Basic/Mandatory Data Rates

[dogbert15]

What are the trade offs for setting the Mandatory Data rates for radios too high? 

In my own past experience have only configured mandatory rates to be somewhat leniently (ex 6mb on 2.4ghz b radio or 24mb on a 5ghz a radio). Recently came into a case supporting users at a remote site where wifi is managed by another org (but still Cisco APs/WLCs) and in tests have determine the basic mandatory rate they have configured is far higher (48mb on 5ghz) and wondering if there are  implications for serviceable (ie data carrying) cell ranges? Or anything else for that matter?

Is there a general recommendation for mandatory rates?

[marce1000]

 - The 'only' thing that can happen (but you need to look at that in the reverse-way...) that legacy-clients may no longer be able to connect.

 M.

[balaji.bandi]

I do not see any issue here, but make sure mandatory also selected.

we use 54MB also, to suport based on the requirement.

[Scott Fella]

I will just add to what everyone already mentioned.  Setting the mandatory rate high only works if all the devices can achieve that to perform the initial negotiation.  If they also have supported rates that are lower, that means that the device and ap can negotiate lower if they roam as an example.  High density, you can probably get away with it and or even making 36mbps the lowest mandatory, with 24mbps as supported.  Again.... depends on your coverage and devices.  A good example where you might get away with that is in a school where every room has an ap or multiple ap's.  Devices should be able to negotiate at the lowest mandatory rate if there is nothing else affecting that.

Don't assume that its broken unless you actually go onsite and test and speak with the end users.

[dogbert15]

I appreciate the feedback (from everyone). Maybe I should have rephrased my question to say having is the mandatory rate set too high an issue in some environments. 

From what I've seen in this particular case, the mandatory rate is set 48mbps and only other allowed rate is 54 and its not in what I would call a high density environment (office setting with several concrete walls between offices). But have seen clients with APs in same room, direct LOS, and less than 15 feet and still seeing poor thruput on 5ghz connections (as reported by clients) at this site. 

[Scott Fella · Accepted solution]

Having the wrong rates either enabled or disabled can be bad.  You will not know this unless you troubleshoot and actually see what rates these devices are connecting at, what is the channel width, channels look good or not.  Poor throughput is vague... setup an iperf3 server on wired at the local site and have a device on wireless.  See what the actual throughput is, if that shows good and internet or traffic across the wan is slower, well... you know have something to look at.