I think we are having two different conversations, and I have no idea what you are talking about right now.
What we were discussing has to do with channel sizes, epmp, and ubiquiti. In particular, why UBNT 40mhz isn't any better than 30mhz in terms of efficiency.
This part of the discussion has nothing at all to do with any theories on PPS you may have, other than those you have tried to inject into this discussion.
On Jun 8, 2015 10:07 AM, Rory Conaway <r...@triadwireless.net> wrote:
Excopt that as was mentioned before, the s/n ratio goes down and if you aren't hitting the limits of the physical layer in 20MHz, why do it?
Sent from fromm phone where I type with a single digit so please excuse shortcuts or typos.
Rory ConawayTriad Wireless
-------- Original message --------
From: Josh Reynolds <josh@spitwspots.com>
Date: 06/08/2015 12:43 PM (GMT-05:00)
To: af@afmug.com
Subject: Re: [AFMUG] EPMP 10 mhz vs 20mhz
I can assure you that on radios connected in a ptp config or small ptmp, that you will see more throughput on the 30mhz channel given a noise floor of -97 and signals in the mid -50s, even with nothing connected on the other side of the radios.
Its an efficiency issue.
On Jun 8, 2015 8:13 AM, Mathew Howard <mhoward841@gmail.com> wrote:
I kind of does, the way I understood it, that bottleneck limited you from really being able to do anything beyond what a 30mhz channel could support.Now that I think about it, I have seen 40mhz perform better than 30mhz... but yes, that was because of RF problems, and neither one was doing anything close to what it would with a good link.
On Mon, Jun 8, 2015 at 11:09 AM, Josh Reynolds <josh@spitwspots.com> wrote:
That is a bottleneck in the system, but not relevant as far as this discussion goes. That has nothing to do with the 30/40MHz channel efficiency per say.
On Jun 8, 2015 8:03 AM, Rory Conaway <rory@triadwireless.net> wrote:
The limitation on the older xm radios was pps. When you added a lot of small packets and airmax, you could drop down to as low as 40Mbps. In the real world in ptmp mode. We planned for 50mhz per AP with eveything g taken into account.
Sent from fromm phone where I type with a single digit so please excuse shortcuts or typos.
Rory ConawayTriad Wireless
-------- Original message --------
From: Josh Reynolds <josh@spitwspots.com>
Date: 06/08/2015 11:59 AM (GMT-05:00)
To: af@afmug.com
Subject: Re: [AFMUG] EPMP 10 mhz vs 20mhz
This. Thought it was pretty obvious but I guess I assumed too much out of some on this list ;)
On Jun 8, 2015 7:33 AM, Jeremy <jeremysmith2@gmail.com> wrote:
I think he is talking about using 40MHz channels on the older M series, that didn't have gig ports. It was my understanding that the processor would get taxed as well on a 40MHz channel, making 30MHz actually work better.
On Mon, Jun 8, 2015 at 9:24 AM, Josh Luthman <josh@imaginenetworksllc.com> wrote:
Ubnt and epmp have gig ports.
Josh Luthman
Office: 937-552-2340
Direct: 937-552-2343
1100 Wayne St
Suite 1337
Troy, OH 45373On Jun 8, 2015 11:20 AM, "Josh Reynolds" <josh@spitwspots.com> wrote:
I don't know how epmp does it.
For UBNT, a 30mhz channel is just a "fat" 20mhz channel in the atheros chip. Single operation. For a 40mhz channel, it's really two 20s, meaning radio operations are ran twice. Loss in efficiency, also marred by the lack of gigabit port.
On Jun 8, 2015 7:13 AM, Mathew Howard <mhoward841@gmail.com> wrote:
I've never seeing much difference in performance on the ubnt M series between 30mhz and 40mhz channels, so yes, I would say that is true... but I'm not sure how much applies to ePMP - they do have a much a faster processor and on a software level they are very different.So far, I have been running all of our ePMP APs on 20mhz channels and PTP links on 40mhz or 20mhz, depending on how much capacity they need. I haven't really seen much need to go down to 10mhz channels with ePMP.
On Mon, Jun 8, 2015 at 8:43 AM, Shayne Lebrun <slebrun@muskoka.com> wrote:
I seem to recall that with the M series, at least, a 30 mhz channel works 'better' than a 40 because the 40 is really two 20 mhz channels bonded together, where a 30 mhz channel is a 30 mhz channel.
-----Original Message-----
From: Af [mailto:af-bounces@afmug.com] On Behalf Of Rory Conaway
Sent: Saturday, June 6, 2015 8:32 PM
To: af@afmug.com
Subject: Re: [AFMUG] EPMP 10 mhz vs 20mhz
I'm not that familiar with the ePMP's yet but I can tell you some things that we saw with Ubiquiti. One is that channel width does not scale with bandwidth that that Atheros chipset. For example, 40MHz channels rarely hit their theoretical maximum due to a variety of factors, noise, lower s/n, processor limitations, etc... Second, 20MHz channels seem to be the sweet spot but even with GPS sync, you have to deal with reflections. Third, 10MHz channels have more overhead as a percentage of total capacity and don't handle a lot of users well (above 40 for example with the older 400MHz chipsets. I'm starting to deploy XW radios with the 520MHz processors but everything is 20MHz now so I don't have a comparison). We did see peaks of 32Mbps with some customers on 10MHz channels but that's non-peak times. In peak times, we were seeing 8Mbps when more users were online.
Rory
-----Original Message-----
From: Af [mailto:af-bounces@afmug.com] On Behalf Of Craig House
Sent: Saturday, June 06, 2015 5:20 PM
To: af@afmug.com
Subject: [AFMUG] EPMP 10 mhz vs 20mhz
We have deployed 6 towers to begin our new EPMP network and 4 of those towers have a full cluster of 2.4 90 degree EPMP sectors. They are configured with ACS turned off now because in several cases they all ended up on the same or very close to the same channel. I have Front back designations and non overlapping channels set up on all towers. I have tried 40 mhz 20 mhz and now 10mhz channels and while the customer stability has gotten better the more I play with settings I have kind of hit a point I dont know what else to try. I have some that the uplink quality will vary wildly from 100% to 0%. Most have gotten better since I went to a 10mhz channel. Most of the customers get 12MB -30mb down in the wireless link test but the uplinks are as bad as .17. What is the cause of this poor uplink quality? Is it interfernece? My one 5ghz AP does not have this problem but even with noise many of these customers have -50 signals and oddly enough the ones with the great signals seem to be the ones that have the poorest link tests on the up link side. I also have customes with -65 or -72 signals that get 5MB up on the same sectors? Im scratching my head a bit on what the fix is for this? Should I leave ACS on and change everything to 10mhz channels? Will a full cluster with ACS on work all on the same channel?
I'm used to FSK where you pick your channel and any channels that are adjacent will cause problems with connected SM's. So am I just applying old knowledge to a technology that it doesn't apply to?
Craig
