[148465] in North American Network Operators' Group
Re: enterprise 802.11
daemon@ATHENA.MIT.EDU (Greg Ihnen)
Sun Jan 15 18:37:44 2012
From: Greg Ihnen <os10rules@gmail.com>
In-Reply-To: <8C26A4FDAE599041A13EB499117D3C286B673130@ex-mb-1.corp.atlasnetworks.us>
Date: Sun, 15 Jan 2012 19:06:26 -0430
To: Nathan Eisenberg <nathan@atlasnetworks.us>
Cc: "nanog@nanog.org" <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
Since we're already top-posting=85
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.
>=20
> 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.
>=20
> 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.
>=20
> And then, yes, Cisco is the gold standard, but it will cost you some =
gold to get it.
>=20
> Nathan
>=20
>> -----Original Message-----
>> From: Mike Lyon [mailto:mike.lyon@gmail.com]
>> Sent: Sunday, January 15, 2012 11:54 AM
>> To: Meftah Tayeb
>> Cc: nanog@nanog.org
>> Subject: Re: enterprise 802.11
>>=20
>> 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.
>>=20
>> 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.
>>=20
>> Hit me up offlist if you have any quesrions.
>>=20
>> -mike
>>=20
>> Sent from my iPhone
>>=20
>> On Jan 15, 2012, at 11:39, Meftah Tayeb <tayeb.meftah@gmail.com> =
wrote:
>>=20
>>> Ubiquity
>>> or ubikity, maybe is miss spelled
>>> Someone correct the spelling for him please thank you
>>> ----- Original Message ----- From: "Ken King" <kking@yammer-inc.com>
>>> To: <nanog@nanog.org>
>>> Sent: Sunday, January 15, 2012 9:30 PM
>>> Subject: enterprise 802.11
>>>=20
>>>=20
>>> I need to choose a wireless solution for a new office.
>>>=20
>>> up to 600 devices will connect. most devices are mac books and =
mobile
>> phones.
>>>=20
>>> we can see hundreds of access points in close proximity to our new =
office
>> space.
>>>=20
>>> what are the thoughts these days on the best enterprise =
solution/vendor?
>>>=20
>>> Thanks for your replies.
>>>=20
>>>=20
>>> Ken King
>>>=20
>>>=20
>>>=20
>>>=20
>>>=20
>>>=20
>>>=20
>>> __________ Information from ESET NOD32 Antivirus, version of virus
>> signature database 6793 (20120113) __________
>>>=20
>>> The message was checked by ESET NOD32 Antivirus.
>>>=20
>>> http://www.eset.com
>>>=20
>>>=20
>>>=20
>>>=20
>>> __________ Information from ESET NOD32 Antivirus, version of virus
>> signature database 6793 (20120113) __________
>>>=20
>>> The message was checked by ESET NOD32 Antivirus.
>>>=20
>>> http://www.eset.com
>>>=20
>>>=20
>>>=20
>>>=20
>>=20
>=20
>=20
