Wireless Access

Hello

Okay i was wondering  about these vs and i really want to clarify this.

 

It supposed that its recommended for example for an AP 105 to be no more than 25 users per band...

As we know the wireless is a shared medium  on 2.4ghz a 105 will go up to 150Mbps and on 5Ghz up to 300Mbps(that knowing that we will just use 20mhz channel on 2.4ghz)

So the AP just can speak with one client at once per band it means that if we got 30 users in a band it will have to go and one by one attend each user...

 

So if we got 25 clients in each band for an AP 105 and we got airtime fairness on it should take the same time to attend all the 50 clients  than a 135 or 115?

I know the 135 and 115 got better CPU  though

 

Even if its a 135 if we got 40 clients on one band it will work slower as it has to attend more clients as it does not matter how much CPU it has, it give it an amount of time to each client with airtime fairness... 

 

At the end my question summery in how many clients are recommended on 2.4ghz and on 5ghz  on AP 105, on AP 135 and on AP 115? also on AP 175P?

 

I also will like to be more clear with this and if it possible someone to explain me better? :)

 

Thanks

Carlos

 

 

#AP135

Great thoughts Carlos...

 

The way I typically look at it Carlos is to look at a few parameters, namely:

 

1.  the total bps of the given radio first.

In the case of AP-105 you have 300Mbps max, AP-115 you have 450Mbps max, the AP-135 450 Mbps.   So right away, the AP115 and AP135 have advantages of 50% over the AP-105.  That is... as long as... your clients are 3 stream 802.11n clients.  If they aren't then they don't 'see' the 50% throughput capability improvement and you have apples:apples from a throughput standpoint.

 

2.   the vintage of the access point.  

We have hundreds of people in R&D every hour of every working day.  Those add up in my opinion.   A simple look at the birthdays will tell you the AP-105 is 2009 vintage, the AP-135 last year, and the AP-115 this year as examples.

 

3.  the memory and cpu design

In the case of the AP-135, it has the largest allocation of 'resources' of the APs I am discussing in this reply.   Thus, it stands to reason it can be loaded to the highest levels regardless of the capabilities of the clients attaching.    

 

Said another way:  

 

When I want maximum density; go AP-135 :)    (Or better yet AP-225 !!) 

 

When I want 3 stream 450Mbps 802.11n, medium density, go AP-115

 

Everything else, I continue to go AP-105

 

JF

 

PS - there is no exact number on client count, as that is but one parameter to consider.  Think of 50 iPhones sitting in pockets, vs. 10 iPads downloading the recent iOS7 update.   Are the 50 iphones more or less of a loading on the network than the 10iPads?  Pretty easy to see there that we need to take into account utilization.        

 

PPS - my record on an access point?  220 clients from a K-12 school.   Routinely I see APs pushing 50,100,150,200 clients.   They all work, however everyone 'waits their turn' as you point out.  Far from ideal.  The solution?  More radios, and our client match in those high usage areas.

 

 

Great post!

One last question regarding what you said of 50 iphones on the pocket vs 10 ipads downloding the lastest IOS

 

If i got 50 iphones attached to the AP not downloading anything it will still consume memory and cpu? if i look it this way well it doesnt matter  if the client is using the BW or not(i suppose that if the clietn does not have anything to trasnmit then it pass to the next client? im supposing as i dont know the algorithm of the air time fairness of Aruba)it will consume memory...

So this mean that in higher density an AP 135 would do better, because not all the clients will have something to transmit... than the 105... not because of the BW they can use it is more of cpu and memory allocation issue.

 

Im right or i totallly missed your point here?

 

I really want to understand this because people just want to buy the cheaper AP...  even if you recomend them others,  there is even a k12 using AP 93s and its a HD enviroment.. but for some reason is not doing bad(but they could do it a way better with ap135)... let say aruba is just too good :P But then i got another K12 which we recommend at first AP 135 for their HD enviroment... they bough 105... but then the IT manager bough one 135 he tested it and of course he saw the different! now he just buy AP 135s... and next year hope he dicide for AP 225 whcih i recommended them.

 

I really need to be really clear with this to  explain it to the client  so he can undrerstand why we are recommending it, its not about selling it something  more expensive which they see it that way.

 

 

PD

I was asking you about the numbers because the clients always ask me but tell me a recommended number! whcih my AP 105 can handle? and how many devices will handle correctly an AP 115 or AP 135?? whats the difference they ask me!

 

Thanks

Carlos

 

Thanks Carlos, it's always great to dialogue with you.

 

I know the situation you speak of all too well;   "How many clients?"  "How fast does it go?"  "Are you faster than Vendor X?"

 

... That depends ...   <smirk, deep breath, and collect thoughts>

 

I think of the faster CPU and more memory footprint as assets to enable the AP to do more 'transactions' per second, sometimes those transactions are Associations, sometimes authentications, sometimes downstream data transfer to clients, sometimes data transfer from clients, sometimes IDS, sometimes IPS, sometimes RF scanning, sometimes spectrum analysis.  

 

The AP-11x is quite likely the 'sweet spot' to recommend if you 'sell' it (errr I mean explain it ;)) as the best of 'all worlds'.   Benefiting from the 50% channel throughput advantages that the AP-135 design has over the AP-105, and enabling the end-user to support higher densities of clients than the AP-105 does, with a design that is 4 years newer.  The price premium is $200 per AP less discount, so perhaps $150 per AP.   Money well spent to buy something with '4' years more lifespan is how I pitch it when needed. 

 

JF

 

yeah it always depend... thats always my line :P

 

Anyways thanks for your reply its more clear now to me!

 

Thanks a lot for your time!!!!

 

Cheers

Carlos

Anytime Carlos.

 

Chat soon...

JF

I`d like to quickly chime in. :)

AP-135 definitely has a better radio and RF presence than the 105 but what about the 115...???

The AP-11x is quite likely the 'sweet spot' to recommend if you 'sell' it (errr I mean explain it ) as the best of 'all worlds'.   

 

The difference in AP-115 to AP-135 is in the area of client densities within the design.  That means the allocation of CPU and memory footprint (resources) in the AP-135 is geared to higher (more) density than AP-115.   

 

"Better Radio" and "RF Presence" I think are synonyms for saying 'better coverage', and usually (i find) the discussions today aren't so much about coverage they are are about accomodating the expected density of a given environment. 

 

e.g. Capacity requirements 'trump' coverage requirements, as once you accomodate capacity you automagically answer-the-mail on coverage in the process.

 

JF

Definitely understand the need for capacity. In my particular situation I do not think capacity is a problem but due to the layout and placement of APs (without moving them all, which customer will not do), I need to replace 93s with something that will provide better coverage in a hotel.

 

I was thinking 105 but if the 115 can provide more coverage than a 105, than it is a no brainer.

 

It is a terrible design that unfortunately I need to find a way with the current placement of APs to improve signal strength.

 

Are the AP-93s at full power already ?

yes they are unfortunately.

Thoughts? I've been looking at this a little further and client goodput is ok. Channel utilization is anywhere between 2-12% but this could be because of usage (client aware is on).
Thinking of disabling b basic rates from what I see from airwaves reporting not much b going on or at all.

Still waiting on pricing for 115s but definitely thinking moving the aps out of the drop ceiling and mounting them on the the t-bars along with changing to 105 or 115s would greatly benefit the customer

FYI: a colleague did a quick test in our underground parking garage and got a substantial improvement in coverage going from AP-105 to AP-115. He only tested 2.4GHz though. :smileymad:

 

And yes, there are plenty of situations where coverage is far more important than density.

 

Koenv,

 

Tell us more on the results and the test conditions used when you can... agreed on the 2.4 GHz only piece ;(

 

I'll be curious as to what kind of tests you guys typically do when comparing this kind of stuff.   

 

JF

 

 

BTW, the pricing on the AP-115 is $895 USD  aka.  +$200 USD LIST over the AP-105  and -$200 USD LIST under the AP-135.

 

Aha, right in the middle.  I think someone above described it as a 'sweet spot'.  Oh yeah, i remember who ;-)

 

JF

was you!

Question: What amount of users can each AP support?
I know this depends on network and type of clients but are there any numbers?

105: 20-25 users per radio??
115: 30-40 users per radio??
135: 40-50 users per radio??

For example..

This thread has fizzled out a bit but I'm currently in the same predicament here as well

 

I currently have AP-105's and for reasons I don't want to get into here, we are looking at upgrading to AP-115 or 135 Maybe?

 

We are a school with 1 to 1 ipad program with an AP 105  covering in each classroom

 

We have approx 25 + iPads/devices in each classroom...

 

Would the AP 115 be sufficient?  from my reading the 115 is for better "coverage" and the 135 for better "density"

 

I don't think we'll go over 30 devices on one classroom at a time.

 

Your prompt response is greatly appreciated.

srfrdrew, the 115 will certainly handle 30 iPads on a single AP, esp if you are doing it now with the 105s. The 115s have more CPU and better radios.

Access point information is very fragmented and that's why I made an "Aruba access point portoflio overview", based on the datasheets and practical use. An one-page file which gives you an instant non-cluttered overview of the current Aruba portfolio (Indoor and internal antenna's only).

 

PDF: goo.gl/sl34HV

 

Feedback appreciated