Hi David, Please forward me a copy of your research report.
Thanks, Bruce Johnson | Network Engineering Partners Healthcare | 617.726.9662 bjohns...@partners.org<mailto:bjohns...@partners.org> On May 10, 2012, at 3:11 PM, "David J Molta" <djmo...@syr.edu<mailto:djmo...@syr.edu>> wrote: I had some students do a project this semester where they compared aggregate throughput on a standard 3-channel model and two alternative 4-channel models. This was Cisco 2-stream 11n, a single client running iXChariot downstream throughput test. 3-Channel (1,6,11) 185 Mbps 4-Channel (1,4,7,11) 153 Mbps 4-channel (1,4,8,11) 98 Mbps They also ran a 3-channel test, 4 AP's with two AP's on Channel 1, the other two on 6 and 11. The goal here was to assess the incremental improvement in capacity when two AP's are contending for use of a common channel. Aggregate throughput in that scenario was 160 Mbps but the thing that was most interesting about that test was that the two AP's did not share the channel evenly. One AP on Channel 1 got 58 Mbps of throughput while the other got 12 Mbps. These tests appear to support the hypothesis that adding more AP's in a dense configuration in the 2.4 Ghz band does not result in significant added capacity when AP's are experiencing co-channel interference. It is important to note that our tests focused on downstream throughput, which would probably be the worst-case scenario for co-channel interference. I had another team perform some testing of Ruckus' ChannelFly technology, which often uses non-standard channels. In that testing, we have noted modest improvements in performance compared to the classic 3-channel model. I'd be happy to share the report with people who are interested. Dave Molta From: Lee Badman <lhbad...@syr.edu<mailto:lhbad...@syr.edu>> Reply-To: The EDUCAUSE Wireless Issues Constituent Group Listserv <WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU<mailto:WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU>> Date: Tue, 8 May 2012 14:34:19 +0000 To: <WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU<mailto:WIRELESS-LAN@LISTSERV.EDUCAUSE.EDU>> Subject: [WIRELESS-LAN] 4-channels in 2.4 GHz With no intent to open a conversational can 'o worms, I'm curious if anyone is running a 4-channel plan on their production WLANs, that is willing to share their opinions and experiences on the topic. Thanks- Lee Lee H. Badman Wireless/Network Engineer, ITS Adjunct Instructor, iSchool Syracuse University 315.443.3003 ********** 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/. The information in this e-mail is intended only for the person to whom it is addressed. If you believe this e-mail was sent to you in error and the e-mail contains patient information, please contact the Partners Compliance HelpLine at http://www.partners.org/complianceline . If the e-mail was sent to you in error but does not contain patient information, please contact the sender and properly dispose of the e-mail. ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
