Since we're already top-posting…

I've heard a lot of talk on the WISPA (wireless ISP) forum that 802.11g/n 
starts to fall apart with more than 30 clients associated if they're all 
reasonably active. I believe this is a limitation of 802.11g/n's media access 
control (MAC) mechanism, regardless of who's brand is on the box. This is most 
important if you're doing VoIP or anything else where latency and jitter is an 
issue.

To get around that limitation, folks are using proprietary protocols with 
"polling" media access control. Ubiquiti calls theirs AirMax. Cisco uses 
something different in the "Canopy" line. But of course then you've gone to 
something proprietary and only their gear can connect. So it's meant more for 
back-hauls and distribution networks, not for end users unless they use a 
proprietary CPE.

Since you need consumer gear to be able to connect, you need to stick with 
802.11g/n. You should limit to 30 clients per AP. You should stagger your 
2.4GHZ APs on channels 1, 6 and 11, and turn the TX power down and have them 
spaced close enough that no more than 30 will end up connecting to a single AP. 
5.8GHz APs would be better, and you'll want to stagger their channels too and 
turn the TX power down so each one has a small footprint to only serve those 
clients that are nearby.

Stay away from "mesh" solutions and WDS where one AP repeats another, that 
kills throughput because it hogs airtime. You'll want to feed all the APs with 
Ethernet.

Greg

On Jan 15, 2012, at 4:22 PM, Nathan Eisenberg wrote:

> Ubiquiti's Unifi products are decent, and have *MUCH* improved since their 
> original release (amazing what you can do with better code!).  In the 
> original release, you had to have a management server running on the same L2 
> network as the Aps - they've moved the management to a L3 model so you can 
> put the controller elsewhere.  The big PITA with their system is that any 
> change requires 'reprovisioning' the APs, which means rebooting all of them 
> in sequence.  They've added VLANs, multiple SSID's/AP, wireless 
> backhaul/chaining, guest portalling, and limiters to balance the # of clients 
> / AP.
> 
> In a noisy environment, I've found that they top out at around 30 devices / 
> AP for good performance, and 50 devices / AP for 'working/not working'.  In a 
> clean environment, I've seen decent performance with 70 - 100 devices / AP.  
> Of course, if one bad client comes along (with a card that doesn't backoff 
> its TX power, etc), it can wreak havoc with higher densities.  You really 
> can't argue with Unifi's price.
> 
> If you move up the price scale, Meraki seems to be a good midrange solution, 
> and they have some really sweet reporting functionality.  They're more 
> expensive, though.
> 
> And then, yes, Cisco is the gold standard, but it will cost you some gold to 
> get it.
> 
> Nathan
> 
>> -----Original Message-----
>> From: Mike Lyon [mailto:mike.l...@gmail.com]
>> Sent: Sunday, January 15, 2012 11:54 AM
>> To: Meftah Tayeb
>> Cc: nanog@nanog.org
>> Subject: Re: enterprise 802.11
>> 
>> Ubiquity (www.ubnt.com) has their Unifi line of products. It's still pretty 
>> new
>> in the marketspace and this, working out the bugs. I use their other products
>> exclusively for outdoor wireless.
>> 
>> However, in the offices ive done, ive used Cisco's WLC 4402 controller which
>> supports 12 access points. They have controllers which support more APs as
>> well.
>> 
>> Hit me up offlist if you have any quesrions.
>> 
>> -mike
>> 
>> Sent from my iPhone
>> 
>> On Jan 15, 2012, at 11:39, Meftah Tayeb <tayeb.mef...@gmail.com> wrote:
>> 
>>> Ubiquity
>>> or ubikity, maybe is miss spelled
>>> Someone correct the spelling for him please thank you
>>> ----- Original Message ----- From: "Ken King" <kk...@yammer-inc.com>
>>> To: <nanog@nanog.org>
>>> Sent: Sunday, January 15, 2012 9:30 PM
>>> Subject: enterprise 802.11
>>> 
>>> 
>>> I need to choose a wireless solution for a new office.
>>> 
>>> up to 600 devices will connect.  most devices are mac books and mobile
>> phones.
>>> 
>>> we can see hundreds of access points in close proximity to our new office
>> space.
>>> 
>>> what are the thoughts these days on the best enterprise solution/vendor?
>>> 
>>> Thanks for your replies.
>>> 
>>> 
>>> Ken King
>>> 
>>> 
>>> 
>>> 
>>> 
>>> 
>>> 
>>> __________ Information from ESET NOD32 Antivirus, version of virus
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>>> The message was checked by ESET NOD32 Antivirus.
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>>> http://www.eset.com
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>>> 
>>> 
>>> __________ Information from ESET NOD32 Antivirus, version of virus
>> signature database 6793 (20120113) __________
>>> 
>>> The message was checked by ESET NOD32 Antivirus.
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>>> 
>> 
> 
> 


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