topic Re: Receving from 2.4 and sending to 5 ghz in To Be Moved

Receving from 2.4 and sending to 5 ghz

jim_konng — Wed, 25 Nov 2015 16:41:57 GMT

Hi all,

Need to understand one thing. As we know that before 802.11ac MU-MIMO, it was single user communication. I just wanted to know if below scenario is applicable in real life (no specific to ruckus)

1 client associated to AP on 2.4 Ghz, another client associated to AP on 5 Ghz
On radio medium, only 1 device can sent at a time
if client 1 (2.4 ghz) is sending data, will client 2 (5 ghz) will recieve it simultaneously ?

I think in point 3, the communication should be bidirectional isnt it without any hold up since both clients are operating on different frequencies ?

Re: Receving from 2.4 and sending to 5 ghz

seanmuir — Wed, 25 Nov 2015 19:42:13 GMT

You are correct.

All you need to know is that WiFi is 50% duty cycle and the MAC layer can either be based on throughput fairness (equal amount of frames) or airtime fairness (equal amount of airtime) and this is radio dependant.

Re: Receving from 2.4 and sending to 5 ghz

john_d — Wed, 25 Nov 2015 19:49:32 GMT

A simultaneous dual-band AP can be thought of as two separate AP's operating independently: One serving 2.4GHz and one serving 5GHz. So yes, it would be possible (and has nothing to do with 802.11ac MU-MIMO) for separate clients to be either sending or receiving at the same time on 2.4GHz and 5GHz. It's merely a "convenience" that the most popular AP configuration is shipping a two-in-one dual band.

On the consumer market, you also see weirder configurations, like AP's that have two 5GHz radios and one 2.4GHz one.

But this kind of scenario isn't MU-MIMO, it's just you are saturating more of your channel spectrum with additional AP's.

Re: Receving from 2.4 and sending to 5 ghz

jim_konng — Wed, 25 Nov 2015 23:49:08 GMT

so which one does Ruckus support ? throughput fairness ? or airtime fairness ?

Re: Receving from 2.4 and sending to 5 ghz

jim_konng — Wed, 25 Nov 2015 23:49:32 GMT

so does ruckus support simultaneous dual-band AP ?

Re: Receving from 2.4 and sending to 5 ghz

john_d — Thu, 26 Nov 2015 00:19:28 GMT

Most of the Ruckus AP's do, but not all. They are clearly marked in the lineup: http://www.ruckuswireless.com/products/access-points/zoneflex-indoor

Re: Receving from 2.4 and sending to 5 ghz

seanmuir — Thu, 26 Nov 2015 09:22:47 GMT

Airtime Fairness:

https://support.ruckuswireless.com/answers/000002008

Re: Receving from 2.4 and sending to 5 ghz

michael_brado — Mon, 30 Nov 2015 18:15:23 GMT

Most Ruckus APs today are dual-band, supporting clients simultaneously on 2.4G and 5G, independent of one another.

Client load-balancing will attempt to keep even capacity between the AP radios, by monitoring client capabilities and "steering" clients to 5G.

Air Time Fairness, insures that legacy radio clients ie, 802.11b/g only, do not inhibit the throughput of 802.11n/ac capable clients,

by implementing a weighted TDM methodology.