IDS mailing list archives
Re: Auto-sensing for IPS devices
From: Joel M Snyder <Joel.Snyder () Opus1 COM>
Date: Mon, 19 Sep 2005 12:48:45 -0700
Setting a switch port to 100-TX will force any decent NIC on a host to link up at that setting. I would trash any NIC that doesn't. It's not necessary to force the link mode of the NIC if the switch doesn't auto-negotiate - the host NIC will find the desired link setting.
No, that's not the way it works. What you're doing is forcing the NIC to go into fallback mode, and what you're hoping is that it will be 100Mbit/Full Duplex. It happens that most NICs do that, and this is why the results you're seeing are as favorable as they are. If you picked a different speed or duplex, you'd have a bunch of NICs that would suddenly stop working.
However, with the world of 1000Mbit pushing 10/100 out of the way, your technique is going to result in much lower success rate and much higher customer support calls and problems.
If you want reliable operation, you must set speed and duplex settings on both ends. There is no concept of a NIC "figuring it out" or being able to be "forced." If you turn off autonegotiate, there is no way in the standard for the NIC to sense what the speed & duplex settings are.
jms -- Joel M Snyder, 1404 East Lind Road, Tucson, AZ, 85719 Phone: +1 520 324 0494 (voice) +1 520 324 0495 (FAX) jms () Opus1 COM http://www.opus1.com/jms Opus One ------------------------------------------------------------------------ Test Your IDS Is your IDS deployed correctly?Find out quickly and easily by testing it with real-world attacks from CORE IMPACT. Go to http://www.securityfocus.com/sponsor/CoreSecurity_focus-ids_040708 to learn more.
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Current thread:
- Auto-sensing for IPS devices ferg (Sep 14)
- Re: Auto-sensing for IPS devices Lachlan Bowes (Sep 14)
- Re: Auto-sensing for IPS devices Joel M Snyder (Sep 15)
- Re: Auto-sensing for IPS devices Lachlan Bowes (Sep 15)
- Re: Auto-sensing for IPS devices Joel M Snyder (Sep 15)
- Re: Auto-sensing for IPS devices Tim Holman (Sep 15)
- Re: Auto-sensing for IPS devices Packet Man (Sep 19)
- Re: Auto-sensing for IPS devices Joel M Snyder (Sep 19)
- <Possible follow-ups>
- Re: Auto-sensing for IPS devices gmail (Sep 14)
- RE: Auto-sensing for IPS devices McKinley, Jackson (Sep 16)
- Re: Auto-sensing for IPS devices Sap . (Sep 16)
- Re: Auto-sensing for IPS devices djmeier (Sep 22)
- Re: Auto-sensing for IPS devices Lachlan Bowes (Sep 14)