wireless printers in dorms

On Oct 30, 2012, at 13:53 , Tom O'Donnell wrote: > > I was wondering how other schools handle wireless printers in the > dorms. This seems to be the year everyone showed up with one, and > they're causing connectivity problems in our 2.4GHz space. How well do the printers work anyway wirelessly? Depending on the service advertisement protocols and printing protocols used, the client types, your authentication requirements (since most printers don't do WPA2-Enterprise/802.1X) and your subnetting/address assignment scheme, I wonder how successful people are at actually getting these things to work anyway. -- Julian Y. Koh Manager, Network Transport, Telecommunications and Network Services Northwestern University Information Technology (NUIT) 2001 Sheridan Road #G-166 Evanston, IL 60208 847-467-5780 NUIT Web Site: PGP Public Key: ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.

Message from dannyeaton@rice.edu

We as well do not allow them on the campus wireless, due to the 802.1x requirement. If a student registers the MAC with clean access, they can have it on the wired port and then print via IP over the wireless from anywhere on campus. We have an open-webauth "visitor" wireless, but printer can't accept the AUP, so that doesn't work for them either. They are not allowed on our network as they don't do 802.1x. We tell them in as many communications as possible that they should bring USB cables. We found that you can get 15 foot USB cables for a couple of bucks in quantity. We give them out during opening to those who didn't get the word and they appear to be very grateful. I couldn't imagine giving up a whole 2.4 channel. I would think that would be pretty devastating to our 2.4Ghz functionality. Pete Morrissey I was wondering how other schools handle wireless printers in the dorms. This seems to be the year everyone showed up with one, and they're causing connectivity problems in our 2.4GHz space. Are you able to keep them under control, or do you seek them out and make students to turn them off? They seem to push our AP's to other channels (usually to 1 and 11, since it looks like the printers often use ch 6) to prevent co-channel interference. But sometimes several adjacent AP's end up on the same channel, so either there's still co-channel interference or they're powered down so much that either way it can cause problems through a whole building. Our infrastructure is all Cisco: a WiSM running 7.0.230.0 managing a mix of AP1252's and AP1231's. The AP's have been better at assigning 2.4GHZ channels since we unchecked "Avoid Foreign AP interference" in DCA settings. Our DCA Channel Sensitivity is Medium, and our TPC settings are max. 30dMb, min. -10dBm, threshold -70dBm. We have Client Band Select on, but most of our clients stick with 2.4Ghz, even where 5GHz is available. We've seen noticeable improvement when we're able to locate an interfering printer, disable its wireless, and change channels, but it's a lot of work and not always successful. Lots of knocking on doors, some printers don't seem to let you disable wireless, and sometimes DCA doesn't seem to spread them back among all 3 channels, so we end up setting some channels manually. Are there other useful settings in the WiSM? Any other ideas? Thanks, ---------------------------------------------------------- Tom O'Donnell Senior Manager of Network and Server Systems Information Technology Services University of Maine at Farmington (207) 778-7336 ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/. !DSPAM:911,5090260374827917598546! ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.

Speaking only for me and not on behalf of my institution- I have heard enough first-hand narrative from students to have come to the belief that many printers that come to the dorms don't even get used, or get used until the ink cartridge runs out and then gets abandoned. Often, students have no clue about public printers until they are here for a bit (we tell them in the welcome packets, but you know how that can go). For the sake of WLAN performance, I'd like to make shared printers more plentiful and with generous quotas- along with going ever more paperless in classes. Wouldn't it be great to say "and you don't need a printer!" (And I'd like a pony.)    

We're seeing more and more on-campus offices (we have no residences) buying printers that are coming with 2.4GHz wifi, apparently turned on by default. (Recall that you only get 3 non-overlapping 2.4GHz channels in any area....) Twice we've seen such devices either broadcasting multiple (12-15) wireless MAC addresses/ESSIDs, or in one case changing MAC address about every 30 seconds. The language in our AUP prohibiting "use that interferes with the intended purpose" was crafted with things like DOS attacks in mind, but doesn't require any change to apply to interfering with campus WiFi service.... David Gillett CISSP CCNP

Has anyone declared 2.4Ghz hopeless and made a policy declaring that users that want a working well performing wireless network connection need to make arrangements to connect to the 5Ghz network? If a policy like that could fly, then it would be easier to run a 5Ghz network with great performance for all of the laptops to connect to. 2.4Ghz could become a best effort waste land polluted by all of the printers with their rogue ssid's, slowed down by the wii's that insist on making 802.11B connections before they'll make 802.11G connections, interfered with by the bluetooth, wifi-direct, etc. Of course, I guess this is only a good idea until 5Ghz becomes the new 2.4Ghz. I suppose it's probably only a matter of time until devices like printers have dual band radios and can cause 5Ghz problems too.

Banning 2.4 GHz would ban a large portion of the consumer PCs and mobile devices and all current game consoles. I know that would not work here. We initially only offered IPTV on 5GHz n and had to expand the offering to 2.4GHz due to complaints from students. Excluding game consoles would also be a very big issue here. Bruce Osborne Network Engineer IT Network Services   (434) 592-4229   LIBERTY UNIVERSITY Training Champions for Christ since 1971 -----Original Message----- From: Adam Forsyth [mailto:forsytad@LUTHER.EDU] Sent: Tuesday, October 30, 2012 8:41 PM Subject: Re: wireless printers in dorms Has anyone declared 2.4Ghz hopeless and made a policy declaring that users that want a working well performing wireless network connection need to make arrangements to connect to the 5Ghz network? If a policy like that could fly, then it would be easier to run a 5Ghz network with great performance for all of the laptops to connect to. 2.4Ghz could become a best effort waste land polluted by all of the printers with their rogue ssid's, slowed down by the wii's that insist on making 802.11B connections before they'll make 802.11G connections, interfered with by the bluetooth, wifi-direct, etc. Of course, I guess this is only a good idea until 5Ghz becomes the new 2.4Ghz. I suppose it's probably only a matter of time until devices like printers have dual band radios and can cause 5Ghz problems too.

To me, this whole mess has a lot of contributing factors in the aggregate. Lazy/dated/stuck-in-time client device makers, policy that is either lacking, not enforced, or impossible to practically enforce, merchants (like campus bookstores)not engaged or sympathetic to campus IT when it comes to getting the message out about what works and doesn't in the dorms, and users that are either hyper-clueless or hyper-savvy. Then there's the philosophical debates- "the dorm should be just like home, where people can do anything they want" versus "the dorms are more like a hotel- you play by the rules of temporary lodging" etc. And the fact that we tend to have zero control over client types, device health, and nuances like OS revisions and driver status per client. Sprinkle in each WLAN vendor's bugs and quirks for good measure, as standards-based WLAN is a bad joke these days from the antenna back. Put it all together, and one thing is certain- it's extremely difficult to promise any kind of per-user bandwidth on even the best WLAN when the RF environment is so variable, and there isn't enough staff in the world to run around trying to squelch every bit of interference that pops up where you have a large dorm environment. Happy sunny Wednesday, dagnammit. Love your show, Curmudgeonly in Syracuse. Lee H. Badman Network Architect/Wireless TME Information Technology and Services (ITS) Syracuse University 315 443-3003     -----Original Message----- From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU] On Behalf Of Osborne, Bruce W Sent: Wednesday, October 31, 2012 7:44 AM To: WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU Subject: Re: [WIRELESS-LAN] wireless printers in dorms Banning 2.4 GHz would ban a large portion of the consumer PCs and mobile devices and all current game consoles. I know that would not work here. We initially only offered IPTV on 5GHz n and had to expand the offering to 2.4GHz due to complaints from students. Excluding game consoles would also be a very big issue here. Bruce Osborne Network Engineer IT Network Services   (434) 592-4229   LIBERTY UNIVERSITY Training Champions for Christ since 1971 -----Original Message----- From: Adam Forsyth [mailto:forsytad@LUTHER.EDU] Sent: Tuesday, October 30, 2012 8:41 PM Subject: Re: wireless printers in dorms Has anyone declared 2.4Ghz hopeless and made a policy declaring that users that want a working well performing wireless network connection need to make arrangements to connect to the 5Ghz network? If a policy like that could fly, then it would be easier to run a 5Ghz network with great performance for all of the laptops to connect to. 2.4Ghz could become a best effort waste land polluted by all of the printers with their rogue ssid's, slowed down by the wii's that insist on making 802.11B connections before they'll make 802.11G connections, interfered with by the bluetooth, wifi-direct, etc. Of course, I guess this is only a good idea until 5Ghz becomes the new 2.4Ghz. I suppose it's probably only a matter of time until devices like printers have dual band radios and can cause 5Ghz problems too.

I wasn't intending to suggest a policy banning 2.4Ghz or saying that I wanted to stop offering service in that band.  Just thinking out loud of a policy that we'd make our best effort to make 2.4Ghz work, but 5Ghz would be the better performing more reliable network....I guess though, policy or not that's already how things are working out due to the nature of both bands and Rogue consumer devices.

I wasn't intending to suggest a policy banning 2.4Ghz or saying that I wanted to stop offering service in that band.  Just thinking out loud of a policy that we'd make our best effort to make 2.4Ghz work, but 5Ghz would be the better performing more reliable network....I guess though, policy or not that's already how things are working out due to the nature of both bands and Rogue consumer devices.

Also I suppose short of banning 2.4Ghz, it's hard to get student's attention to get them to buy 5Ghz capable computers, but I agree banning 2.4Ghz would cause many complaints.

Does anyone have methods that you've used that have been successful in educating students to make the choice to spend a few extra dollars for dual band wireless when they're purchasing a new laptop?