We don't enable 802.1x on server switchports. That stuff is in the datacenter or another secured area where people can't exactly unplug it and plug in without us knowing :-)
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Dahl, Kevin Sent: Thursday, August 05, 2010 1:26 PM To: PaulDotCom Security Weekly Mailing List Subject: Re: [Pauldotcom] Locking down Ports and DHCP How do those of you who are using 802.1x solve the problem with patching and/or nightly backups ?? K-Dee -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Jody & Jennifer McCluggage Sent: Thursday, July 29, 2010 8:00 PM To: 'PaulDotCom Security Weekly Mailing List' Subject: Re: [Pauldotcom] Locking down Ports and DHCP I agree with Tim about recommending 802.1x. You can set it up so that the switches will not allow access until the end-user authenticates themselves on the network (via Windows RADIUS service, IAS, communicating with a domain controller). The 8021.X clients on Windows XP SP3 and higher are pretty stable (it will work on lower versions but SP3 added some 802.1x improvements). As Tim pointed out, more and more embedded devices such as printers are now also supporting 802.1x. For other embedded devices (older printers, copiers, UPS, etc), you can utilize MAC address filtering. This is less of an issue with these since they tend to be fairly static (i.e. they won't be moving around much) and usually have some additional compensating physical controls. You will probably want to use MAC Address filtering with your servers too. 802.1x tends not to work well with servers since it requires authentication prior to granting port access. If someone has physical access to the ports that your servers are using, port authentication is the least of your problems! Also as Tim said, keep in mind that you are adding some additional moving parts so more things can go wrong (8021.x client issues, switch issues, or RADIUS server issues - over the years I have had to deal with all three at one time or another but nothing real major). That being said, except for the occasional minor headache, I have had very little issues with it over the years. Also keep in mind that the workstation will not have access to the network until the user authenticates with an approved domain level account. Let me know If you want some examples on how to set up using Cisco switches and Windows workstations and radius/domain server. Jody -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Bugbear Sent: Thursday, July 29, 2010 9:04 AM To: PaulDotCom Security Weekly Mailing List Subject: Re: [Pauldotcom] Locking down Ports and DHCP First and foremost get your company policies and procedures in place if you have not yet. Also, you will need "buy in" from the support staff because their helpdesk calls are going to increase. With that said, I would look at 802.1x Assuming you are a Windows shop and your switches support it (most modern switches do), take a look. I have leveraged it somewhat successfully. I personally do not do any NAP/NAC (remediation), I just very simply use Radius to auth the domain computers and domain users. If joined to the domain and a member of this group then they are on the production LAN, if not the switches will dynamically VLAN them to a Quarantine VLAN. What you do with "guests" is up to you from there. You can wait for the helpdesk call or you could provide restricted internet access. If the later, consider the appropriate egress filtering, logging, alerting, IDS, etc... Also consider using PAT to give that network a unique public IP. Lastly, consult your legal team to draw up some language for "guests" to click through via Web Auth/Captive Portal (most modern switches support this too). The language should note that your Company is not responsible / liable and you hold the right to monitor unencrypted traffic on the network (careful with what type of monitoring - headers verse full content) Most Printers, Scanner, AP's etc.. support 802.1x these days. An alternative (not a very good one) would be port security via the mac addr (but that will only keep the layman off). Now the part your probably going to struggle with. The supplicant. There are many. MS Windows XP SP3 and above has one built in and supports GPO control. There are also products like Juniper/Odyssey and Cisco Clean Access (Which i think just got EOL). They all suck (excuse me have their limitations). The Windows supplicant in Windows 7 seems to have been approved quite a bit however. In XP there were issues with legit end users being temp flipped to quarantine (while radius auth's them < the default behavior). Once flipping back and the DHCP client will sometimes not get an updated IP for that subnet. To date I have not found a workaround, except Windows 7. Also, if your admins are using logon scripts and not doing so through GPO they will need to as they will not run post Auth Other tech out there includes tracking/alerting after the fact (someone being on your network). Hope this helps Tim On Wed, Jul 28, 2010 at 5:36 PM, Tyler Robinson <[email protected]> wrote: > I am coming into an environment of over 1000 clients everything is > setup DHCP except printers and servers I am trying to work towards a > much more secure network but am at a loss of how to start locking down > switches and DHCP I want to make sure no one is plugging in > unauthorized devices or rogue devices for that matter so just > wondering how everyone else is securing there networks as always > pauldotcom listeners are the best and all help is welcomed. > > TR > > _______________________________________________ > Pauldotcom mailing list > [email protected] > http://mail.pauldotcom.com/cgi-bin/mailman/listinfo/pauldotcom > Main Web Site: http://pauldotcom.com > _______________________________________________ Pauldotcom mailing list [email protected] http://mail.pauldotcom.com/cgi-bin/mailman/listinfo/pauldotcom Main Web Site: http://pauldotcom.com _______________________________________________ Pauldotcom mailing list [email protected] http://mail.pauldotcom.com/cgi-bin/mailman/listinfo/pauldotcom Main Web Site: http://pauldotcom.com _______________________________________________ Pauldotcom mailing list [email protected] http://mail.pauldotcom.com/cgi-bin/mailman/listinfo/pauldotcom Main Web Site: http://pauldotcom.com ****************************************************************************** This email contains confidential and proprietary information and is not to be used or disclosed to anyone other than the named recipient of this email, and is to be used only for the intended purpose of this communication. ****************************************************************************** _______________________________________________ Pauldotcom mailing list [email protected] http://mail.pauldotcom.com/cgi-bin/mailman/listinfo/pauldotcom Main Web Site: http://pauldotcom.com
