Does a second Mandatory Data Rate make sense ?

[ciscoprolin]

Hi guys,
we're planning to define new RF profiles on our C9800 WLCs and are wondering if it really makes sense to define 2 mandatory Data Rates ? The lower one is for beacons etc.. and the highest one is used for Multicast traffic.
Is it recommended to use just one mandatory rate and not a second one for Multicast ?
The Default Cisco RF Profiles have 2 mandatory Data Rates defined in 5 Ghz but only one in 2.4 Ghz.
What would you guys go for in 2.4 and 5 Ghz a). Office b). High Density areas c). Outdoor areas ? and what are the recommendations in 6 Ghz ?

Thanks very much

[marce1000]

 - Review this thread : https://community.cisco.com/t5/wireless/data-rates-best-practices/td-p/1794584

 M.

[Mkvts · Accepted solution]

@ciscoprolin

I always use 2 mandatory data rates (and no more then 2).

The lowest mandatory datarate is what the client devices must be able to negotiate in order to associate.
The highest mandatory rate is what multicast will prefer
It will also allow device to negotiate at a lower rate.

For example, 54 Mbps mandatory along with 24 Mbps is my best practice when I have a good density of access points.

I have used higher and lower mandatory rates in environments for better roaming experience. It really depends.

You can use tools (WiFi Explorer, Aircheck G2) which shows client devices and their advertised capabilities which includes data rates. Older devices typically need the low rates. The best way is to change it and see if the devices drop off the wireless. 

Hope this helps.

[JPavonM]

to add more to the thread @marce1000 mentioned, multicast traffic is sent to the highest mandatory rate, so better to have a high rate clsoe clients and for mcast (24 Mbps) and optionally have a lower one for clients with poor RF conditions, unless you have high density deployment and don't want clients far from the AP location to connect.

In my case I only use 1-basic-rate as I don't want clients with poor RF conditions to join and impact performance of the good ones.

[Scott Fella · Accepted solution]

Like what the others mentioned already, you can go either way, but make sure it works in your environment.  I have always gone with two mandatory rates, but which two, depends on the environment and density.  There are a few times I have gone with one and also had no issues, but you need to test and gather data to make Sure its the right choice in that environment.