Number of AP N vs AG

Unanswered Question
Sep 16th, 2009


After a site survey the number of 1131's is 50% more than our vendor initially recommended, even though they had the floor plans and construction info (concrete building). I understand N AP's have better coverage/penetration. Is it easy for the vendor to re-model using N? And does N provide better coverage - thus fewer AP's?

I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 5 (3 ratings)
Leo Laohoo Thu, 09/17/2009 - 00:09

I won't go into an argument about how many APs you need to deploy for N as compared to a/b/g. This depends entirely on the model of the AP you plan to deploy and the type of antennae used.

The successor of the 1130 is the 1142. So I am guessing that you are talking about this model. If so, then it boils down to the placement of the APs.

Did the vendor perform a post-installation site survey? One thing about N is the way it "bounces" it's signal against obstructions such as wood and metal.

tsijmerrifield Thu, 09/17/2009 - 14:59

Thanks for the follow-up. We are still in planning/ordering stage and their site survey indicated +50% more AP's than initially quoted via their estimating software, as such was interested if a different A/P would reduce this #.

Leo Laohoo Thu, 09/17/2009 - 16:24

What AP was used to perform a site survey? If you plan to use the 1140, for example, then the 1140 preferably should be used during the site survey instead of the 1130.

tsijmerrifield Wed, 09/30/2009 - 12:37

Thanks for all the replies. The vendor is testing with 1130's, however we are still awaiting the final results.

rob.huffman Fri, 09/18/2009 - 05:51

Hi Jon,

Just to add a touch to the great info from our friend Leo (+5 points here Leo :) This discrepency does show the need for real "site surveys". The general thought on "N" performance is improved throughput moreso than improved coverage.

I thought that these presentations were excellent in explaining the "N" characteristics, especially the testing results! Have a look;

Cisco & Intel 802.11n Performance Results

and this excellent White Paper;

Hope this helps!


Leo Laohoo Fri, 09/18/2009 - 16:34

What the bl00dy hell am I talking `bout ... :P

I'm suspecting the vendor wasn't able to use the 1140 for site survey because the autonomous IOS for the 1140 has not yet been released by Cisco. I'm guessing an 1130 (or other model) instead was used.

There is no decent recommendation here (from me). But if I was to play it safe with my finance, I'd stick to the original number before the "50% more" figure, however, I wouldn't hold my breathe against the accuracy. Instead, prepare contingency measures and be ready to purchase and deploy more APs in a case-to-case basis or when you see fit for more.


This Discussion