Even with this design, my understanding is that Cisco recommends 100Mhz between channels on an AP. I assume that’s center frequency separation with 40Mhz channels (20Mhz channels shouldn’t need that much and 80Mhz channels would require considerably more), but I didn’t ask.
Chuck From: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:[email protected]] On Behalf Of Jeffrey D. Sessler Sent: Thursday, June 30, 2016 11:50 AM To: [email protected] Subject: Re: [WIRELESS-LAN] Turning off 2.4 on a select SSID? In the Cisco 3800 dual-radio design, while the fixed 5Ghz radio is omni in azimuth, the XOR radio when running in 5Ghz is directional – this is one of the mitigation techniques mentioned in the 7signal video. The directional (micro cell) is supporting the high-bandwidth multi-spatial 11ac clients under it, and the one spatial 11ac, legacy, etc. clients can be pushed to the omni (macro cell). At the end of the day, I think the XOR (flex) radio is fantastic investment protection. Instead of having to deal with (and waste a lot of time on) 2.4 overpopulation and unused radios, you gain a huge amount of flexibility. I’ve got a new residence hall coming online in a few weeks that will be equipped with about 100 of the new Cisco 3800-series (and multi-gig) so I’ll no doubt have a bit of real-world data to share. Jeff From: "[email protected]" <[email protected]> on behalf of Kees Pronk <[email protected]> Reply-To: "[email protected]" <[email protected]> Date: Thursday, June 30, 2016 at 5:23 AM To: "[email protected]" <[email protected]> Subject: Re: [WIRELESS-LAN] Turning off 2.4 on a select SSID? All, Little kick at the discussion from a while ago: There is a YouTube video now from 7signal in which dual 5GHz radio setup is discussed: <https://youtu.be/6eueR3PYXlA> https://youtu.be/6eueR3PYXlA (from 11:30 in the video). Pretty interesting! BR, Kees Van: Kees Pronk Verzonden: donderdag 7 april 2016 13:45 Aan: [email protected] Onderwerp: RE: [WIRELESS-LAN] Turning off 2.4 on a select SSID? Hi Chris, “you could in theory double the airtime available” I would be interested in your actual experience with this. Now that a few vendors have taken this approach and others stay away from this. Arguments in favor of 5/5 you will find these abundant on the vendors marketing pages, but how about : Extra COGS (band pass filters etc), extra complexity with your channels plans (need a lot of separation between the 5/5 radios), you must enable DFS channels on every AP but what about false positive radar detects? What about the 2 radio’s ‘deafening’ each other while trying so send/receive at the same time. Please keep us posted and maybe others testing with this 1. Innovation 2. Marketing gimmick (pick one ;-) Best regards, Kees Van: The EDUCAUSE Wireless Issues Constituent Group Listserv [ <mailto:[email protected]> mailto:[email protected]] Namens Larry Dougher Verzonden: donderdag 7 april 2016 03:11 Aan: <mailto:[email protected]> [email protected] Onderwerp: Re: [WIRELESS-LAN] Turning off 2.4 on a select SSID? Thanks Chris! Larry Dougher Chief Information Officer <http://its.wsesu.net> Information Technology Services <http://wsesu.net> Windsor Southeast Supervisory Union 127 State Street, Windsor, VT 05089 <mailto:[email protected]> Email | <http://goo.gl/gEAdt> Google+ | <http://twitter.com/larrydougher> Twitter | <http://www.linkedin.com/in/larrydougher> LinkedIn | 802.674.8336 On Wed, Apr 6, 2016 at 2:45 PM, Chris Adams (IT) < <mailto:[email protected]> [email protected]> wrote: Larry, We have deployed 802.11ac WAPs in many locations, but only have 80mhz channels enabled sparingly around campus. My hope is that by having the SDR option, we could configure 2x 5ghz radios with either 20Mhz or 40Mhz channels, logically operating as 2 WAPs. Our wireless use case is primarily for internet access – we just don’t have a need for true wave1/2 802.11ac throughputs at this time. To see true Wave2 throughputs, I believe the client WNIC would need to be upgraded. If we could operate 2 “logical” 5ghz WAPs from a single unit for a small increase in price, I think this is where our greatest benefit would be at this time as you could in theory double the airtime available. This is based on several assumptions I am making – I have not gotten my hands on the new AP250 yet but I am actively looking to do so. <http://boundless.aerohive.com/blog/Designing-WLANS-What-If-we-could-double-our-airtime-at-5-GHz.html>http://boundless.aerohive.com/blog/Designing-WLANS-What-If-we-could-double-our-airtime-at-5-GHz.htmlThanks,Chris AdamsDirector, Network & Telecom ServicesDivision of Information TechnologyUniversity of North GeorgiaFrom: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:<mailto:[email protected]>[email protected]] On Behalf Of Larry DougherSent: Wednesday, April 6, 2016 2:28 PMTo: [email protected]<mailto:[email protected]>Subject: Re: [WIRELESS-LAN] Turning off 2.4 on a select SSID?Chris,I have a question about the AP250, but may be a question about MU-MIMO moregenerally. So, all things being equal, would a 5Ghz 802.11ac device/clientsee any benefit from a Wave 2 AP or would that device/client have to have anupgraded/new 802.11ac 5Ghz Wave 2 chip to see a benefit?Thanks,Larry DougherChief Information Officer <http://its.wsesu.net> Information Technology Services <http://wsesu.net> Windsor Southeast Supervisory Union127 State Street, Windsor, VT 05089 <mailto:[email protected]> Email | <http://goo.gl/gEAdt> Google+ |<http://twitter.com/larrydougher> Twitter |<http://www.linkedin.com/in/larrydougher> LinkedIn | <tel:802.674.8336>802.674.8336On Wed, Apr 6, 2016 at 1:30 PM, Chris Adams (IT) <[email protected]<mailto:[email protected]> > wrote:I echo Jeremy’s sentiment – our experience with band-steering has beenoverwhelmingly positive. We are also not (currently) using DFS channels –but may be revisiting this soon. I’d estimate almost 2/3 of our 2.4ghzradios are disabled.I am very happy to see the new Aerohive AP250 has a SDR with the option ofdisabling the 2.4ghz radio in favor of having 2x 5ghz radios.Thanks,Chris AdamsDirector, Network & Telecom ServicesDivision of Information TechnologyUniversity of North GeorgiaFrom: The EDUCAUSE Wireless Issues Constituent Group Listserv [mailto:<mailto:[email protected]>[email protected]] On Behalf Of Jeremy GibbsSent: Wednesday, April 6, 2016 1:27 PMTo: <mailto:[email protected]>[email protected]: Re: [WIRELESS-LAN] Turning off 2.4 on a select SSID?I find the opposite to be true with band steering. If we turn it off, themajority of our clients won't connect to 5 Ghz, even if they are right abovean AP. This causes lots of disconnect problems and congestion in the 2.4Ghz spectrum. Turning band steering on fixes the problem for us.--Jeremy L. GibbsSr. Network EngineerUtica College IITSOn Wed, Apr 6, 2016 at 1:18 PM, Turner, Ryan H <[email protected]<mailto:[email protected]> > wrote:All,This is probably a fool’s errand, but we are debating experimenting withturning off the 2.4 spectrum on our eduroam SSID on parts of campus thathave a dense 5 gig coverage. We’ve always positioned eduroam as the premiumSSID, and left a WPA2-PSK SSID for all the rest that don’t support advancedEAP methods. We are debating trying this in just the IT building to start(see how many people scream). Has anyone done anything like this? Thegoals would be to continually remove traffic from the garbage bands,hopefully increasing client performance. Band steering isn’t very good.Thanks,Ryan TurnerThe University of North Carolina at Chapel [email protected] <mailto:[email protected]>********** Participation and subscription information for this EDUCAUSEConstituent Group discussion list can be found athttp://www.educause.edu/groups/.********** Participation and subscription information for this EDUCAUSEConstituent Group discussion list can be found athttp://www.educause.edu/groups/.********** Participation and subscription information for this EDUCAUSEConstituent Group discussion list can be found athttp://www.educause.edu/groups/.********** Participation and subscription information for this EDUCAUSEConstituent Group discussion list can be found athttp://www.educause.edu/groups/.********** Participation and subscription information for this EDUCAUSEConstituent Group discussion list can be found at<http://www.educause.edu/groups/> http://www.educause.edu/groups/.********** Participation and subscription information for this EDUCAUSEConstituent Group discussion list can be found at<http://www.educause.edu/groups/> http://www.educause.edu/groups/.Disclaimer ( http://www.avans.nl/over-avans/e-mail-disclaimer ) **********Participation and subscription information for this EDUCAUSE ConstituentGroup discussion list can be found at http://www.educause.edu/groups/.********** Participation and subscription information for this EDUCAUSEConstituent Group discussion list can be found athttp://www.educause.edu/groups/. ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
