how many clients will support for AP 3500 with 802.11N

[smartboy2255]

Hi All,

  I have 60 laptop users in my office. is there any AP supports 60 hosts at a time.how many clients will support for AP 3500 with 802.11N

Regards,

Ajith

[George Stefanick]

AVS,

Although you can associacte 200+ users to an AP it is not recommended. Wireless is a half duplex medium. Think of an access point as a hub. Only 1 device can talk at a time. It uses CSMA-CA.

If you had 60 folks on 1 ap your traffic would come to a craw.

Make sense?

[Leo Laohoo]

I have 60 laptop users in my office. is there any AP supports 60 hosts at a time.how many clients will support for AP 3500 with 802.11N

Another thing to consider:  What types of traffic are you trying to push.

If you are going to say, for example, emails, web browsing then I'd agree with George.  I wouldn't go in excess with 25 clients per AP.

If you are going to say voice and video, then boy, the number goes down to 3 clients per AP. 

[thomas03usmcsf]

We put a 3502 under a load test by connecting 5 iPads, 2 iPhones, and 3 laptops that were all streaming video through Netflix and Crackle and we did not experience any issues.

Sent from Cisco Technical Support iPhone App

[Leo Laohoo]

Thomas,

I'm not posting this comment to question your methodologies.  This is more for my "education".

What radio or protocol was predominantly used? 

Were there any other APs nearby or is this a "clean" room?

HD or SD video?

Thank you very much for your assistance.

[thomas03usmcsf]

Since this was a load test, it was only one ap in a clean environment with 5 clients on 2.4 and 5 clients on the 5, all streaming HD.

Sent from Cisco Technical Support iPhone App

[thomas03usmcsf]

My mistake, 7 on the 2.4 and 3 on the 5. All Apple devices were on the 2.4 and the 3 laptops were on the 5.

Sent from Cisco Technical Support iPhone App

[Leo Laohoo]

Woooooooooooooooooooooow!  Impressive.

[George Stefanick]

Keep in mind video is cached with that being said if the pipe is heavy on the wired side and the air is clean you can do double or triple that. Its when you are doing LIVE video that you will see problems.

For the record, I attached 200 cisco 7925 phones to 1 ap and did 2 voice calls with no problems. But again, not best pratice.

[thomas03usmcsf]

Thats impressive George! There are so many factors that come into play with wifi that I think it is better to fall on the safe side when it comes to ap load.

Sent from Cisco Technical Support iPhone App

[George Stefanick]

This was right before a LARGE green field deployment. I had a chance to play for a few days

[kyle woodhouse]

Hi Guys, I see quite a few posts on this topic in the support forums but this is one of the newer ones and has some intelligent people on it so I wanted an opinion.  In doing some reading and talking to people the general consensus is that 802.11n DOES increase the number of users per AP but there is no talk of how much.

This link seems to say "8x more users/clients." 

http://www.cisco.com/en/US/solutions/collateral/ns340/ns394/ns348/ns767/white_paper_c11-513840.html

I think that may be more marketing than real life because the old number was no more than 24 clients with 802.11g and that would mean 192 clients per 802.11n access point which seems a bit much. 

I realized the downfalls of wireless so please spare the typical responses about half duplex, shared medium, RF interference, what speed does each user need, type of traffic, site survey, etc etc .  All I really want is a general answer like the one from this link:

http://www.cisco.com/en/US/products/hw/wireless/ps430/products_qanda_item09186a008009483e.shtml

Q. How many clients can associate to the AP?

A. The AP has the physical capacity to handle 2048 MAC addresses, but, because the AP is a shared medium and acts as a wireless hub, the performance of each user decreases as the number of users increases on an individual AP. Ideally, not more than 24 clients can associate with the AP because the throughput of the AP is reduced with each client that associates to the AP.

Now this link and its answer were made several years ago and dealt with 802.11g.  The link is in the 1200 series access points section and arguably doesn’t encompass 802.11n. 

Now my question.  Can i make the below guestimate with the understanding of all challenges that come with wireless?

Shared Medium     # of users per radio

802.11a               15

802.11b               20-25

802.11g               20-25

802.11n               ?? Suggestion below

802.11n (1042 2x2:2 Mimo) 30 clients per radio

802.11n (1142 2x3:2 Mimo) 40 clients per radio

802.11n (1262 2x3:2 Mimo) 40 clients per radio

802.11n (3502 2x3:2 Mimo) 40 clients per radio

802.11n (3602 4x4:3 Mimo) 50 clients per radio

I realized the overhead with additional clients but isnt 802.11n supposed to deal with this much better?  There are more input and output antenna options with increased spatial streams and those units should deal with interfearance and increased users over the old units.  Are my above guesses ok for light use scenario?.

Thoughts?

[Scott Fella]

Kyle,

What you need to look at is the over subscription on the gigabit port. 802.11N does give you more throughout on the wireless, but your bottleneck is still your gigabit port. I still think 25 is a good average per radio, but as everyone will tell you, it depends on your applications. How much bandwidth do you want to make sure each client will have. Then you can do the math on how many clients per ap will work for you.

Sent from Cisco Technical Support iPad App

[kyle woodhouse]

Hi Scott.  Thanks for the quick reply.  About the gigabit port, the old reccomendation of 25 was for 802.11g access points and all of them had only 10/100 ports.  The only access points that have gigabit ports on them are the new 802.11n units.   

Doesnt that just further support a possible increase in clients per radio?  Am i way off here?

[Scott Fella]

Yes, that's why I mentioned 25 per radio not 25 per AP. That kind of gives you an average of maybe 50. I had an install where the requirement was for video transfers. The max client on either radio was 5. So it depends on your requirements.

Sent from Cisco Technical Support iPad App