29)
- Re: Is it really a HUB? Marc Quibell (Oct 28)
- RE: Is it really a HUB? Potts, Ross A. (Oct 29)
- Re: Is it really a HUB? Petriz, Pablo (Nov 26)
- Re: Is it really a HUB? Matt Kettler (Nov 26)
- Re: Is it really a HUB? kenw (Nov 27)
- Re: Is it really a HUB? Matt Kettler (Nov 28)
- Re: Is it really a HUB? kenw (Nov 28)
- Re: Is it really a HUB? Matt Kettler (Nov 28)
- Re: Is it really a HUB? kenw (Nov 28)
- Re: Is it really a HUB? Matt Kettler (Nov 26)