WiFi 6E Migration Recommendations

[packet2020]

Hi All

I am currently working on a project to replace an existing AireOS based wireless network with a new Cisco 9800 WLC with 9100 series access points. This will be a gradual migration by installing the new 9800 WLC in parallel to the existing and then rolling out the 9100 access points on a building by building basis. The project also includes the enablement of WiFi 6E with 6GHz and WPA3 on the main corporate SSID. Is it recommend to introduce WiFi 6E and WPA3 (using transition mode) on the corporate SSID and new access points as they are rolled out which will operate in parallel to the existing access points for a short period, or is it recommend to complete the installation of the 9100 APs first and then introduce WPA3 and 6GHz? I'm trying to determine if running 6GHz/WPA3 in paralell to the existing wireless network will introduce roaming issues etc.

[Leo Laohoo]

What is the total quantity of APs? 

What is the exact model of 9800?

What is the exact model of "9100"?

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@packet2020 wrote:
I'm trying to determine if running 6GHz/WPA3 in paralell to the existing wireless network will introduce roaming issues etc.

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We have transition SSID for 6Ghz and with only a very small amount of wireless clients capable, we have not received any noise about "roaming".

[packet2020]

What is the total quantity of APs? = ~2000

What is the exact model of 9800? = CW9800H1

What is the exact model of "9100"? = CW9166I

In your enviroment did you have WiFi 6E access points operating in parallel to existing legacy APs? Typically we would migrate a coverage area at a time to prevent issues with legacy and lastest gen APs from operating within the same space, however this is not always acheivable in practise so we will have some of the 9166I APs broadcasting SSID "corp" with 5/6GHz WPA2/WPA3 transition mode and some legacy APs broadcasting "corp" with 5GHz WPA2 within the same space. I appreciate that roaming across 6GHz will not be feasable until all APs have been swapped out with 9166Is, but I wanted to check if there are any other significant gotchas with this approach.

[Leo Laohoo]

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@packet2020 wrote:
What is the exact model of "9100"? = CW9166I

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Do not be in a hurry to purchase the 9166 because the 917x line-up is not yet complete.  Two more models, the ultra premium 9179 and the sub-sub-sub 9174, will be announced during Cisco Live San Diego 2025.  Talk to the Cisco Account Manager because they've been promising "price matching" with the existing 9136/916x line-up.  

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@packet2020 wrote:
In your enviroment did you have WiFi 6E access points operating in parallel to existing legacy APs?

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We do not "mix" different AP models/generation in every sites (and we have >400 sites).  

Is/Are the site(s) a 24x7-uptime environment? 

[marce1000]

            -  FYI : https://blogs.cisco.com/networking/migrating-to-6ghz

  M.

[Rich R]

And to add to the link @marce1000 provided above - you should also have a good read through https://www.cisco.com/c/en/us/td/docs/wireless/controller/9800/technical-reference/wpa3-dg.html which has been updated more recently.

I'll add my bit about our experience with transition mode and WPA3 - we tried it and abandoned it:
- Windows treats the transition mode SSID like a "new network" and shows the SSID with a number appended, so if the SSID was called "MY-SSID" then Windows shows it as "MY-SSID 2" - confusing for users and other possible problems.
- Windows devices with old Intel drivers were not able to connect to the SSID at all.

So now we stick with an Open/WPA2 SSID on 2.4 and 5 GHz with a new WPA3 SSID on 6 GHz.  One day when everything supports WPA3 we'll move them all to WPA3 on a single SSID.

I do not have any testing to prove it either way but mixing WPA2 and WPA3 on the same SSID in the same location sounds like a recipe for pain - I would not recommend that myself.  Remember any client roaming between WPA2 and WPA3 must complete a full re-authentication - it is never seamless.

There are a few Cisco Live presentations which also discuss these issues so take a look at those too - both in the context of WiFi 6E and WiFi 7.