[ietf86-tech] Fwd: WAPs for Orlando

[Rick Alfvin]

See inline...

On Feb 7, 2013, at 12:33 PM, Chris Elliott <chelliot at pobox.com> wrote:

> Was in a meeting...out now...
> 
> I'm assuming the 1142s have dual radios. If not, no way.
Yes. they have two radios. The 1142s we have provide for 11a/g/n.
The 1142s have twice as much DRAM (128MB) as the 1252s (64MB)
Here's a spec sheet. http://www.cisco.com/en/US/prod/collateral/wireless/ps5678/ps10092/datasheet_c78-502793.html
> 
> The real performance difference, given both have dual radios, is that the 1252s have support for 802.11n with three antennas per radio and MIMO support, in addition to .11a,b,g support, which only gives you two antennas with diversity. This support helps all clients, not just .11n clients, including 2.4Ghz clients where we don't enable .11n--we still get benefits from the better radio for both transmission and reception. 
They provide:
• 2x3 multiple-input multiple-output (MIMO) with two spatial streams
• Maximal ratio combining (MRC)
• Legacy beamforming (hardware supports this capability; not yet enabled in software)
• 20- and 40-MHz channels
• PHY data rates up to 300 Mbps
• Packet aggregation: A-MPDU (Tx/Rx), A-MSDU (Tx/Rx)
• 802.11 dynamic frequency selection (DFS) (Bin 5)
• Cyclic shift diversity (CSD) support
> 
> While I don't have numbers, I expect the 1252s to significantly outperform the 1142s in complex environments, especially with lots of high-speed clients. We only enable the higher-speeds on the interfaces (11M and up), and we certainly have a complex environment.
> 
> The faster CPU/more memory/faster wireless cards/radios may give slight improvements as well, but I'm much less certain that it's significant.
The 1142s have twice as much DRAM (128MB) as the 1252s (64MB)
> 
> So, while I'm comfortable using the 1142s for common areas, lobbies, bars/restaurants, I would really like the 1252s for the meeting spaces, terminal room, and NOC.
> 
> Plus, we're using this installation over two meetings, so the additional installation effort and shipping costs are worth it, in my opinion.
> 
> Chris.
> 
> 
> --
> Chris Elliott
> CCIE # 2013
> 
> “You and I are mirages that perceive themselves”
> --Douglas Hofstadter
> 
> On Feb 7, 2013, at 11:46 AM, Warren Kumari <warren at kumari.net> wrote:
> 
>> 
>> On Feb 7, 2013, at 11:28 AM, Jim Martin <jim at daedelus.com> wrote:
>> 
>>> Gentlepeople,
>>>   A question from Rick. I personally am a bit leery, but I defer to our wireless experts....
>>> 
>>>   - Jim
>>> 
>>> Begin forwarded message:
>>> 
>>>> From: Rick Alfvin <ralfvin at verilan.com>
>>>> Subject: WAPs for Orlando
>>>> Date: February 7, 2013 8:14:48 AM PST
>>>> To: Jim Martin <jim at daedelus.com>
>>>> 
>>>> Hi Jim,
>>>> What would you think about using our 1142s for Orlando instead of the 1252s? IETF would save a lot of money on shipping
>> 
>> 
>> Hmmm… I think that if we do the 1142s[0] we should *also* have the 1252s available, sitting in a box incase we find some critical issue...
>> For our new kit / future meetings we could save the shipping, etc but for the first (IETF) run I think having the backup parachute might be good… (of course, not my $$$, etc)
>> 
>> W
>> [0]:  Which sounds like a fine idea to me, they seemed to work well in NANOG, better POE, etc, but not my call as I'm not the chappie supporting them…  Of course, one of Fabiha's jobs is attaching the external antennas to the 1252s, so if we don't ship them, she has less reason to attend….
>> 
>> 
>> 
>> 
>>>> and eliminate the hassle of dealing with external antennas. The 1142's have proven to be very robust for us and you'd have another performance data point when deciding what to replace the 1252's with when the gear is refreshed. 
>>>> Thanks for your consideration.
>>>> -Rick
>>>> 
>>>> Rick Alfvin
>>>> VP Business Development
>>>> 
>>>> Verilan, Inc.
>>>> 7327 SW Barnes Rd. #215
>>>> Portland, OR  97225
>>>> 
>>>> Mobile: +1 (585) 781-0952
>>>> Email: ralfvin at verilan.com
>>>> Skype: ralfvin.verilan
>>>> Website: www.verilan.com
>>> 
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>> 
>> --
>> Do not meddle in the affairs of dragons, for you are crunchy and taste good with ketchup. 
>> 
>> 
>> 
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