[148485] in North American Network Operators' Group

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Re: enterprise 802.11

daemon@ATHENA.MIT.EDU (Greg Ihnen)
Mon Jan 16 11:14:11 2012

From: Greg Ihnen <os10rules@gmail.com>
In-Reply-To: <-7665060707062421807@unknownmsgid>
Date: Sun, 15 Jan 2012 19:28:19 -0430
To: Mike Lyon <mike.lyon@gmail.com>
Cc: "nanog@nanog.org" <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org

Very cool. Because all the individual APs are in one enclosure and I =
assume are under control of one central controller, I bet they're =
sync'ing all the AP's transmitters to transmit and listen at the same =
time so the APs don't interfere with each other. Cisco does that in =
their Canopy line with GPS sync.

Greg

On Jan 15, 2012, at 7:12 PM, Mike Lyon wrote:

> Another one which looks promising for high-density locations is Xirrus
> (www.xirrus.com)
>=20
> Haven't ever used them though.
>=20
> -mike
>=20
> Sent from my iPhone
>=20
> On Jan 15, 2012, at 15:36, Greg Ihnen <os10rules@gmail.com> wrote:
>=20
>> Since we're already top-posting=85
>>=20
>> 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.
>>=20
>> 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.
>>=20
>> 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.
>>=20
>> 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.
>>=20
>> Greg
>>=20
>> On Jan 15, 2012, at 4:22 PM, Nathan Eisenberg wrote:
>>=20
>>> 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
>>=20



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